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Vertebrate Endoderm Development and Organ Formation
Vertebrate Endoderm Development and Organ Formation
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2861293/?tool=pubmed
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2861293/?tool=pubmed




 
1: Duboc V, Lapraz F, Saudemont A, Bessodes N, Mekpoh F, Haillot E, Quirin M,
1. Development. 2010 Jan;137(2):223-35.
Lepage T. Nodal and BMP2/4 pattern the mesoderm and endoderm during development
 
of the sea urchin embryo. Development. 2010 Jan;137(2):223-35. PubMed PMID:
Nodal and BMP2/4 pattern the mesoderm and endoderm during development of the sea
20040489.
urchin embryo.
 
Duboc V, Lapraz F, Saudemont A, Bessodes N, Mekpoh F, Haillot E, Quirin M, Lepage
T.
 
UPMC Univ Paris 06-CNRS, UMR 7009 Biologie du Développement Observatoire
Océanologique, 06230 Villefranche-sur-mer, France.
 
Nodal factors play fundamental roles in induction and patterning of the mesoderm
and endoderm in vertebrates, but whether this reflects an ancient role or one
that evolved recently in vertebrates is not known. Here, we report that in
addition to its primary role in patterning the ectoderm, sea urchin Nodal is
crucial for patterning of the endoderm and skeletogenic mesoderm through the
regulation of the expression of key transcription factors and signalling
molecules, including BMP2/4 and FGFA. In addition, we uncovered an essential role
for Nodal and BMP2/4 in the formation and patterning of the non-skeletogenic
mesoderm. By comparing the effects of misexpressing Nodal or an activated Nodal
receptor in clones of cells, we provide evidence that Nodal acts over a long
range in the endomesoderm and that its effects on the blastocoelar cell
precursors are likely to be direct. The activity of Nodal and BMP2/4 are
antagonistic, and although bmp2/4 is transcribed in the ventral ectoderm
downstream of Nodal, the BMP2/4 ligand is translocated to the dorsal side, where
it activates signalling in the dorsal primary mesenchyme cells, the dorsal
endoderm and in pigment cell precursors. Therefore, correct patterning of the
endomesoderm depends on a balance between ventralising Nodal signals and
dorsalising BMP2/4 signals. These experiments confirm that Nodal is a key
regulator of dorsal-ventral polarity in the sea urchin and support the idea that
the ventral ectoderm, like the Spemann organiser in vertebrates, is an organising
centre that is required for patterning all three germ layers of the embryo.
 
PMID: 20040489 [PubMed - indexed for MEDLINE]
 
 
2. Dev Biol. 2010 Jan 1;337(1):63-73. Epub 2009 Oct 20.
 
Gata4 directs development of cardiac-inducing endoderm from ES cells.
 
Holtzinger A, Rosenfeld GE, Evans T.
 
Department of Surgery, Weill Cornell Medical School, New York, NY 10021, USA.
 
The transcription factor Gata4 is essential for normal heart morphogenesis and
regulates the survival, growth, and proliferation of cardiomyocytes. We tested if
Gata4 can specify cardiomyocyte fate from an uncommitted stem or progenitor cell
population, by developing a system for conditional expression of Gata4 in
embryonic stem cells. We find that in embryoid body cultures containing even a
low ratio of these cells, expression of Gata4 is sufficient to enhance
significantly the generation of cardiomyocytes, via a non-cell-autonomous
mechanism. The Gata4-expressing cells do not generate cardiac or other mesoderm
derivatives. Rather, Gata4 expression directs the development of two types of
Sox17+ endoderm. This includes an epCam+Dpp4+ subtype of visceral endoderm. In
addition, Gata4 generates similar amounts of epCam+Dpp4- definitive endoderm
enriched for Cxcr4, FoxA2, FoxA3, Dlx5 and other characteristic transcripts. Both
types of endoderm express cardiac-inducing factors, including WNT antagonists
Dkk1 and Sfrp5, although the visceral endoderm subtype has much higher
cardiac-inducing activity correlating with relatively enhanced levels of
transcripts encoding BMPs. The Gata4-expressing cells eventually express
differentiation markers showing commitment to liver development, even under
conditions that normally support mesoderm development. The results suggest that
Gata4 is capable of specifying endoderm fates that facilitate, with temporal and
spatial specificity, the generation of cardiomyocyte progenitors from associated
mesoderm.
 
PMCID: PMC2799892 [Available on 2011/1/1]
PMID: 19850025 [PubMed - indexed for MEDLINE]
 
 
3. Annu Rev Cell Dev Biol. 2009;25:221-51.
 
Vertebrate endoderm development and organ formation.
 
Zorn AM, Wells JM.
 
Division of Developmental Biology, Cincinnati Children's Research Foundation and
Department of Pediatrics, College of Medicine, University of Cincinnati,
Cincinnati, Ohio 45229, USA. aaron.zorn@cchmc.org
 
The endoderm germ layer contributes to the respiratory and gastrointestinal
tracts and to all of their associated organs. Over the past decade, studies in
vertebrate model organisms, including frog, fish, chick, and mouse, have greatly
enhanced our understanding of the molecular basis of endoderm organ development.
We review this progress with a focus on early stages of endoderm organogenesis
including endoderm formation, gut tube morphogenesis and patterning, and organ
specification. Lastly, we discuss how developmental mechanisms that regulate
endoderm organogenesis are used to direct differentiation of embryonic stem cells
into specific adult cell types, which function to alleviate disease symptoms in
animal models.
 
PMCID: PMC2861293
PMID: 19575677 [PubMed - indexed for MEDLINE]
 
 
4. Dev Dyn. 2009 Mar;238(3):514-23.
 
C-Fos elimination compensates for disabled-2 requirement in mouse extraembryonic
endoderm development.
 
Yang DH, Smith ER, Cai KQ, Xu XX.
 
Ovarian Cancer Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA.
 
Disabled-2 (Dab2) is expressed in primitive endoderm cells as they are
differentiating from the inner cell mass and dab2 deficiency in mice results in
lethality at E5.5-E6.5 due to the disorganization of the endoderm layers. Here we
show that Dab2 suppresses c-Fos expression in endoderm cells. A morphological
normal primitive endoderm layer was observed in putative E5.5 dab2 (-/-):c-fos
(-/-) embryos, indicating that the primitive endoderm defect due to the loss of
Dab2 is rescued by deletion of the c-fos gene. The lethality of the double
knockout embryos was delayed until E9.5-E10.5 and the defective embryos failed to
undergo organogenesis. We conclude that Dab2 plays a role in epithelial
organization by suppression of c-Fos expression and suggest that unsuppressed
c-Fos can lead to disruption of primitive endoderm epithelial organization, yet
an additional dab2 function is required for later organogenesis. (c) 2009
Wiley-Liss, Inc.
 
PMCID: PMC2743073
PMID: 19191218 [PubMed - indexed for MEDLINE]
 
 
5. Cytotechnology. 2008 Jun;57(2):151-9. Epub 2008 Feb 12.
 
Cephalic hedgehog expression is regulated directly by Sox17 in endoderm
development of Xenopus laevis.
 
Yagi Y, Ito Y, Kuhara S, Tashiro K.
 
Graduate School of Systems Life Sciences, Kyushu University, Hakozaki,
Higashi-ku, Fukuoka, 812-8581, Japan.
 
In early development of animals, hedgehog (Hh) genes function as morphogen in the
axis determination and the organ formation. In Xenopus, three hedgehog genes,
sonic (shh), banded (bhh), and cephalic (chh), were identified and might organize
various tissues and organs in embryogenesis. Here, we report the spatial and
temporal regulation of Xchh which is expressed in endoderm cells differentiating
to digestive organs. Xchh expression in endoderm was inhibited by ectopic
expression of the dominant-negative activin receptor, tAR. Moreover, a maternally
inherited transcription factor VegT and its downstream regulators activated Xchh
expression. These indicates that Xchh is regulated by the factor involved in the
cascade originated from VegT via activin/nodal signals. Using the
Sox17alpha-VP16-GR construct, we showed that Xchh expression might be induced
directly by transcription factor Sox17.
 
PMCID: PMC2553669
PMID: 19003160 [PubMed - in process]
 
 
6. Dev Growth Differ. 2008 Sep;50(7):615-21.
 
Bone morphogenetic protein 4 signaling regulates development of the anterior
visceral endoderm in the mouse embryo.
 
Soares ML, Torres-Padilla ME, Zernicka-Goetz M.
 
The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge,
Tennis Court Road, Cambridge CB2 1QR, UK.
 
The extraembryonic ectoderm (ExE) of the mouse conceptus is known to play a role
in embryo patterning by signaling to the underlying epiblast and surrounding
visceral endoderm. Bmp4 is one of the key ExE signaling molecules and has been
recently implicated to participate in regulating development and migration of the
anterior visceral endoderm (AVE). However, it remains unclear when exactly BMP4
signaling starts to regulate AVE positioning. To examine this, we have chosen to
affect BMP4 function at two different time points, at embryonic day 5.25 (E5.25),
thus before AVE migration, and E5.75, just after AVE migration. To this end, an
RNAi technique was used, which consisted of the injection of Bmp4 dsRNA into the
proamniotic cavity of the egg cylinder followed by its targeted electroporation
into the ExE. This resulted in specific knockdown of Bmp4. It was found that Bmp4
RNAi at E5.25, but not at E5.75, led to an abnormal pattern of expression of the
AVE marker Cerberus-like. Thus, BMP4 signaling appears to affect the expression
of Cer1 at a specific time window. This RNAi approach provides a convenient means
to study spatial and temporal function of genes shortly after embryo
implantation.
 
PMID: 18657169 [PubMed - indexed for MEDLINE]
 
 
7. Dev Biol. 2008 Jun 1;318(1):52-64. Epub 2008 Mar 20.
 
Endoderm-derived Sonic hedgehog and mesoderm Hand2 expression are required for
enteric nervous system development in zebrafish.
 
Reichenbach B, Delalande JM, Kolmogorova E, Prier A, Nguyen T, Smith CM,
Holzschuh J, Shepherd IT.
 
Department of Developmental Biology, University of Freiburg, Biology I,
Hauptstrasse 1, 79104 Freiburg, Germany.
 
The zebrafish enteric nervous system (ENS), like those of all other vertebrate
species, is principally derived from the vagal neural crest cells (NCC). The
developmental controls that govern the migration, proliferation and patterning of
the ENS precursors are not well understood. We have investigated the roles of
endoderm and Sonic hedgehog (SHH) in the development of the ENS. We show that
endoderm is required for the migration of ENS NCC from the vagal region to the
anterior end of the intestine. We show that the expression of shh and its
receptor ptc-1 correlate with the development of the ENS and demonstrate that
hedgehog (HH) signaling is required in two phases, a pre-enteric and an enteric
phase, for normal ENS development. We show that HH signaling regulates the
proliferation of vagal NCC and ENS precursors in vivo. We also show the zebrafish
hand2 is required for the normal development of the intestinal smooth muscle and
the ENS. Furthermore we show that endoderm and HH signaling, but not hand2,
regulate gdnf expression in the intestine, highlighting a central role of
endoderm and SHH in patterning the intestine and the ENS.
 
PMCID: PMC2435286
PMID: 18436202 [PubMed - indexed for MEDLINE]
 
 
8. Dev Biol. 2008 May 15;317(2):467-79. Epub 2008 Mar 4.
 
Multiple roles for Med12 in vertebrate endoderm development.
 
Shin CH, Chung WS, Hong SK, Ober EA, Verkade H, Field HA, Huisken J, Stainier DY.
 
Department of Biochemistry and Biophysics, Liver Center, University of
California, San Francisco, CA 94158, USA. chong.shin@ucsf.edu
 
In zebrafish, the endoderm originates at the blastula stage from the most
marginal blastomeres. Through a series of complex morphogenetic movements and
differentiation events, the endodermal germ layer gives rise to the epithelial
lining of the digestive tract as well as its associated organs such as the liver,
pancreas, and swim bladder. How endodermal cells differentiate into distinct cell
types such as hepatocytes or endocrine and exocrine pancreatic cells remains a
major question. In a forward genetic screen for genes regulating endodermal organ
development, we identified mutations at the shiri locus that cause defects in the
development of a number of endodermal organs including the liver and pancreas.
Detailed phenotypic analyses indicate that these defects are partially due to a
reduction in endodermal expression of the hairy/enhancer of split-related gene,
her5, at mid to late gastrulation stages. Using the Tg(0.7her5:EGFP)(ne2067)
line, we show that her5 is expressed in the endodermal precursors that populate
the pharyngeal region as well as the organ-forming region. We also find that
knocking down her5 recapitulates some of the endodermal phenotypes of shiri
mutants, further revealing the role of her5 in endoderm development. Positional
cloning reveals that shiri encodes Med12, a regulatory subunit of the
transcriptional Mediator complex recently associated with two human syndromes.
Additional studies indicate that Med12 modulates the ability of Casanova/Sox32 to
induce sox17 expression. Thus, detailed phenotypic analyses of embryos defective
in a component of the Mediator complex have revealed new insights into discrete
aspects of vertebrate endoderm development, and provide possible explanations for
the craniofacial and digestive system defects observed in humans with mutations
in MED12.
 
PMCID: PMC2435012
PMID: 18394596 [PubMed - indexed for MEDLINE]
 
 
9. Mech Dev. 2008 May-Jun;125(5-6):377-95. Epub 2008 Feb 20.
 
Foregut endoderm is specified early in avian development through signal(s)
emanating from Hensen's node or its derivatives.
 
Matsushita S, Urase K, Komatsu A, Scotting PJ, Kuroiwa A, Yasugi S.
 
Department of Biology, School of Medicine, Tokyo Women's Medical University, 8-1
Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan. matsus@research.twmu.ac.jp
 
In this study, the initial specification of foregut endoderm in the chick embryo
was analyzed. A fate map constructed for the area pellucida endoderm at
definitive streak-stage showed centrally-located presumptive cells of
foregut-derived organs around Hensen's node. Intracoelomic cultivation of the
area pellucida endoderm at this stage combined with somatic mesoderm resulted in
the differentiation predominantly into intestinal epithelium, suggesting that
this endoderm may not yet be regionally specified. In vitro cultivation of this
endoderm for 1-1.5 day combined with Hensen's node or its derivatives but not
with other embryonic structures/tissues elicited endodermal expression of cSox2
but not of cHoxb9, which is characteristic of specified foregut endoderm. When
the anteriormost or posteriormost part of the area pellucida endoderm at this
stage, whose fate is extraembryonic, was combined with Hensen's node or its
derivatives for 1 day, then enwrapped with somatic mesoderm and cultivated for a
long period intracoelomically, differentiation of various foregut organ epithelia
was observed. Such epithelia never appeared in the endoderm associated with other
embryonic structures/tissues and cultured similarly. Thus, Hensen's node and its
derivatives that lie centrally in the presumptive endodermal area of the foregut
are likely to play an important role in the initial specification of the foregut.
Chordin-expressing COS cells or noggin-producing CHO cells transplanted into the
anteriormost area pellucida of the definitve streak-stage embryo could induce
endodermal expression of cSox2 but not of cHoxb9, suggesting that chordin and
noggin that emanate from Hensen's node and its derivatives, may be involved in
this process.
 
PMID: 18374547 [PubMed - indexed for MEDLINE]
 
 
10. Dev Dyn. 2008 Jan;237(1):216-21.
 
Myocardin expression during avian embryonic heart development requires the
endoderm but is independent of BMP signaling.
 
Warkman AS, Yatskievych TA, Hardy KM, Krieg PA, Antin PB.
 
Department of Cell Biology and Anatomy, University of Arizona, Tucson, Arizona,
USA.
 
Myocardin, a serum response factor cofactor, plays an important role in
regulating heart and smooth muscle development. To investigate myocardin function
during early stages of heart development, we isolated the chicken orthologue of
myocardin and characterized its expression between Hamburger and Hamilton stages
3 and 15. At stage 4, myocardin transcripts are detected in the lateral and
extraembryonic mesoderm, become progressively localized to the precardiac
mesoderm and the differentiated myocardium and are also seen in smooth muscle
cells of the developing vascular plexus. Surprisingly, myocardin expression
within the developing chicken embryo precedes that of the homeodomain
transcription factor Nkx2.5. Embryonic dissection studies demonstrate that
signals from the endoderm are required for myocardin expression within the
precardiac mesoderm. However, unlike Nkx2.5, myocardin expression is not
regulated by bone morphogenetic protein (BMP) signaling. These results suggest
that initial expression of myocardin in the precardiac mesoderm is regulated by a
signaling pathway that is parallel to, and independent of, Nkx2.5 expression.
 
PMID: 18069699 [PubMed - indexed for MEDLINE]
 
 
11. Development. 2007 Nov;134(22):4011-21. Epub 2007 Oct 17.
 
Reciprocal endoderm-mesoderm interactions mediated by fgf24 and fgf10 govern
pancreas development.
 
Manfroid I, Delporte F, Baudhuin A, Motte P, Neumann CJ, Voz ML, Martial JA,
Peers B.
 
GIGA-Research-Unité de Biologie Moléculaire et Génie Génétique, Tour B34,
Université de Liège, B-4000 Sart Tilman, Belgium. isabelle.manfroid@ulg.ac.be
 
In amniotes, the pancreatic mesenchyme plays a crucial role in pancreatic
epithelium growth, notably through the secretion of fibroblast growth factors.
However, the factors involved in the formation of the pancreatic mesenchyme are
still largely unknown. In this study, we characterize, in zebrafish embryos, the
pancreatic lateral plate mesoderm, which is located adjacent to the ventral
pancreatic bud and is essential for its specification and growth. We firstly show
that the endoderm, by expressing the fgf24 gene at early stages, triggers the
patterning of the pancreatic lateral plate mesoderm. Based on the expression of
isl1, fgf10 and meis genes, this tissue is analogous to the murine pancreatic
mesenchyme. Secondly, Fgf10 acts redundantly with Fgf24 in the pancreatic lateral
plate mesoderm and they are both required to specify the ventral pancreas. Our
results unveil sequential signaling between the endoderm and mesoderm that is
critical for the specification and growth of the ventral pancreas, and explain
why the zebrafish ventral pancreatic bud generates the whole exocrine tissue.
 
PMID: 17942484 [PubMed - indexed for MEDLINE]
 
 
12. Development. 2007 Jun;134(12):2207-17. Epub 2007 May 16.
 
Repression of Wnt/beta-catenin signaling in the anterior endoderm is essential
for liver and pancreas development.
 
McLin VA, Rankin SA, Zorn AM.
 
Cincinnati Children's Research Foundation, Department of Pediatrics, College of
Medicine, University of Cincinnati, 3333 Burnet Avenue, Cincinnati, OH 45229,
USA.
 
The liver and pancreas are specified from the foregut endoderm through an
interaction with the adjacent mesoderm. However, the earlier molecular mechanisms
that establish the foregut precursors are largely unknown. In this study, we have
identified a molecular pathway linking gastrula-stage endoderm patterning to
organ specification. We show that in gastrula and early-somite stage Xenopus
embryos, Wnt/beta-catenin activity must be repressed in the anterior endoderm to
maintain foregut identity and to allow liver and pancreas development. By
contrast, high beta-catenin activity in the posterior endoderm inhibits foregut
fate while promoting intestinal development. Experimentally repressing
beta-catenin activity in the posterior endoderm was sufficient to induce ectopic
organ buds that express early liver and pancreas markers. beta-catenin acts in
part by inhibiting expression of the homeobox gene hhex, which is one of the
earliest foregut markers and is essential for liver and pancreas development.
Promoter analysis indicates that beta-catenin represses hhex transcription
indirectly via the homeodomain repressor Vent2. Later in development,
beta-catenin activity has the opposite effect and enhances liver development.
These results illustrate that turning Wnt signaling off and on in the correct
temporal sequence is essential for organ formation, a finding that might directly
impact efforts to differentiate liver and pancreas tissue from stem cells.
 
PMID: 17507400 [PubMed - indexed for MEDLINE]
 
 
13. Int Rev Cytol. 2007;259:49-111.
 
Molecular basis of vertebrate endoderm development.
 
Zorn AM, Wells JM.
 
Division of Developmental Biology, Cincinnati Children's Hospital Research,
Foundation and University of Cincinnati College of Medicine, Cincinnati, Ohio
45229, USA.
 
The embryonic endoderm gives rise to the epithelial lining of the digestive and
respiratory systems and organs such as the thyroid, lungs, liver, gallbladder,
and pancreas. Studies in Xenopus, zebrafish, and mice have revealed a conserved
molecular pathway controlling vertebrate endoderm development. The TGFbeta/Nodal
signaling pathway is at the top of this molecular hierarchy and controls the
expression of a number of key transcription factors including Mix-like
homeodomain proteins, Gata zinc finger factors, Sox HMG domain proteins, and Fox
forkhead factors. Here we review the function of these molecules comparing and
contrasting their roles in each model organism. Finally, we will describe how our
understanding of the molecular pathway governing endoderm development in embryos
is being used to differentiate embryonic stem cells in vitro along endodermal
lineages, with the ultimate goal of making therapeutically useful tissue.
 
PMID: 17425939 [PubMed - indexed for MEDLINE]




14. Stem Cells Dev. 2007 Feb;16(1):3-5.
2: Holtzinger A, Rosenfeld GE, Evans T. Gata4 directs development of
cardiac-inducing endoderm from ES cells. Dev Biol. 2010 Jan 1;337(1):63-73. Epub
2009 Oct 20. PubMed PMID: 19850025; PubMed Central PMCID: PMC2799892.


Heart development: the battle between mesoderm and endoderm.


Pal R, Khanna A.
3: Zorn AM, Wells JM. Vertebrate endoderm development and organ formation. Annu
Rev Cell Dev Biol. 2009;25:221-51. Review. PubMed PMID: 19575677; PubMed Central
PMCID: PMC2861293.


Embryonic Stem Cell Group, Reliance Life Sciences Pvt. Ltd. Dhirubhai Ambani Life
Sciences Center, Navi Mumbai, India.


Recent years have seen a surge of scientific research examining the
4: Yang DH, Smith ER, Cai KQ, Xu XX. C-Fos elimination compensates for disabled-2
interdependence of one germ layer in the development of the other, both in vivo
requirement in mouse extraembryonic endoderm development. Dev Dyn. 2009
and in vitro. For example, the endoderm is believed to play a crucial role in the
Mar;238(3):514-23. PubMed PMID: 19191218; PubMed Central PMCID: PMC2743073.
formation of mesoderm and subsequent maturation of cells belonging to the
mesodermal lineage. Our understanding of this complex relationship is
continuously growing with reinterpretation of earlier concepts and apprehension
of newer hypotheses into the biology of embryonic development. Here we discuss
some of the events governing the cooperative control of endoderm over mesoderm,
and propose a perspective based on the existing literature and our own
experience.


PMID: 17348801 [PubMed - indexed for MEDLINE]


5: Yagi Y, Ito Y, Kuhara S, Tashiro K. Cephalic hedgehog expression is regulated
directly by Sox17 in endoderm development of Xenopus laevis. Cytotechnology. 2008
Jun;57(2):151-9. Epub 2008 Feb 12. PubMed PMID: 19003160; PubMed Central PMCID:
PMC2553669.


15. Proc Natl Acad Sci U S A. 2006 Aug 1;103(31):11607-12. Epub 2006 Jul 25.


An early role for sonic hedgehog from foregut endoderm in jaw development:
6: Soares ML, Torres-Padilla ME, Zernicka-Goetz M. Bone morphogenetic protein 4
ensuring neural crest cell survival.
signaling regulates development of the anterior visceral endoderm in the mouse
embryo. Dev Growth Differ. 2008 Sep;50(7):615-21. PubMed PMID: 18657169.


Brito JM, Teillet MA, Le Douarin NM.


Laboratoire de Développement, Evolution et Plasticité du Système Nerveux, Unité
7: Reichenbach B, Delalande JM, Kolmogorova E, Prier A, Nguyen T, Smith CM,
Propre de Recherche 2197, Centre National de la Recherche Scientifique, Institut
Holzschuh J, Shepherd IT. Endoderm-derived Sonic hedgehog and mesoderm Hand2
de Neurobiologie Alfred Fessard, F-91198 Gif-sur-Yvette, France.
expression are required for enteric nervous system development in zebrafish. Dev
Biol. 2008 Jun 1;318(1):52-64. Epub 2008 Mar 20. PubMed PMID: 18436202; PubMed
Central PMCID: PMC2435286.


We have investigated the role of Sonic hedgehog (Shh) in the development of
facial structures by depriving chicken embryos of the most anterior sources of
this morphogen, including the prechordal plate and the anterior ventral endoderm
of the foregut, before the onset of neural crest cell (NCC) migration to the
first branchial arch (BA1). The entire forehead, including the foregut endoderm,
was removed at 5- to 10-somite stage (ss), which led to the absence of the lower
jaw when the operation was performed before 7-ss. If the embryos were deprived of
their forehead at 8- to 10-ss, they were later on endowed with a lower beak. In
embryos that were operated on early, the NCCs migrated normally to BA1 but were
subjected to massive apoptosis a few hours later. Cell death did not occur when
forehead excision was performed at a later stage. In this case, onward expression
of Shh in the ventral foregut endoderm extended caudally over the excision limit,
and we hypothesized that absence of Shh production by the endoderm in embryos
that were operated on early could be responsible for the NCC apoptosis and the
failure of BA1 development. We thus provided exogenous Shh to the embryos that
were operated on before 7-ss. In this case, the development of the lower jaw was
rescued. Therefore, Shh derived from the ventral foregut endoderm ensures the
survival of NCCs at a critical stage of BA1 development.


PMCID: PMC1544217
8: Shin CH, Chung WS, Hong SK, Ober EA, Verkade H, Field HA, Huisken J, Stainier
PMID: 16868080 [PubMed - indexed for MEDLINE]
DY. Multiple roles for Med12 in vertebrate endoderm development. Dev Biol. 2008
May 15;317(2):467-79. Epub 2008 Mar 4. PubMed PMID: 18394596; PubMed Central
PMCID: PMC2435012.




16. Dev Growth Differ. 2006 Jun;48(5):283-95.
9: Matsushita S, Urase K, Komatsu A, Scotting PJ, Kuroiwa A, Yasugi S. Foregut
endoderm is specified early in avian development through signal(s) emanating from
Hensen's node or its derivatives. Mech Dev. 2008 May-Jun;125(5-6):377-95. Epub
2008 Feb 20. PubMed PMID: 18374547.


Development of the endoderm and gut in medaka, Oryzias latipes.


Kobayashi D, Jindo T, Naruse K, Takeda H.
10: Warkman AS, Yatskievych TA, Hardy KM, Krieg PA, Antin PB. Myocardin
expression during avian embryonic heart development requires the endoderm but is
independent of BMP signaling. Dev Dyn. 2008 Jan;237(1):216-21. PubMed PMID:
18069699.


Department of Biological Sciences, Graduate School of Science, University of
Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.


We performed an extensive analysis of endodermal development and gut tube
11: Manfroid I, Delporte F, Baudhuin A, Motte P, Neumann CJ, Voz ML, Martial JA,  
morphogenesis in the medaka embryo by histology and in situ hybridization. The
Peers B. Reciprocal endoderm-mesoderm interactions mediated by fgf24 and fgf10
markers used in these analyses included sox17, sox32, foxA2, gata-4, -5, -6 and
govern pancreas development. Development. 2007 Nov;134(22):4011-21. Epub 2007 Oct
shh. sox17, sox32, foxA2, and gata-5 and -6 are expressed in the early endoderm
17. PubMed PMID: 17942484.
to the onset of gut tube formation. Sections of medaka embryos hybridized with
foxA2, a pan-endodermal marker during gut morphogenesis, demonstrated that gut
tube formation is initiated in the anterior portion and that the anterior and
mid/posterior gut undergo distinct morphogenetic processes. Tube formation in the
anterior endoderm that is fated to the pharynx and esophagus is much delayed and
appears to be independent of gut morphogenesis. The overall aspects of medaka gut
development are similar to those of zebrafish, except that zebrafish tube
formation initiates at both the anterior and posterior portions. Our results
therefore describe both molecular and morphological aspects of medaka digestive
system development that will be necessary for the characterization of medaka
mutants.


PMID: 16759279 [PubMed - indexed for MEDLINE]


12: McLin VA, Rankin SA, Zorn AM. Repression of Wnt/beta-catenin signaling in the
anterior endoderm is essential for liver and pancreas development. Development.
2007 Jun;134(12):2207-17. Epub 2007 May 16. PubMed PMID: 17507400.


17. Dev Dyn. 2006 Sep;235(9):2549-58.


Tg(Afp-GFP) expression marks primitive and definitive endoderm lineages during
13: Zorn AM, Wells JM. Molecular basis of vertebrate endoderm development. Int
mouse development.
Rev Cytol. 2007;259:49-111. Review. PubMed PMID: 17425939.


Kwon GS, Fraser ST, Eakin GS, Mangano M, Isern J, Sahr KE, Hadjantonakis AK,
Baron MH.


Developmental Biology Program, Sloan-Kettering Institute, New York, New York
14: Pal R, Khanna A. Heart development: the battle between mesoderm and endoderm.
10021, USA.
Stem Cells Dev. 2007 Feb;16(1):3-5. PubMed PMID: 17348801.


Alpha-fetoprotein (Afp) is the most abundant serum protein in the developing
embryo. It is secreted by the visceral endoderm, its derivative yolk sac
endoderm, fetal liver hepatocytes, and the developing gut epithelium. The
abundance of this protein suggested that Afp gene regulatory elements might serve
to effectively drive reporter gene expression in developing endodermal tissues.
To this end, we generated transgenic mouse lines Tg(Afp-GFP) using an Afp
promoter/enhancer to drive expression of green fluorescent protein (GFP). Bright
GFP fluorescence allowed the visualization, in real time, of visceral endoderm,
yolk sac endoderm, fetal liver hepatocytes, and the epithelium of the gut and
pancreas. Comparison of the localization of green fluorescence with that of
endogenous Afp transcripts and protein indicated that the regulatory elements
used to generate these mouse lines directed transgene expression in what appeared
to be all Afp-expressing cells of the embryo, but only in a subset of fetal liver
cells. The bright GFP signal permitted flow cytometric analysis of fetal liver
hepatocytes. These mice represent a valuable resource for live imaging as well as
identification, quantitation, and isolation of cells from the primitive and
definitive endoderm lineages of the developing mouse embryo. Copyright 2006
Wiley-Liss, Inc.


PMCID: PMC1850385
15: Brito JM, Teillet MA, Le Douarin NM. An early role for sonic hedgehog from
PMID: 16708394 [PubMed - indexed for MEDLINE]
foregut endoderm in jaw development: ensuring neural crest cell survival. Proc
Natl Acad Sci U S A. 2006 Aug 1;103(31):11607-12. Epub 2006 Jul 25. PubMed PMID:  
16868080; PubMed Central PMCID: PMC1544217.




18. Biochem Biophys Res Commun. 2006 Jun 9;344(3):852-8. Epub 2006 Apr 19.
16: Kobayashi D, Jindo T, Naruse K, Takeda H. Development of the endoderm and gut
in medaka, Oryzias latipes. Dev Growth Differ. 2006 Jun;48(5):283-95. PubMed
PMID: 16759279.


Changes in S1P1 and S1P2 expression during embryonal development and primitive
endoderm differentiation of F9 cells.


Hiraga Y, Kihara A, Sano T, Igarashi Y.
17: Kwon GS, Fraser ST, Eakin GS, Mangano M, Isern J, Sahr KE, Hadjantonakis AK,
Baron MH. Tg(Afp-GFP) expression marks primitive and definitive endoderm lineages
during mouse development. Dev Dyn. 2006 Sep;235(9):2549-58. PubMed PMID:
16708394; PubMed Central PMCID: PMC1850385.


Department of Biomembrane and Biofunctional Chemistry, Graduate School of
Pharmaceutical Sciences, Hokkaido University, Kita 12-jo, Nishi 6-choume,
Kita-ku, Sapporo 060-0812, Japan.


Sphingosine 1-phosphate (S1P) is a ligand for S1P family receptors
18: Hiraga Y, Kihara A, Sano T, Igarashi Y. Changes in S1P1 and S1P2 expression
(S1P(1)-S1P(5)). Of these receptors, S1P(1), S1P(2), and S1P(3) are ubiquitously
during embryonal development and primitive endoderm differentiation of F9 cells.  
expressed in adult mice, while S1P(4) and S1P(5) are tissue specific. However,
Biochem Biophys Res Commun. 2006 Jun 9;344(3):852-8. Epub 2006 Apr 19. PubMed
little is known of their expression during embryonal development. We performed
PMID: 16631609.
Northern blot analyses in mouse embryonal tissue and found that such expression
is developmentally regulated. We also examined the expression of these receptors
during primitive endoderm (PrE) differentiation of mouse F9 embryonal carcinoma
(EC) cells, a well-known in vitro endoderm differentiation system. S1P(2) mRNA
was abundantly expressed in F9 EC cells, but little S1P(1) and no S1P(3), S1P(4),
or S1P(5) mRNA was detectable. However, S1P(1) mRNA expression was induced during
EC-to-PrE differentiation. Studies using small interference RNA of S1P(1)
indicated that increased S1P(1) expression is required for PrE differentiation.
Thus, S1P(1) may play an important function in PrE differentiation that is not
substituted for by S1P(2).


PMID: 16631609 [PubMed - indexed for MEDLINE]


19: Bohnsack BL, Lai L, Northrop JL, Justice MJ, Hirschi KK. Visceral endoderm
function is regulated by quaking and required for vascular development. Genesis.
2006 Feb;44(2):93-104. PubMed PMID: 16470614.


19. Genesis. 2006 Feb;44(2):93-104.


Visceral endoderm function is regulated by quaking and required for vascular
20: Bort R, Signore M, Tremblay K, Martinez Barbera JP, Zaret KS. Hex homeobox
development.
gene controls the transition of the endoderm to a pseudostratified, cell emergent
epithelium for liver bud development. Dev Biol. 2006 Feb 1;290(1):44-56. Epub
2005 Dec 20. PubMed PMID: 16364283.


Bohnsack BL, Lai L, Northrop JL, Justice MJ, Hirschi KK.


Department of Molecular and Cellular Biology, Baylor College of Medicine,
21: Doherty JR, Zhu H, Kuliyev E, Mead PE. Determination of the minimal domains
Houston, Texas 77030, USA.
of Mix.3/Mixer required for endoderm development. Mech Dev. 2006
Jan;123(1):56-66. Epub 2005 Dec 5. PubMed PMID: 16330190.


The quaking (qkI) gene produces three major alternatively spliced variants
(qkI-5,-6,-7) that encode for proteins that share the RNA binding, KH domain.
Previous studies utilizing the qk(k2) allele, which contains an
N-ethyl-N-nitrosourea (ENU)-induced point mutation in the KH domain, demonstrate
that this functional region of qkI is required for embryonic vascular
development. In the current studies we demonstrate that qk(l-1)/qk(l-1) mutants,
which lack the QKI-5 splice variant, also died at midgestation due to vascular
remodeling defects. In addition, although all three QKI isoforms were expressed
in the visceral endoderm of wildtype yolk sacs, qkI-6 and qkI-7 transcript and
protein expression were suppressed in qk(k2)/qk(k2) and qk(l-1)/qk(l-1) mutant
yolk sacs, suggesting that the KH-domain of QKI-5 was required for qkI-6 and
qkI-7 expression. Further studies revealed that the cellular role of qkI is to
regulate visceral endoderm function, including the local synthesis of retinoic
acid (RA) and the subsequent control of endothelial cell proliferation, matrix
production, and visceral endoderm survival. Although these defects were rescued
by exogenous RA, visceral endoderm function or vascular remodeling were not
restored. Thus, we conclude that qkI regulates visceral endoderm function, which
is critical for vascular remodeling.


PMID: 16470614 [PubMed - indexed for MEDLINE]
22: Murakami R, Okumura T, Uchiyama H. GATA factors as key regulatory molecules
in the development of Drosophila endoderm. Dev Growth Differ. 2005
Dec;47(9):581-9. Review. PubMed PMID: 16316403.




20. Dev Biol. 2006 Feb 1;290(1):44-56. Epub 2005 Dec 20.
23: Graham A, Okabe M, Quinlan R. The role of the endoderm in the development and
evolution of the pharyngeal arches. J Anat. 2005 Nov;207(5):479-87. Review.
PubMed PMID: 16313389; PubMed Central PMCID: PMC1571564.


Hex homeobox gene controls the transition of the endoderm to a pseudostratified,
cell emergent epithelium for liver bud development.


Bort R, Signore M, Tremblay K, Martinez Barbera JP, Zaret KS.
24: Dickinson K, Leonard J, Baker JC. Genomic profiling of mixer and Sox17beta
targets during Xenopus endoderm development. Dev Dyn. 2006 Feb;235(2):368-81.
PubMed PMID: 16278889.


Cell and Developmental Biology Program, Fox Chase Cancer Center, 333 Cottman
Avenue, Philadelphia, PA 19111, USA.


Little is known about the mechanism by which embryonic liver, lung, and pancreas
25: Matsuura R, Kogo H, Ogaeri T, Miwa T, Kuwahara M, Kanai Y, Nakagawa T,
progenitor cells emerge from the endodermal epithelium to initiate organogenesis.
Kuroiwa A, Fujimoto T, Torihashi S. Crucial transcription factors in endoderm and
Understanding this process and its genetic control provides insight into
embryonic gut development are expressed in gut-like structures from mouse ES
ontogeny, developmental abnormalities, and tissue regeneration. We find that
cells. Stem Cells. 2006 Mar;24(3):624-30. Epub 2005 Oct 6. PubMed PMID: 16210401.
shortly after hepatic endoderm cells are specified, they undergo a transition
from a columnar, gut morphology to a pseudostratified morphology, with
concomitant "interkinetic nuclear migration" (INM) during cell division. INM is a
hallmark of pseudostratified epithelia and the process used by neural progenitors
to emerge from the neural epithelium. We find that the transition of the hepatic
endoderm, but not the neural epithelium, to a pseudostratified epithelium is
dependent upon the cell-autonomous activity of the homeobox gene Hex. In the
absence of Hex, hepatic endoderm cells survive but maintain a columnar, simple
epithelial phenotype and ectopically express Shh and other genes characteristic
of the midgut epithelium. Thus, Hex promotes endoderm organogenesis by promoting
the transition to a pseudostratified epithelium, which in turn allows
hepatoblasts to emerge into the stromal environment and continue differentiating.


PMID: 16364283 [PubMed - indexed for MEDLINE]


26: Fukuda K, Kikuchi Y. Endoderm development in vertebrates: fate mapping,
induction and regional specification. Dev Growth Differ. 2005 Aug;47(6):343-55.
Review. PubMed PMID: 16109032.


21. Mech Dev. 2006 Jan;123(1):56-66. Epub 2005 Dec 5.


Determination of the minimal domains of Mix.3/Mixer required for endoderm
27: Maduro MF, Kasmir JJ, Zhu J, Rothman JH. The Wnt effector POP-1 and the
development.
PAL-1/Caudal homeoprotein collaborate with SKN-1 to activate C. elegans endoderm  
development. Dev Biol. 2005 Sep 15;285(2):510-23. PubMed PMID: 16084508.


Doherty JR, Zhu H, Kuliyev E, Mead PE.


Department of Pathology, St Jude Children's Research Hospital, 332 North
28: Crump JG, Swartz ME, Kimmel CB. An integrin-dependent role of pouch endoderm
Lauderdale Street, Memphis, TN 38105, USA.
in hyoid cartilage development. PLoS Biol. 2004 Sep;2(9):E244. Epub 2004 Jul 20.
PubMed PMID: 15269787; PubMed Central PMCID: PMC479042.


The Mix/Bix family of Pax-like homeodomain transcription factors is expressed
early in vertebrate development and play important roles in endoderm and mesoderm
formation. Like other Pax-related homeodomain proteins, the Mix/Bix family binds
DNA as monomers or dimers and dimerization is mediated by the homeodomain. While
the Mix/Bix family shares extensive sequence homology within the DNA-binding
homeodomain, ectopic expression of these proteins has profoundly different
outcomes. Expression of Xenopus Mix.3/Mixer in explanted ectoderm results in
endoderm differentiation, whereas Mix.1 expression does not. In this study we
sought to define the domains of Mix.3/Mixer that are responsible for this
endoderm inducing activity. We generated domain swap mutants between Mix.3/Mixer
and Mix.1 and tested their ability to induce endoderm in explanted ectoderm. We
demonstrate that the homeodomain and sixty-two amino acids in the carboxyl
terminus are required to induce endoderm and that these domains must be on the
same polypeptide and can not act in trans as a heterodimer. A Smad2 interaction
motif in Mix.3/Mixer is involved in endoderm differentiation but is not
essential. Thus, we have defined the regions of Mix.3/Mixer that confer
endoderm-inducing activity. These studies reveal a novel co-operation between the
homeodomain and a small domain in the carboxyl terminal region that is essential
for Mix.3/Mixer function.


PMID: 16330190 [PubMed - indexed for MEDLINE]
29: Kubo A, Shinozaki K, Shannon JM, Kouskoff V, Kennedy M, Woo S, Fehling HJ,
Keller G. Development of definitive endoderm from embryonic stem cells in
culture. Development. 2004 Apr;131(7):1651-62. Epub 2004 Mar 3. PubMed PMID:
14998924.




22. Dev Growth Differ. 2005 Dec;47(9):581-9.
30: Ober EA, Olofsson B, Mäkinen T, Jin SW, Shoji W, Koh GY, Alitalo K, Stainier
DY. Vegfc is required for vascular development and endoderm morphogenesis in
zebrafish. EMBO Rep. 2004 Jan;5(1):78-84. PubMed PMID: 14710191; PubMed Central
PMCID: PMC1298958.


GATA factors as key regulatory molecules in the development of Drosophila
endoderm.


Murakami R, Okumura T, Uchiyama H.
31: Berger TM, Hirsch E, Djonov V, Schittny JC. Loss of beta1-integrin-deficient
cells during the development of endoderm-derived epithelia. Anat Embryol (Berl).
2003 Dec;207(4-5):283-8. Epub 2003 Nov 25. PubMed PMID: 14648219.


Department of Physics, Biology, and Informatics, Yamaguchi University, Yamaguchi
753-8512, Japan. ryu@yamaguchi-u.ac.jp


Essential roles for GATA factors in the development of endoderm have been
32: Macatee TL, Hammond BP, Arenkiel BR, Francis L, Frank DU, Moon AM. Ablation
reported in various animals. A Drosophila GATA factor gene, serpent (srp, dGATAb,
of specific expression domains reveals discrete functions of ectoderm- and
ABF), is expressed in the prospective endoderm, and loss of srp activity causes
endoderm-derived FGF8 during cardiovascular and pharyngeal development.
transformation of the prospective endoderm into ectodermal foregut and hindgut,
Development. 2003 Dec;130(25):6361-74. PubMed PMID: 14623825; PubMed Central
indicating that srp acts as a selector gene to specify the developmental fate of
PMCID: PMC1876660.
the endoderm. While srp is expressed in the endoderm only during early stages, it
activates a subsequent GATA factor gene, dGATAe, and the latter continues to be
expressed specifically in the endoderm throughout life. dGATAe activates various
functional genes in the differentiated endodermal midgut. An analogous mode of
regulation has been reported in Caenorhabditis elegans, in which a pair of GATA
genes, end-1/3, specifies endodermal fate, and a downstream pair of GATA genes,
elt-2/7, activates genes in the differentiated endoderm. Functional homology of
GATA genes in nature is apparently extendable to vertebrates, because endodermal
GATA genes of C. elegans and Drosophila induce endoderm development in Xenopus
ectoderm. These findings strongly imply evolutionary conservation of the roles of
GATA factors in the endoderm across the protostomes and the deuterostomes.


PMID: 16316403 [PubMed - indexed for MEDLINE]


33: Hinman VF, Nguyen AT, Davidson EH. Expression and function of a starfish Otx
ortholog, AmOtx: a conserved role for Otx proteins in endoderm development that
predates divergence of the eleutherozoa. Mech Dev. 2003 Oct;120(10):1165-76.
PubMed PMID: 14568105.


23. J Anat. 2005 Nov;207(5):479-87.


The role of the endoderm in the development and evolution of the pharyngeal
34: Finley KR, Tennessen J, Shawlot W. The mouse secreted frizzled-related
arches.
protein 5 gene is expressed in the anterior visceral endoderm and foregut
endoderm during early post-implantation development. Gene Expr Patterns. 2003
Oct;3(5):681-4. PubMed PMID: 12972006.


Graham A, Okabe M, Quinlan R.


MRC Centre for Developmental Neurobiology, Guys Campus, Kings College London,
35: Tam PP, Kanai-Azuma M, Kanai Y. Early endoderm development in vertebrates:
London, UK. anthony.graham@kcl.ac.uk
lineage differentiation and morphogenetic function. Curr Opin Genet Dev. 2003
Aug;13(4):393-400. Review. PubMed PMID: 12888013.


The oro-pharyngeal apparatus has its origin in a series of bulges found on the
lateral surface of the embryonic head, the pharyngeal arches. Significantly, the
development of these structures is extremely complex, involving interactions
between a number of disparate embryonic cell types: ectoderm, endoderm, mesoderm
and neural crest, each of which generates particular components of the arches,
and whose development must be co-ordinated to generate the functional adult
oro-pharyngeal apparatus. In the past most studies have emphasized the role
played by the neural crest, which generates the skeletal elements of the arches,
in directing pharyngeal arch development. However, it is now apparent that the
pharyngeal endoderm plays an important role in directing arch development. Here
we discuss the role of the pharyngeal endoderm in organizing the development of
the pharyngeal arches, and the mechanisms that act to pattern the endoderm itself
and those which direct its morphogenesis. Finally, we discuss the importance of
modification to the pharyngeal endoderm during vertebrate evolution. In
particular, we focus on the emergence of the parathyroid gland, which we have
recently shown to be the result of the internalization of the gills.


PMCID: PMC1571564
36: Goldin SN, Papaioannou VE. Paracrine action of FGF4 during periimplantation
PMID: 16313389 [PubMed - indexed for MEDLINE]
development maintains trophectoderm and primitive endoderm. Genesis. 2003
May;36(1):40-7. PubMed PMID: 12748966.




24. Dev Dyn. 2006 Feb;235(2):368-81.
37: Pera EM, Martinez SL, Flanagan JJ, Brechner M, Wessely O, De Robertis EM.
 
Genomic profiling of mixer and Sox17beta targets during Xenopus endoderm
development.
 
Dickinson K, Leonard J, Baker JC.
 
Department of Genetics, Stanford University Medical School, Stanford, California
94062, USA.
 
The transcription factors Mixer and Sox17beta have well-characterized roles in
endoderm specification during Xenopus embryogenesis. In order to more thoroughly
understand the mechanisms by which these endodermal regulators act, we expressed
Mixer and Sox17beta in naïve ectodermal tissue and, using oligonucleotide-based
microarrays, compared their genomic transcriptional profile to that of unaffected
tissue. Using this approach, we identified 71 transcripts that are upregulated by
Mixer or Sox17beta, 63 of which have previously uncharacterized roles in endoderm
development. Furthermore, an in situ hybridization screen using antisense probes
for several of these clones identified six targets of Mixer and/or Sox17beta that
are expressed in the endoderm during gastrula stages, providing new and regional
markers of the endoderm. Our results contribute further insight into the
functions of Mixer and Sox17beta and bring us closer to understanding at the
molecular level the pathways that regulate endoderm development. Copyright 2005
Wiley-Liss, Inc.
 
PMID: 16278889 [PubMed - indexed for MEDLINE]
 
 
25. Stem Cells. 2006 Mar;24(3):624-30. Epub 2005 Oct 6.
 
Crucial transcription factors in endoderm and embryonic gut development are
expressed in gut-like structures from mouse ES cells.
 
Matsuura R, Kogo H, Ogaeri T, Miwa T, Kuwahara M, Kanai Y, Nakagawa T, Kuroiwa A,
Fujimoto T, Torihashi S.
 
Department of Anatomy and Molecular Cell Biology, Graduate School of Medicine,
Nagoya University, Japan.
 
Mouse embryonic stem (ES) cells are pluripotent and retain the potential to form
an organ similar to the gut showing spontaneous contractions in vitro. The
morphological features of these structures and their formation, as assessed using
the hanging drop method to produce embryoid bodies (EBs), seem to be similar to
those in vivo. To determine whether the same molecular mechanisms are involved in
the formation process, the expression pattern of transcription factors regulating
endoderm and gut development in the mouse embryo was examined by in situ
hybridization and compared with in vivo expression. Expression of gene products
was also examined by immunohistochemistry, and expression colocalization was
analyzed with double staining. The results showed that all factors examined, that
is, Sox17, Id2, HNF3beta/Foxa2, and GATA4, were expressed in both EBs and
gut-like structures. Moreover, their expression patterns were similar to those in
the mouse embryo. EBs after the hanging drop period and before outgrowth already
expressed all factors that were colocalized with each other in EB epithelial
structures. These findings suggest that the origin of the gut-like structure is
determined during the hanging drop period and that the gut-like structure is
formed as the epithelial structure in EBs during the hanging drop period. They
also indicate that the in vitro system using mouse ES cells mimics in vivo
development and should prove useful in the study of molecular mechanisms for
endoderm and gut development.
 
PMID: 16210401 [PubMed - indexed for MEDLINE]
 
 
26. Dev Growth Differ. 2005 Aug;47(6):343-55.
 
Endoderm development in vertebrates: fate mapping, induction and regional
specification.
 
Fukuda K, Kikuchi Y.
 
Department of Biological Sciences, Tokyo Metropolitan University, 1-1
Minamiohsawa, Hachioji, Tokyo 192-0397, Japan.
 
The formation of the vertebrate body plan begins with the differentiation of
cells into three germ layers: ectoderm, mesoderm and endoderm. Cells in the
endoderm give rise to the epithelial lining of the digestive tract, associated
glands and respiratory system. One of the fundamental problems in developmental
biology is to elucidate how these three primary germ layers are established from
the homologous population of cells in the early blastomere. To address this
question, ectoderm and mesoderm development have been extensively analyzed, but
study of endoderm development has only begun relatively recently. In this review,
we focus on the 'where', 'when' and 'how' of endoderm development in four
vertebrate model organisms: the zebrafish, Xenopus, chick and mouse. We discuss
the classical fate mapping of the endoderm and the more recent progress in
characterizing its induction, segregation and regional specification.
 
PMID: 16109032 [PubMed - indexed for MEDLINE]
 
 
27. Dev Biol. 2005 Sep 15;285(2):510-23.
 
The Wnt effector POP-1 and the PAL-1/Caudal homeoprotein collaborate with SKN-1
to activate C. elegans endoderm development.
 
Maduro MF, Kasmir JJ, Zhu J, Rothman JH.
 
Department of MCD Biology and Neuroscience Research Institute, University of
California at Santa Barbara, Santa Barbara, CA 93106, USA.
 
POP-1, a Tcf/Lef-1-like target of the convergent Wnt and MAP kinase (MAPK)
signaling pathways, functions throughout Caenorhabditis elegans development to
generate unequal daughters during asymmetric cell divisions. A particularly
prominent such asymmetric division occurs when the EMS blastomere divides to
produce MS, a mesoderm precursor, and E, the sole endoderm progenitor. POP-1
allows mesoderm development in the MS lineage by repressing the
endoderm-promoting end-1 and end-3 genes. This repression is relieved in the E
lineage by Wnt/MAPK signaling, which results in phosphorylation and export of
POP-1 from the E nucleus. Here, we report that, in addition to repressing E
development in MS, POP-1 also functions positively in endoderm development, in
conjunction with the well-characterized endoderm-promoting SKN-1-->MED regulatory
cascade. While removal of POP-1 alone results in derepression of endoderm
development in the MS lineage, mutations in several genes that result in
impenetrant loss of endoderm are strongly enhanced by loss of pop-1 function. A
Lef-1-like binding site is essential for activation of an end-1 promoter fusion,
suggesting that POP-1 may act directly on end-1. Thus, POP-1 may generate
developmental asymmetry during many cell divisions in C. elegans by reiteratively
switching from repressive and activating states. Furthermore, we report that the
Caudal-like homeodomain protein PAL-1, whose role in early embryogenesis was
thought to be exclusive specification of mesectodermal development in the lineage
of the C blastomere, can act with POP-1 to activate endoderm specification in the
absence of the SKN-1-->MED transcriptional input, accounting for the impenetrance
of mutants lacking SKN-1 or MED-1,2 activity. We conclude that the combined
action of several separate transcriptional regulatory inputs, including SKN-1,
the MEDs, PAL-1, and the Wnt/MAPK-activated form of POP-1, are responsible for
activating end gene transcription and endoderm development.
 
PMID: 16084508 [PubMed - indexed for MEDLINE]
 
 
28. PLoS Biol. 2004 Sep;2(9):E244. Epub 2004 Jul 20.
 
An integrin-dependent role of pouch endoderm in hyoid cartilage development.
 
Crump JG, Swartz ME, Kimmel CB.
 
Institute of Neuroscience, University of Oregon, Eugene, Oregon, USA.
gage@uoneuro.uoregon.edu
 
Pharyngeal endoderm is essential for and can reprogram development of the head
skeleton. Here we investigate the roles of specific endodermal structures in
regulating craniofacial development. We have isolated an integrinalpha5 mutant in
zebrafish that has region-specific losses of facial cartilages derived from hyoid
neural crest cells. In addition, the cranial muscles that normally attach to the
affected cartilage region and their associated nerve are secondarily reduced in
integrinalpha5- animals. Earlier in development, integrinalpha5 mutants also have
specific defects in the formation of the first pouch, an outpocketing of the
pharyngeal endoderm. By fate mapping, we show that the cartilage regions that are
lost in integrinalpha5 mutants develop from neural crest cells directly adjacent
to the first pouch in wild-type animals. Furthermore, we demonstrate that
Integrinalpha5 functions in the endoderm to control pouch formation and cartilage
development. Time-lapse recordings suggest that the first pouch promotes
region-specific cartilage development by regulating the local compaction and
survival of skeletogenic neural crest cells. Thus, our results reveal a hierarchy
of tissue interactions, at the top of which is the first endodermal pouch, which
locally coordinates the development of multiple tissues in a specific region of
the vertebrate face. Lastly, we discuss the implications of a mosaic assembly of
the facial skeleton for the evolution of ray-finned fish.
 
PMCID: PMC479042
PMID: 15269787 [PubMed - indexed for MEDLINE]
 
 
29. Development. 2004 Apr;131(7):1651-62. Epub 2004 Mar 3.
 
Development of definitive endoderm from embryonic stem cells in culture.
 
Kubo A, Shinozaki K, Shannon JM, Kouskoff V, Kennedy M, Woo S, Fehling HJ, Keller
G.
 
The Carl C. Icahn Center for Gene Therapy and Molecular Medicine, Mount Sinai
School of Medicine, New York, NY 10029, USA.
 
The cellular and molecular events regulating the induction and tissue-specific
differentiation of endoderm are central to our understanding of the development
and function of many organ systems. To define and characterize key components in
this process, we have investigated the potential of embryonic stem (ES) cells to
generate endoderm following their differentiation to embryoid bodies (EBs) in
culture. We found that endoderm can be induced in EBs, either by limited exposure
to serum or by culturing in the presence of activin A (activin) under serum-free
conditions. By using an ES cell line with the green fluorescent protein (GFP)
cDNA targeted to the brachyury locus, we demonstrate that endoderm develops from
a brachyury(+) population that also displays mesoderm potential. Transplantation
of cells generated from activin-induced brachyury(+) cells to the kidney capsule
of recipient mice resulted in the development of endoderm-derived structures.
These findings demonstrate that ES cells can generate endoderm in culture and, as
such, establish this differentiation system as a unique murine model for studying
the development and specification of this germ layer.
 
PMID: 14998924 [PubMed - indexed for MEDLINE]
 
 
30. EMBO Rep. 2004 Jan;5(1):78-84.
 
Vegfc is required for vascular development and endoderm morphogenesis in
zebrafish.
 
Ober EA, Olofsson B, Mäkinen T, Jin SW, Shoji W, Koh GY, Alitalo K, Stainier DY.
 
Department of Biochemistry and Biophysics, Programs in Developmental Biology,
Genetics and Human Genetics, University of California, San Francisco, California
94143-0448, USA.
 
During embryogenesis, complex morphogenetic events lead endodermal cells to
coalesce at the midline and form the primitive gut tube and associated organs.
While several genes have recently been implicated in endoderm differentiation, we
know little about the genes that regulate endodermal morphogenesis. Here, we show
that vascular endothelial growth factor C (Vegfc), an angiogenic as well as a
lymphangiogenic factor, is unexpectedly involved in this process in zebrafish.
Reducing Vegfc levels using morpholino antisense oligonucleotides, or through
overexpression of a soluble form of the VEGFC receptor, VEGFR-3, affects the
coalescence of endodermal cells in the anterior midline, leading to the formation
of a forked gut tube and the duplication of the liver and pancreatic buds.
Further analyses indicate that Vegfc is additionally required for the initial
formation of the dorsal endoderm. We also demonstrate that Vegfc is required for
vasculogenesis as well as angiogenesis in the zebrafish embryo. These data argue
for a requirement of Vegfc in the developing vasculature and, more surprisingly,
implicate Vegfc signalling in two distinct steps during endoderm development,
first during the initial differentiation of the dorsal endoderm, and second in
the coalescence of the anterior endoderm to the midline.
 
PMCID: PMC1298958
PMID: 14710191 [PubMed - indexed for MEDLINE]
 
 
31. Anat Embryol (Berl). 2003 Dec;207(4-5):283-8. Epub 2003 Nov 25.
 
Loss of beta1-integrin-deficient cells during the development of endoderm-derived
epithelia.
 
Berger TM, Hirsch E, Djonov V, Schittny JC.
 
Institute of Anatomy, University of Bern, Buehlstrasse 26, 3000 Bern 9,
Switzerland.
 
Beta1-integrins (beta1) represent cell surface receptors which mediate
cell-matrix and cell-cell interactions. Fässler and Meyer described chimeric mice
containing transgenic cells that express the LacZ gene instead of the beta1 gene.
They observed beta1-negative cells in all germ layers at embryonic day E 8.5.
Later in development, using a glucose phosphate isomerase assay of homogenized
tissue samples, high levels of transgenic cells were found in skeletal muscle and
gut, low levels in lung, heart, and kidney and none in the liver and spleen
(Fässler and Meyer 1995). In order to study which cell types require beta1 during
development of the primitive gut including its derivatives, chimeric fetuses
containing 15 to 25% transgenic cells were obtained at days E 14.5 and E 15.5.
They were LacZ (beta-galactosidase) stained "en bloc" and cross-sectioned head to
tail. In esophagus, trachea, lung, stomach, hindgut, and the future urinary
bladder, we observed various mesoderm-derived beta1-negative cells (e.g.
fibroblasts, chondrocytes, endothelial cells, and smooth muscle cells) but no
beta1-negative epithelial cells. Since the epithelia of lung, esophagus, trachea,
stomach, hindgut, and urinary bladder are derived from the endodermal gut tube,
we hypothesize that beta1 is essential for the development and/or survival of the
epithelia of the fore- and hindgut and its derivatives.
 
PMID: 14648219 [PubMed - indexed for MEDLINE]
 
 
32. Development. 2003 Dec;130(25):6361-74.
 
Ablation of specific expression domains reveals discrete functions of ectoderm-
and endoderm-derived FGF8 during cardiovascular and pharyngeal development.
 
Macatee TL, Hammond BP, Arenkiel BR, Francis L, Frank DU, Moon AM.
 
Program in Human Molecular Biology and Genetics, University of Utah School of
Medicine, Salt Lake City, UT 84112, USA.
 
Fibroblast growth factor 8 (Fgf8) is expressed in many domains of the developing
embryo. Globally decreased FGF8 signaling during murine embryogenesis results in
a hypomorphic phenotype with a constellation of heart, outflow tract, great
vessel and pharyngeal gland defects that phenocopies human deletion 22q11
syndromes, such as DiGeorge. We postulate that these Fgf8 hypomorphic phenotypes
result from disruption of local FGF8 signaling from pharyngeal arch epithelia to
mesenchymal cells populating and migrating through the third and fourth
pharyngeal arches. To test our hypothesis, and to determine whether the
pharyngeal ectoderm and endoderm Fgf8 expression domains have discrete functional
roles, we performed conditional mutagenesis of Fgf8 using novel Crerecombinase
drivers to achieve domain-specific ablation of Fgf8 gene function in the
pharyngeal arch ectoderm and endoderm. Remarkably, ablating FGF8 protein in the
pharyngeal arch ectoderm causes failure of formation of the fourth pharyngeal
arch artery that results in aortic arch and subclavian artery anomalies in 95% of
mutants; these defects recapitulate the spectrum and frequency of vascular
defects reported in Fgf8 hypomorphs. Surprisingly, no cardiac, outflow tract or
glandular defects were found in ectodermal-domain mutants, indicating that
ectodermally derived FGF8 has essential roles during pharyngeal arch vascular
development distinct from those in cardiac, outflow tract and pharyngeal gland
morphogenesis. By contrast, ablation of FGF8 in the third and fourth pharyngeal
endoderm and ectoderm caused glandular defects and bicuspid aortic valve, which
indicates that the FGF8 endodermal domain has discrete roles in pharyngeal and
valvar development. These results support our hypotheses that local FGF8
signaling from the pharyngeal epithelia is required for pharyngeal vascular and
glandular development, and that the pharyngeal ectodermal and endodermal domains
of FGF8 have separate functions.
 
PMCID: PMC1876660
PMID: 14623825 [PubMed - indexed for MEDLINE]
 
 
33. Mech Dev. 2003 Oct;120(10):1165-76.
 
Expression and function of a starfish Otx ortholog, AmOtx: a conserved role for
Otx proteins in endoderm development that predates divergence of the
eleutherozoa.
 
Hinman VF, Nguyen AT, Davidson EH.
 
Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
 
The sea urchin orthodenticle (Otx)-related transcription factor is an early
activator of other endomesodermally expressed transcription factors. Its normal
function is required for the development of the archenteron and to lock cells
into endomesodermal fate. To determine if this is a basal Otx function in
echinoderms we have studied the role of an Otx ortholog in a starfish, Asterina
miniata. The patterns of AmOtx expression are found to be similar, in many
details, to those reported for other indirectly developing echinoderms and
hemichordates, suggestive of a conserved function both in endoderm development
and ciliary band formation in these two phyla. When downstream targets of the
AmOtx protein are suppressed using a dominant engrailed repressor strategy,
embryos fail to develop the endodermal component of the archenteron, though
initial phases of mesoderm development proceed normally. The function of Otx
proteins in endodermal development at least predated the evolution of the
free-living echinoderms (Eleutherozoa).
 
PMID: 14568105 [PubMed - indexed for MEDLINE]
 
 
34. Gene Expr Patterns. 2003 Oct;3(5):681-4.
 
The mouse secreted frizzled-related protein 5 gene is expressed in the anterior
visceral endoderm and foregut endoderm during early post-implantation
development.
 
Finley KR, Tennessen J, Shawlot W.
 
Department of Genetics, Cell Biology and Development, University of Minnesota,
Minneapolis, MN 55455, USA.
 
The anterior visceral endoderm (AVE) plays an important role in
anterior-posterior axis formation in the mouse. The AVE functions in part by
expressing secreted factors that antagonize growth factor signaling in the
proximal epiblast. Here we report that the Secreted frizzled-related protein 5
(Sfrp5) gene, which encodes a secreted factor that can antagonize Wnt signaling,
is expressed in the AVE and foregut endoderm during early mouse development. At
embryonic day (E) 5.5, Sfrp5 is expressed in the visceral endoderm at the distal
tip region of the embryo and at E6.5 in the AVE opposite the primitive streak. In
Lim1 embryos, which lack anterior neural tissue and sometimes form a secondary
body axis, Sfrp5-expressing cells fail to move towards the anterior and remain at
the distal tip of E6.5 embryos. When compared with Dkk1, which encodes another
secreted Wnt antagonist molecule present in the visceral endoderm, Sfrp5 and Dkk1
expression overlap but Sfrp5 is expressed more broadly in the AVE. Between E7.5
and 8, Sfrp5 is expressed in the foregut endoderm underlying the cardiac
mesoderm. At E8.5, Sfrp5 is expressed in the ventral foregut endoderm that gives
rise to the liver. Additional domains of Sfrp5 expression occur in the dorsal
neural tube and in the forebrain anterior to the optic placode. These findings
identify a gene encoding a secreted Wnt antagonist that is expressed in the
extraembryonic visceral endoderm and anterior definitive endoderm during axis
formation and organogenesis in the mouse.
 
PMID: 12972006 [PubMed - indexed for MEDLINE]
 
 
35. Curr Opin Genet Dev. 2003 Aug;13(4):393-400.
 
Early endoderm development in vertebrates: lineage differentiation and
morphogenetic function.
 
Tam PP, Kanai-Azuma M, Kanai Y.
 
Embryology Unit, Children's Medical Research Institute, Locked Bag 23,
Wentworthville, New South Wales 2145, Australia. ptam@cmri.usyd.edu.au
 
Gastrulation of the vertebrate embryo culminates in the formation of three
primary germ layers: ectoderm, mesoderm and endoderm. The endoderm contributes to
the lining of the gut and the associated organs. New components of the molecular
pathway for endoderm specification have been identified in the zebrafish and
Xenopus. In the mouse, the activity of orthologous factors is involved with the
allocation and differentiation of the definitive endoderm. Morphogenetic
interactions between the endoderm and the other germ layer derivatives are
critical for the morphogenesis of head structures and organogenesis of gut
derivatives.
 
PMID: 12888013 [PubMed - indexed for MEDLINE]
 
 
36. Genesis. 2003 May;36(1):40-7.
 
Paracrine action of FGF4 during periimplantation development maintains
trophectoderm and primitive endoderm.
 
Goldin SN, Papaioannou VE.
 
FGF4, a member of the fibroblast growth factor (FGF) family, is absolutely
required for periimplantation mouse development, although its precise role at
this stage remains unknown. The nature of the defect leading to postimplantation
lethality of embryos lacking zygotic FGF4 is unclear and little is known about
downstream targets of FGF4-initiated signaling within the various cellular
compartments of the blastocyst. Here we report that postimplantation lethality of
Fgf4(-/-) embryos is unlikely to reflect strictly mitogenic requirements for
FGF4. Rather, our results suggest that FGF4 is required to maintain trophectoderm
and primitive endoderm identity at embryonic day 4.5. This result is consistent
with the reported in vitro activity of FGF4 in maintaining trophoblast stem cells
and with the requirement for receptor tyrosine kinase signaling in primitive
endoderm formation. Thus, postimplantation lethality of Fgf4(-/-) embryos likely
results from the failure of proper differentiation and function of extraembryonic
cell types. Copyright 2003 Wiley-Liss, Inc.
 
PMID: 12748966 [PubMed - indexed for MEDLINE]
 
 
37. Gene Expr Patterns. 2003 May;3(2):147-52.
 
Darmin is a novel secreted protein expressed during endoderm development in
Darmin is a novel secreted protein expressed during endoderm development in
Xenopus.
Xenopus. Gene Expr Patterns. 2003 May;3(2):147-52. PubMed PMID: 12711541.
 
Pera EM, Martinez SL, Flanagan JJ, Brechner M, Wessely O, De Robertis EM.
 
Howard Hughes Medical Institute and Department of Biological Chemistry,
University of California, Los Angeles, CA 90095-1662, USA.
 
Endoderm development is an area of intense interest in developmental biology, but
progress has been hampered by the lack of specific markers for differentiated
endodermal cells. In an unbiased secretion cloning screen of Xenopus gastrula
embryos we isolated a novel gene, designated Darmin. Darmin encodes a secreted
protein of 56 kDa containing a peptidase M20 domain characteristic of the
glutamate carboxypeptidase group of zinc metalloproteases. We also identified
homologous Darmin genes in other eukaryotes and in prokaryotes suggesting that
Darmin is the founding member of a family of evolutionarily conserved proteins.
Xenopus Darmin showed zygotic expression in the early endoderm and later became
restricted to the midgut. By secretion cloning of Xenopus cleavage-stage embryos
we isolated another novel protein, designated Darmin-related (Darmin-r) due to
its sequence similarity with Darmin. Darmin-r was maternally expressed and showed
at later stages expression in the lens and pronephric glomus. The
endoderm-specific expression of Darmin makes this gene a useful marker for the
study of endoderm development.
 
PMID: 12711541 [PubMed - indexed for MEDLINE]
 
 
38. Mech Dev. 2003 Mar;120(3):337-48.
 
Redundant early and overlapping larval roles of Xsox17 subgroup genes in Xenopus
endoderm development.
 
Clements D, Cameleyre I, Woodland HR.
 
Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK.
 
We have used antisense morpholino oligos to establish the developmental roles of
three Xsox17 proteins in Xenopus development (Xsox17alpha(1), alpha(2) and beta).
We show that their synthesis can be inhibited with modest amounts of oligo. The
inhibition of each individually produces defects in late midgut development. Loss
of activity of the Xsox17alpha proteins additionally inhibits hindgut formation,
and inhibiting Xsox17alpha(1) disrupts foregut development with variable
penetrance. When all Xsox17 activity is inhibited cell movements are halted
during late gastrulation and the transcription of several endodermally expressed
genes is reduced. Thus the Xsox17 proteins have redundant roles in early
development of the endoderm and partly distinct roles during later organogenesis.
 
PMID: 12591603 [PubMed - indexed for MEDLINE]
 
 
39. Mech Dev. 2003 Jan;120(1):5-18.
 
From endoderm formation to liver and pancreas development in zebrafish.
 
Ober EA, Field HA, Stainier DY.
 
Department of Biochemistry and Biophysics, Programs in Developmental Biology,
Genetics and Human Genetics, University of California, San Francisco, CA
94143-0448, USA.
 
Recent studies in zebrafish have contributed to our understanding of early
endoderm formation in vertebrates. Specifically, they have illustrated the
importance of Nodal signaling as well as three transcription factors,
Faust/Gata5, Bonnie and Clyde, and Casanova, in this process. Ongoing genetic and
embryological studies in zebrafish are also contributing to our understanding of
later aspects of endoderm development, including the formation of the gut and its
associated organs, the liver and pancreas. The generation of transgenic lines
expressing GFP in these organs promises to be particularly helpful in such
studies.
 
PMID: 12490292 [PubMed - indexed for MEDLINE]
 
 
40. Dev Biol. 2002 Sep 15;249(2):191-203.
 
Molecular regulation of vertebrate early endoderm development.
 
Shivdasani RA.
 
Department of Adult Oncology and Cancer Biology, Dana-Faber Cancer Institute,
Boston, MA 02115, USA. ramesh_shivdasani@dcfi.harvard.edu
 
Detailed study of the ectoderm and mesoderm has led to increasingly refined
understanding of molecular mechanisms that operate early in development to
generate cellular diversity. More recently, a number of powerful studies have
begun to characterize the molecular determinants of the endoderm, a germ layer
previously neglected in developmental biology. Work in diverse model systems has
converged on an integrated transcriptional and signaling pathway that serves to
establish the vertebrate endoderm. A T-box transcription factor identified in
Xenopus embryos, VegT, appears to function near the top of an endoderm-specifying
transcriptional hierarchy. VegT activates and reinforces Nodal-related TGFbeta
signaling and also induces expression of essential downstream transcriptional
regulators, Mix-like paired-homeodomain and GATA factors. These proteins
cooperate to regulate expression of a relay of HMG-box Sox-family transcription
factors culminating with Sox 17, which may be an obligate mediator of vertebrate
endoderm development. This review synthesizes findings in three vertebrate model
organisms and discusses these genetic interactions in the context of the
progressive acquisition of endodermal identity early in vertebrate development.
 
PMID: 12221001 [PubMed - indexed for MEDLINE]
 
 
41. Dev Dyn. 2002 Aug;224(4):450-6.
 
Distribution of the titf2/foxe1 gene product is consistent with an important role
in the development of foregut endoderm, palate, and hair.
 
Dathan N, Parlato R, Rosica A, De Felice M, Di Lauro R.
 
Centro di Studi di Biocristallografia del CNR, via Mezzocannone, Naples, Italy.
 
Titf2/foxe1 is a forkhead domain-containing gene expressed in the foregut, in the
thyroid, and in the cranial ectoderm of the developing mouse. Titf2 null mice
exhibit cleft palate and either a sublingual or completely absent thyroid gland.
In humans, mutations of the gene encoding for thyroid transcription factor-2
(TTF-2) result in the Bamforth syndrome, characterized by thyroid agenesis, cleft
palate, spiky hair, and choanal atresia. Here, we report a detailed expression
pattern of TTF-2 protein during mouse embryogenesis and show its presence in
structures where it has not been described yet. At embryonic day (E) 10.5, TTF-2
is expressed in Rathke's pouch, in thyroid, and in the epithelium of the
pharyngeal wall and arches, whereas it is absent in the epithelium of the
pharyngeal pouches. According to this expression, at E13.5, TTF-2 is present in
endoderm derivatives, such as tongue, palate, epiglottis, pharynx, and
oesophagus. Later in embryogenesis, we detect TTF-2 in the choanae and whiskers.
This pattern of expression helps to define the complex phenotype displayed by
human patients. Finally, we show that TTF-2 is a phosphorylated protein. These
results help to characterize the domains of TTF-2 expression, from early
embryogenesis throughout organogenesis, providing more detail on the potential
role of TTF-2 in the development of endoderm and ectoderm derived structures.
Copyright 2002 Wiley-Liss, Inc.
 
PMID: 12203737 [PubMed - indexed for MEDLINE]
 
 
42. Development. 2002 Feb;129(3):551-61.
 
Tail gut endoderm and gut/genitourinary/tail development: a new tissue-specific
role for Hoxa13.
 
de Santa Barbara P, Roberts DJ.
 
Department of Pathology, Massachusetts General Hospital, Harvard Medical School,
Boston, MA 02114, USA.
 
Hoxa13 is expressed early in the caudal mesoderm and endoderm of the developing
hindgut. The tissue-specific roles of Hoxa13 function have not been described.
Hand-foot-genital syndrome, a rare dominantly inherited human malformation
syndrome characterized by distal extremity and genitourinary anomalies, is caused
by mutations in the HOXA13 gene. We show evidence that one specific HOXA13
mutation likely acts as a dominant negative in vivo. When chick HFGa13 is
overexpressed in the chick caudal endoderm early in development, caudal
structural malformations occur. The phenotype is specific to HFGa13 expression in
the posterior endoderm, and includes taillessness and severe gut/genitourinary
(GGU) malformations. Finally, we show that chick HFGa13 negatively regulates
expression of Hoxd13 and antagonizes functions of both endogenous Hoxa13 and
Hoxd13 proteins. We suggest a fundamental role for epithelial specific expression
of Hoxa13 in the epithelial-mesenchymal interaction necessary for tail growth and
posterior GGU patterning.
 
PMCID: PMC2435615
PMID: 11830557 [PubMed - indexed for MEDLINE]
 
 
43. Dev Dyn. 2002 Jan;223(1):33-47.


Pre-gut endoderm of chick embryos is regionalized by 1.5 days of development.


Matsushita S, Ishii Y, Scotting PJ, Kuroiwa A, Yasugi S.
38: Clements D, Cameleyre I, Woodland HR. Redundant early and overlapping larval
roles of Xsox17 subgroup genes in Xenopus endoderm development. Mech Dev. 2003
Mar;120(3):337-48. PubMed PMID: 12591603.


Department of Biology, School of Medicine, Tokyo Women's Medical University,
Shinjuku-ku, Tokyo, Japan. matsus@research.twmu.ac.jp


In this study, we set out to test the ability of endoderm from 1.5-day-old chick
39: Ober EA, Field HA, Stainier DY. From endoderm formation to liver and pancreas
embryos (just before digestive tube formation) to develop region-specific
development in zebrafish. Mech Dev. 2003 Jan;120(1):5-18. Review. PubMed PMID:
characteristics when cultured heterotopically. Various parts of the 1.5-day
12490292.
endoderm were cultured in combination with the flank somatic mesoderm of 3- to
3.5-day chick embryos, and these cultures were analyzed for the expression of
several transcription factors and the differentiation of the endoderm. By 1.5
days of normal development, the transcription factors, which are expressed in
specific digestive organs, cSox2, CdxA, and cHoxb9/a13 were already expressed in
the endodermal cells of the presumptive areas of their later expression domains.
When 1.5-day pre-gut endoderm was cultured for 14-15 days, it showed specific
differentiation into appropriate organ structures. In general, the more anterior
part of the pre-gut endoderm formed the more rostral digestive organ structures
while the posterior part became the caudal gut. The differentiation of these
regions of endoderm matches their normal fate as recently elucidated (Matsushita
[1996a] Rouxs Arch. Dev. Biol. 205:225-231; Matsushita [1999] Dev. Growth Differ.
41:313-319). Expression of cSox2, CdxA, and cHoxb9/a13 in endoderm cultured for
4-5 days is also consistent with their normal fate. Thus, each part of the
pre-gut endoderm appears to be already regionally committed to some extent, in
accordance with its fate by 1.5 days of development. Copyright 2001 Wiley-Liss,
Inc.


PMID: 11803568 [PubMed - indexed for MEDLINE]


40: Shivdasani RA. Molecular regulation of vertebrate early endoderm development.
Dev Biol. 2002 Sep 15;249(2):191-203. Review. PubMed PMID: 12221001.


44. Science. 2001 Oct 19;294(5542):530-1. Epub 2001 Sep 27.


Development. Endothelium--chicken soup for the endoderm.
41: Dathan N, Parlato R, Rosica A, De Felice M, Di Lauro R. Distribution of the
titf2/foxe1 gene product is consistent with an important role in the development
of foregut endoderm, palate, and hair. Dev Dyn. 2002 Aug;224(4):450-6. PubMed
PMID: 12203737.


Bahary N, Zon LI.


Department of Adult Oncology, Dana-Farber Cancer Institute, Boston, MA 02115,
42: de Santa Barbara P, Roberts DJ. Tail gut endoderm and gut/genitourinary/tail
USA.
development: a new tissue-specific role for Hoxa13. Development. 2002
Feb;129(3):551-61. PubMed PMID: 11830557; PubMed Central PMCID: PMC2435615.


Comment on:
    Science. 2001 Oct 19;294(5542):559-63.
    Science. 2001 Oct 19;294(5542):564-7.


Endothelial cells in blood vessels are known to be important during the later
43: Matsushita S, Ishii Y, Scotting PJ, Kuroiwa A, Yasugi S. Pre-gut endoderm of
stages of organ development in the embryo. However, their involvement at the
chick embryos is regionalized by 1.5 days of development. Dev Dyn. 2002
induction stage of organ formation has not been previously documented. As Bahary
Jan;223(1):33-47. PubMed PMID: 11803568.
and Zon explain in their Perspective, new work demonstrates that endothelial
cells secrete factors early in development that induce embryonic endoderm to
become liver or pancreas (Matsumoto et al., Lammert et al.).


PMID: 11577202 [PubMed - indexed for MEDLINE]


44: Bahary N, Zon LI. Development. Endothelium--chicken soup for the endoderm.
Science. 2001 Oct 19;294(5542):530-1. Epub 2001 Sep 27. PubMed PMID: 11577202.


45. EMBO J. 2001 Mar 1;20(5):1114-22.


The transcription factors MTF-1 and USF1 cooperate to regulate mouse
45: Andrews GK, Lee DK, Ravindra R, Lichtlen P, Sirito M, Sawadogo M, Schaffner
W. The transcription factors MTF-1 and USF1 cooperate to regulate mouse
metallothionein-I expression in response to the essential metal zinc in visceral  
metallothionein-I expression in response to the essential metal zinc in visceral  
endoderm cells during early development.
endoderm cells during early development. EMBO J. 2001 Mar 1;20(5):1114-22. PubMed
 
PMID: 11230134; PubMed Central PMCID: PMC145491.
Andrews GK, Lee DK, Ravindra R, Lichtlen P, Sirito M, Sawadogo M, Schaffner W.
 
Department of Biochemistry and Molecular Biology, University of Kansas Medical
Center, 3901 Rainbow Boulevard, Kansas City, KS 66160-7421, USA.
gandrews@kumc.edu
 
During early development of the mouse embryo, expression of the metallothionein-I
(MT-I) gene is heightened specifically in the endoderm cells of the visceral yolk
sac. The mechanisms of regulation of this cell-specific pattern of expression of
metallothionein-I are unknown. However, it has recently been shown that MTF-1,
functioning as a metalloregulatory transcription factor, activates
metallothionein genes in response to the essential metal zinc. In contrast with
the metallothionein genes, MTF-1 is essential for development; null mutant
embryos die due to liver degeneration. We report here that MTF-1 is absolutely
essential for upregulation of MT-I gene expression in visceral endoderm cells and
that optimal expression also involves interactions of the basic helix-loop-helix
upstream stimulatory factor-1 (USF1) with an E-box1-containing sequence at -223
bp in the MT-I promoter. Expression of MT-I in visceral endoderm cells was
dependent on maternal dietary zinc. Thus, the essential metal, zinc, apparently
provides the signaling ligand that activates cell-specific MT-I expression in
visceral endoderm cells.
 
PMCID: PMC145491
PMID: 11230134 [PubMed - indexed for MEDLINE]
 
 
46. Zygote. 2000;8 Suppl 1:S35-6.
 
Gene expression in the endoderm during sea urchin development.
 
Livingston B, David ES, Thurm C.
 
School of Biological Sciences, University of Missouri-Kansas City, 64110, USA.
 
PMID: 11191300 [PubMed - indexed for MEDLINE]
 
 
47. Dev Biol. 2000 Sep 15;225(2):304-21.
 
Visceral endoderm mediates forebrain development by suppressing posteriorizing
signals.
 
Kimura C, Yoshinaga K, Tian E, Suzuki M, Aizawa S, Matsuo I.
 
Department of Morphogenesis, Institute of Molecular Embryology and Genetics,
Kumamoto University, Honjo 2-2-1, Kumamoto, 860-0811, Japan.
 
The anterior visceral endoderm (AVE) has attracted recent attention as a critical
player in mouse forebrain development and has been proposed to act as "head
organizer" in mammals. However, the precise role of the AVE in induction and
patterning of the anterior neuroectoderm is not yet known. Here we identified a
5'-flanking region of the mouse Otx2 gene (VEcis) that governs the transgene
expression in the visceral endoderm. In transgenic embryos, VEcis-active cells
were found in the distal visceral endoderm at 5.5 days postcoitus (dpc), had
begun to move anteriorly at 5.75 dpc, and then became restricted to the AVE prior
to gastrulation. The VEcis-active visceral endoderm cells exhibited ectodermal
morphology distinct from that of the other endoderm cells and consisted of two
cell layers at 5.75 dpc. In the Otx2(-/-) background, the VEcis-active endoderm
cells remained distal even at 6.5 dpc when a primitive streak was formed;
anterior definitive endoderm was not formed nor were any markers of anterior
neuroectoderm ever induced. The Otx2 cDNA transgene under the control of the
VEcis restored these Otx2(-/-) defects, demonstrating that Otx2 is essential to
the anterior movement of distal visceral endoderm cells. In germ-layer explant
assays between ectoderm and visceral endoderm, the AVE did not induce anterior
neuroectoderm markers, but instead suppressed posterior markers in the ectoderm;
Otx2(-/-) visceral endoderm lacked this activity. Thus Otx2 is also essential for
the AVE to repress the posterior character. These results suggest that distal
visceral endoderm cells move to the future anterior side to generate a
prospective forebrain territory indirectly, by preventing posteriorizing signals.
Copyright 2000 Academic Press.
 
PMID: 10985852 [PubMed - indexed for MEDLINE]
 
 
48. Dev Dyn. 2000 Sep;219(1):84-9.


Hex expression suggests a role in the development and function of organs derived
from foregut endoderm.


Bogue CW, Ganea GR, Sturm E, Ianucci R, Jacobs HC.
46: Livingston B, David ES, Thurm C. Gene expression in the endoderm during sea
urchin development. Zygote. 2000;8 Suppl 1:S35-6. Review. PubMed PMID: 11191300.


Department of Pediatrics, Yale University School of Medicine, New Haven,
Connecticut 06520-8064, USA. clifford.bogue@yale.edu


Hex is a divergent homeobox gene expressed as early as E4.5 in the mouse and in a
47: Kimura C, Yoshinaga K, Tian E, Suzuki M, Aizawa S, Matsuo I. Visceral
pattern that suggests a role in anterior-posterior patterning. Later in
endoderm mediates forebrain development by suppressing posteriorizing signals.
embryogenesis, Hex is expressed in the developing thyroid, lung, and liver. We
Dev Biol. 2000 Sep 15;225(2):304-21. PubMed PMID: 10985852.
now show Hex expression during thymus, gallbladder, and pancreas development and
in the adult thyroid, lung, and liver. At E10.0, Hex is expressed in the 3rd
pharyngeal pouch, from which the thymus originates, the endodermal cells of liver
that are invading the septum transversum, the thyroid, the dorsal pancreatic bud,
and gallbladder primoridum. At E13.5, expression is maintained at high levels in
the thyroid, liver, epithelial cells lining the pancreatic and extrahepatic
biliary ducts and is present in both the epithelial and mesenchymal cells of the
lung. Expression in the thymus at this age is less than in the other organs. In
the E16.5 embryo, expression persists in the thyroid, pancreatic, and bile duct
epithelium, lung, and liver, with thymic expression dropping to barely detectable
levels. By E18.5, expression in the thyroid and bile ducts remains high, whereas
lung expression is markedly decreased. At this age, expression in the pancreas
and thymus is no longer present. Finally, we show the cell types in the adult
thyroid, lung, and liver that express Hex in the mature animal. Our results
provide more detail on the potential role of Hex in the development of several
organs derived from foregut endoderm and in the maintenance of function of
several of these organs in the mature animal. Copyright 2000 Wiley-Liss, Inc.


PMID: 10974674 [PubMed - indexed for MEDLINE]


48: Bogue CW, Ganea GR, Sturm E, Ianucci R, Jacobs HC. Hex expression suggests a
role in the development and function of organs derived from foregut endoderm. Dev
Dyn. 2000 Sep;219(1):84-9. PubMed PMID: 10974674.


49. Development. 2000 Jul;127(13):2795-809.


49: Vesque C, Ellis S, Lee A, Szabo M, Thomas P, Beddington R, Placzek M.
Development of chick axial mesoderm: specification of prechordal mesoderm by
Development of chick axial mesoderm: specification of prechordal mesoderm by
anterior endoderm-derived TGFbeta family signalling.
anterior endoderm-derived TGFbeta family signalling. Development. 2000
 
Jul;127(13):2795-809. PubMed PMID: 10851126.
Vesque C, Ellis S, Lee A, Szabo M, Thomas P, Beddington R, Placzek M.
 
Developmental Genetics Programme, Krebs Institute, Firth Court, Sheffield S10
2TN, UK. m.placzek@sheffield.ac.uk
 
Two populations of axial mesoderm cells can be recognised in the chick embryo,
posterior notochord and anterior prechordal mesoderm. We have examined the
cellular and molecular events that govern the specification of prechordal
mesoderm. We report that notochord and prechordal mesoderm cells are intermingled
and share expression of many markers as they initially extend out of Hensen's
node. In vitro culture studies, together with in vivo grafting experiments,
reveal that early extending axial mesoderm cells are labile and that their
character may be defined subsequently through signals that derive from anterior
endodermal tissues. Anterior endoderm elicits aspects of prechordal mesoderm
identity in extending axial mesoderm by repressing notochord characteristics,
briefly maintaining gsc expression and inducing BMP7 expression. Together these
experiments suggest that, in vivo, signalling by anterior endoderm may determine
the extent of prechordal mesoderm. The transforming growth factor (beta)
(TGFbeta) superfamily members BMP2, BMP4, BMP7 and activin, all of which are
transiently expressed in anterior endoderm mimic distinct aspects of its
patterning actions. Together our results suggest that anterior endoderm-derived
TGFbetas may specify prechordal mesoderm character in chick axial mesoderm.
 
PMID: 10851126 [PubMed - indexed for MEDLINE]
 
 
50. Dev Dyn. 2000 Apr;217(4):327-42.
 
Endoderm and heart development.
 
Lough J, Sugi Y.
 
Department of Cell Biology, Neurobiology, and Anatomy, Medical College of
Wisconsin, Milwaukee, Wisconsin, USA. jlough@mcw.edu
 
Since the first half of the 20th century, experimental embryologists have noted a
relationship between endoderm cells and the development of cardiac tissue from
mesoderm. During the past decade, the accumulation of evidence for an obligatory
interaction between endoderm and mesoderm during the specification and terminal
differentiation of myocardial, and more recently endocardial, cells has markedly
accelerated. Moreover, the endoderm-derived molecules that may regulate these
processes are being identified. It now appears that endoderm-derived growth
factors regulate the formation of both myocardial and endocardial cells during
specification, terminal differentiation, and perhaps morphogenesis of cells in
the developing embryonic heart.
 
PMID: 10767078 [PubMed - indexed for MEDLINE]
 
 
51. Proc Natl Acad Sci U S A. 2000 Apr 11;97(8):4076-81.
 
Action of the Caenorhabditis elegans GATA factor END-1 in Xenopus suggests that
similar mechanisms initiate endoderm development in ecdysozoa and vertebrates.
 
Shoichet SA, Malik TH, Rothman JH, Shivdasani RA.
 
Department of Adult Oncology, Dana-Farber Cancer Institute, 44 Binney Street,
Boston, MA 02115, USA.
 
In ecdysozoan protostomes, including arthropods and nematodes, transcription
factors of the GATA family specify the endoderm: Drosophila dGATAb (ABF/Serpent)
and Caenorhabditis elegans END-1 play important roles in generating this primary
germ layer. end-1 is the earliest expressed endoderm-specific gene known in C.
elegans and appears to initiate the program of gene expression required for
endoderm differentiation, including a cascade of GATA factors required for
development and maintenance of the intestine. Among vertebrate GATA proteins, the
GATA-4/5/6 subfamily regulates aspects of late endoderm development, but a role
for GATA factors in establishing the endoderm is unknown. We show here that END-1
binds to the canonical target DNA sequence WGATAR with specificity similar to
that of vertebrate GATA-1 and GATA-4, and that it functions as a transcriptional
activator. We exploited this activity of END-1 to demonstrate that establishment
of the vertebrate endoderm, like that of invertebrate species, also appears to
involve GATA transcriptional activity. Like the known vertebrate endoderm
regulators Mixer and Sox17, END-1 is a potent activator of endoderm
differentiation in isolated Xenopus ectoderm. Moreover, a dominant inhibitory
GATA-binding fusion protein abrogates endoderm differentiation in intact embryos.
By examining these effects in conjunction with those of Mixer- and
Sox17beta-activating and dominant inhibitory constructs, we further establish the
likely relationships between GATA activity and these regulators in early
development of the vertebrate endoderm. These results suggest that GATA factors
may function sequentially to regulate endoderm differentiation in both
protostomes and deuterostomes.
 
PMCID: PMC18153
PMID: 10760276 [PubMed - indexed for MEDLINE]
 
 
52. Trends Genet. 2000 Mar;16(3):124-30.
 
Endoderm development: from patterning to organogenesis.
 
Grapin-Botton A, Melton DA.
 
Department of Molecular and Cellular Biology, and Howard Hughes Medical
Institute, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA.
grapin@fas.harvard.edu
 
Although the ectoderm and mesoderm have been the focus of intensive work in the
recent era of studies on the molecular control of vertebrate development, the
endoderm has received less attention. Because signaling must occur between germ
layers in order to achieve a properly organized body, our understanding of the
coordinated development of all organs requires a more thorough consideration of
the endoderm and its derivatives. This review focuses on present knowledge and
perspectives concerning endoderm patterning and organogenesis. Some of the
classical embryology of the endoderm is discussed and the progress and
deficiencies in cellular and molecular studies are noted.
 
PMID: 10689353 [PubMed - indexed for MEDLINE]
 
 
53. Int J Dev Biol. 1999;43(7):605-13.
 
Pieter Nieuwkoop's contributions to the understanding of meso-endoderm induction
and neural induction in chordate development.
 
Gerhart J.
 
Department of Molecular and Cell Biology, University of California, Berkeley
94720, USA. gerhart@socrates.berkeley.edu
 
Pieter Nieuwkoop, who died September 18, 1996, at age 79 in Utrecht, The
Netherlands, is remembered by developmental biologists for his numerous research
contributions and integrative hypotheses over the past 50 years, especially in
the areas of neural induction, meso-endoderm induction, and germ cell induction
in chordates. Most of his experimentation was done on the embryos of amphibia,
the preferred vertebrate embryo of the early years of the 20th century. One of
his last publications contains a comparison of the experimental advantages and
disadvantages of anuran and urodele amphibians (Nieuwkoop, 1996). The
significance of his findings and interpretations for developmental biology can be
estimated from the fact that researchers of many laboratories worldwide continue
to work on the phenomena he first described and to extend the hypotheses he first
formulated. The aim of this article is to review Nieuwkoop's main contributions
and to cite the recent extensions by others.
 
PMID: 10668970 [PubMed - indexed for MEDLINE]
 
 
54. Development. 2000 Feb;127(4):869-79.
 
Endoderm patterning by the notochord: development of the hypochord in Xenopus.


Cleaver O, Seufert DW, Krieg PA.


Division of Molecular Cell and Developmental Biology, School of Biological
50: Lough J, Sugi Y. Endoderm and heart development. Dev Dyn. 2000
Sciences, University of Texas at Austin, Austin, TX 78712, USA.
Apr;217(4):327-42. Review. PubMed PMID: 10767078.


The patterning and differentiation of the vertebrate endoderm requires signaling
from adjacent tissues. In this report, we demonstrate that signals from the
notochord are critical for the development of the hypochord, which is a
transient, endodermally derived structure that lies immediately ventral to the
notochord in the amphibian and fish embryo. It appears likely that the hypochord
is required for the formation of the dorsal aorta in these organisms. We show
that removal of the notochord during early neurulation leads to the complete
failure of hypochord development and to the elimination of expression of the
hypochord marker, VEGF. Removal of the notochord during late neurulation,
however, does not interfere with hypochord formation. These results suggest that
signals arising in the notochord instruct cells in the underlying endoderm to
take on a hypochord fate during early neural stages, and that the hypochord does
not depend on further notochord signals for maintenance. In reciprocal
experiments, when the endoderm receives excess notochord signaling, a
significantly enlarged hypochord develops. Overall, these results demonstrate
that, in addition to patterning neural and mesodermal tissues, the notochord
plays an important role in patterning of the endoderm.


PMID: 10648245 [PubMed - indexed for MEDLINE]
51: Shoichet SA, Malik TH, Rothman JH, Shivdasani RA. Action of the
Caenorhabditis elegans GATA factor END-1 in Xenopus suggests that similar
mechanisms initiate endoderm development in ecdysozoa and vertebrates. Proc Natl
Acad Sci U S A. 2000 Apr 11;97(8):4076-81. PubMed PMID: 10760276; PubMed Central
PMCID: PMC18153.




55. Annu Rev Cell Dev Biol. 1999;15:393-410.
52: Grapin-Botton A, Melton DA. Endoderm development: from patterning to
organogenesis. Trends Genet. 2000 Mar;16(3):124-30. Review. PubMed PMID:
10689353.


Vertebrate endoderm development.


Wells JM, Melton DA.
53: Gerhart J. Pieter Nieuwkoop's contributions to the understanding of
meso-endoderm induction and neural induction in chordate development. Int J Dev
Biol. 1999;43(7):605-13. PubMed PMID: 10668970.


Department of Molecular and Cellular Biology, Harvard University, Cambridge,
Massachusetts 02138, USA. wells@biohp.harvard.edu


Endoderm, one of the three principal germ layers, contributes to all organs of
54: Cleaver O, Seufert DW, Krieg PA. Endoderm patterning by the notochord:
the alimentary tract. For simplicity, this review divides formation of endodermal
development of the hypochord in Xenopus. Development. 2000 Feb;127(4):869-79.
organs into four fundamental steps: (a) formation of endoderm during
PubMed PMID: 10648245.
gastrulation, (b) morphogenesis of a gut tube from a sheet of cells, (c) budding
of organ domains from the tube, and (d) differentiation of organ-specific cell
types within the growing buds. We discuss possible mechanisms that regulate how
undifferentiated endoderm becomes specified into a myriad of cell types that
populate the respiratory and gastrointestinal tracts.


PMID: 10611967 [PubMed - indexed for MEDLINE]


55: Wells JM, Melton DA. Vertebrate endoderm development. Annu Rev Cell Dev Biol.
1999;15:393-410. Review. PubMed PMID: 10611967.


56. Genes Dev. 1999 Nov 15;13(22):2983-95.


56: Reiter JF, Alexander J, Rodaway A, Yelon D, Patient R, Holder N, Stainier DY.
Gata5 is required for the development of the heart and endoderm in zebrafish.
Gata5 is required for the development of the heart and endoderm in zebrafish.
Genes Dev. 1999 Nov 15;13(22):2983-95. PubMed PMID: 10580005; PubMed Central
PMCID: PMC317161.


Reiter JF, Alexander J, Rodaway A, Yelon D, Patient R, Holder N, Stainier DY.
Department of Biochemistry and Biophysics, Programs in Human Genetics and
Developmental Biology, University of California at San Francisco, San Francisco,
California 94143-0448 USA.
The mechanisms regulating vertebrate heart and endoderm development have recently
become the focus of intense study. Here we present evidence from both loss- and
gain-of-function experiments that the zinc finger transcription factor Gata5 is
an essential regulator of multiple aspects of heart and endoderm development. We
demonstrate that zebrafish Gata5 is encoded by the faust locus. Analysis of faust
mutants indicates that early in embryogenesis Gata5 is required for the
production of normal numbers of developing myocardial precursors and the
expression of normal levels of several myocardial genes including nkx2.5. Later,
Gata5 is necessary for the elaboration of ventricular tissue. We further
demonstrate that Gata5 is required for the migration of the cardiac primordia to
the embryonic midline and for endodermal morphogenesis. Significantly,
overexpression of gata5 induces the ectopic expression of several myocardial
genes including nkx2.5 and can produce ectopic foci of beating myocardial tissue.
Together, these results implicate zebrafish Gata5 in controlling the growth,
morphogenesis, and differentiation of the heart and endoderm and indicate that
Gata5 regulates the expression of the early myocardial gene nkx2.5.


PMCID: PMC317161
57: Dale L. Vertebrate development: Multiple phases to endoderm formation. Curr
PMID: 10580005 [PubMed - indexed for MEDLINE]
Biol. 1999 Nov 4;9(21):R812-5. PubMed PMID: 10556077.




57. Curr Biol. 1999 Nov 4;9(21):R812-5.
58: Ristoratore F, Spagnuolo A, Aniello F, Branno M, Fabbrini F, Di Lauro R.
 
Vertebrate development: Multiple phases to endoderm formation.
 
Dale L.
 
Department of Anatomy and Developmental Biology, University College London, Gower
Street, London, WC1E 6BT, UK. l.dale@ucl.ac.uk
 
Recent results support a two-step model for endoderm formation in amphibian
embryos, in which endoderm is initially specified by localised maternal factors,  
including the transcription factor VegT, but is then maintained by extracellular
signalling molecules of the transforming growth factor-beta family.
 
PMID: 10556077 [PubMed - indexed for MEDLINE]
 
 
58. Development. 1999 Nov;126(22):5149-59.
 
Expression and functional analysis of Cititf1, an ascidian NK-2 class gene,
Expression and functional analysis of Cititf1, an ascidian NK-2 class gene,
suggest its role in endoderm development.
suggest its role in endoderm development. Development. 1999 Nov;126(22):5149-59.  
 
PubMed PMID: 10529431.
Ristoratore F, Spagnuolo A, Aniello F, Branno M, Fabbrini F, Di Lauro R.
 
Laboratory of Biochemistry and Molecular Biology, Stazione Zoologica Anton Dohrn,
Villa Comunale, Italy.
 
In solitary ascidians the fate of endoderm is determined at a very early stage of
development and depends on cytoplasmic factors whose nature has not been
determined. We have isolated a member of the NK-2 gene family, Cititf1, from the
ascidian Ciona intestinalis, showing high sequence homology to mammalian TITF1.
The Cititf1 gene was expressed in all endodermal precursors at the pregastrula
and gastrula stages, and is thus the first specific regulatory endodermal marker
to be isolated from an ascidian. Cititf1 expression was downregulated at the end
of gastrulation to reappear at middle tailbud and larval stages in the most
anterior and ventral parts of head endoderm, regions which give rise, after
metamorphosis, to the adult endostyle, where Cititf1 mRNA was still present.
Microinjection of Cititf1 mRNA into fertilized eggs resulted in tadpole larvae
with abnormalities in head-trunk development consequent to the formation of
excess endoderm, perhaps due to recruitment of notochord precursors to an
endodermal fate. These data suggest that Cititf1 plays an important role in
normal endoderm differentiation during ascidian embryogenesis.
 
PMID: 10529431 [PubMed - indexed for MEDLINE]
 
 
59. Development. 1999 Oct;126(19):4193-200.
 
Bix4 is activated directly by VegT and mediates endoderm formation in Xenopus
development.
 
Casey ES, Tada M, Fairclough L, Wylie CC, Heasman J, Smith JC.
 
Division of Developmental Biology, National Institute for Medical Research, The
Ridgeway, Mill Hill, London NW7 1AA, UK. jim@nimr.mrc. ac.uk
 
The maternal T-box gene VegT, whose transcripts are restricted to the vegetal
hemisphere of the Xenopus embryo, plays an essential role in early development.
Depletion of maternal VegT transcripts causes embryos to develop with no
endoderm, while vegetal blastomeres lose the ability to induce mesoderm (Zhang,
J., Houston, D. W., King, M. L., Payne, C., Wylie, C. and Heasman, J. (1998) Cell
94, 515-524). The targets of VegT, a transcription activator, must therefore
include genes involved both in the specification of endoderm and in the
production of mesoderm-inducing signals. We recently reported that the upstream
regulatory region of the homeobox-containing gene Bix4 contains T-box binding
sites. Here we show that expression of Bix4 requires maternal VegT and that two
T-box binding sites are necessary and sufficient for mesodermal and endodermal
expression of reporter genes driven by the Bix4 promoter in transgenic Xenopus
embryos. Remarkably, a single T-box binding site is able to act as a
mesoderm-specific enhancer when placed upstream of a minimal promoter. Finally,
we show that Bix4 rescues the formation of endodermal markers in embryos in which
VegT transcripts have been ablated but does not restore the ability of vegetal
pole blastomeres to induce mesoderm. These results demonstrate that Bix4 acts
directly downstream of VegT to specify endodermal differentiation in Xenopus
embryos.
 
PMID: 10477288 [PubMed - indexed for MEDLINE]
 
 
60. Development. 1999 Sep;126(18):4005-15.
 
Bmp signaling regulates proximal-distal differentiation of endoderm in mouse lung
development.
 
Weaver M, Yingling JM, Dunn NR, Bellusci S, Hogan BL.
 
Howard Hughes Medical Institute, Department of Cell Biology, Nashville, TN, USA.
 
In the mature mouse lung, the proximal-distal (P-D) axis is delineated by two
distinct epithelial subpopulations: the proximal bronchiolar epithelium and the
distal respiratory epithelium. Little is known about the signaling molecules that
pattern the lung along the P-D axis. One candidate is Bone Morphogenetic Protein
4 (Bmp4), which is expressed in a dynamic pattern in the epithelial cells in the
tips of growing lung buds. Previous studies in which Bmp4 was overexpressed in
the lung endoderm (Bellusci, S., Henderson, R., Winnier, G., Oikawa, T. and
Hogan, B. L. M. (1996) Development 122, 1693-1702) suggested that this factor
plays an important role in lung morphogenesis. To further investigate this
question, two complementary approaches were utilized to inhibit Bmp signaling in
vivo. The Bmp antagonist Xnoggin and, independently, a dominant negative Bmp
receptor (dnAlk6), were overexpressed using the surfactant protein C (Sp-C)
promoter/enhancer. Inhibiting Bmp signaling results in a severe reduction in
distal epithelial cell types and a concurrent increase in proximal cell types, as
indicated by morphology and expression of marker genes, including the proximally
expressed hepatocyte nuclear factor/forkhead homologue 4 (Hfh4) and Clara cell
marker CC10, and the distal marker Sp-C. In addition, electron microscopy
demonstrates the presence of ciliated cells, a proximal cell type, in the most
peripheral regions of the transgenic lungs. We propose a model in which Bmp4 is a
component of an apical signaling center controlling P-D patterning. Endodermal
cells at the periphery of the lung, which are exposed to high levels of Bmp4,
maintain or adopt a distal character, while cells receiving little or no Bmp4
signal initiate a proximal differentiation program.
 
PMID: 10457010 [PubMed - indexed for MEDLINE]
 
 
61. Int J Dev Biol. 1999 May;43(3):183-205.
 
Distinct roles for visceral endoderm during embryonic mouse development.
 
Bielinska M, Narita N, Wilson DB.
 
Department of Pediatrics, Washington University School of Medicine, St. Louis, MO
63110, USA.
 
The murine visceral endoderm is an extraembryonic cell layer that appears prior
to gastrulation and performs critical functions during embryogenesis. The
traditional role ascribed to the visceral endoderm entails nutrient uptake and
transport. Besides synthesizing a number of specialized proteins that facilitate
uptake, digestion, and secretion of nutrients, the extraembryonic visceral
endoderm coordinates blood cell differentiation and vessel formation in the
adjoining mesoderm, thereby facilitating efficient exchange of nutrients and
gases between the mother and embryo. Recent studies suggest that in addition to
this nutrient exchange function the visceral endoderm overlying the egg cylinder
stage embryo plays an active role in guiding early development. Cells in the
anterior visceral endoderm function as an early organizer. Prior to formation of
the primitive streak, these cells express specific gene products that specify the
fate of underlying embryonic tissues. In this review we highlight recent
investigations demonstrating this dual role for visceral endoderm as a provider
of both nutrients and developmental cues for the early embryo.
 
PMID: 10410899 [PubMed - indexed for MEDLINE]
 
 
62. Science. 1999 Jun 18;284(5422):1998-2003.
 
Initiation of mammalian liver development from endoderm by fibroblast growth
factors.
 
Jung J, Zheng M, Goldfarb M, Zaret KS.
 
Department of Molecular Biology, Cell Biology, and Biochemistry, Brown
University, Box G-J363, Providence, RI 02912, USA.
 
The signaling molecules that elicit embryonic induction of the liver from the
mammalian gut endoderm or induction of other gut-derived organs are unknown.
Close proximity of cardiac mesoderm, which expresses fibroblast growth factors
(FGFs) 1, 2, and 8, causes the foregut endoderm to develop into the liver.
Treatment of isolated foregut endoderm from mouse embryos with FGF1 or FGF2, but
not FGF8, was sufficient to replace cardiac mesoderm as an inducer of the liver
gene expression program, the latter being the first step of hepatogenesis. The
hepatogenic response was restricted to endoderm tissue, which selectively
coexpresses FGF receptors 1 and 4. Further studies with FGFs and their specific
inhibitors showed that FGF8 contributes to the morphogenetic outgrowth of the
hepatic endoderm. Thus, different FGF signals appear to initiate distinct phases
of liver development during mammalian organogenesis.
 
PMID: 10373120 [PubMed - indexed for MEDLINE]
 
 
63. Mech Ageing Dev. 1999 Apr 1;108(1):77-85.
 
Evidence that FGF receptor signaling is necessary for endoderm-regulated
development of precardiac mesoderm.
 
Zhu X, Sasse J, Lough J.
 
Department of Cell Biology, Neurobiology and Anatomy and Cardiovascular Research
Center, Medical College of Wisconsin, Milwaukee 53226, USA.
 
Endoderm cells in the heart forming region (HFR endoderm) of stage 6 chicken
embryos are required to support the proliferation and terminal differentiation of
precardiac mesoderm cells in vitro. The endoderm's effect can be substituted by
growth factors, including members of the fibroblast growth factor (FGF) family.
However, direct implication of FGFs in this process requires evidence that
inhibition of FGF signaling interferes with proliferation and/or terminal
differentiation. This report examines the consequences of treating
endoderm/precardiac mesoderm co-explants with agents that inactivate FGF
receptors. Using sodium chlorate, which prevents FGF ligand-receptor interaction,
it was observed that the percentage of S-phase precardiac mesoderm cells was
markedly reduced, suggesting that cell proliferation was inhibited. To more
specifically affect FGF signaling, the explants were treated with an antibody
that recognizes an extracellular domain of FGF receptor-1 (FGFR-1). This
treatment similarly inhibited cell proliferation. Although both agents modestly
delayed cardiac myocyte differentiation as indicated by the contractile function,
expression of alpha-sarcomeric actin was not affected. These findings provide
additional evidence that an intact FGF signaling pathway is required during heart
development.
 
PMID: 10366041 [PubMed - indexed for MEDLINE]
 
 
64. Mech Dev. 1998 Dec;79(1-2):83-97.
 
Drosophila endoderm development requires a novel homeobox gene which is a target
of Wingless and Dpp signalling.
 
Fuss B, Hoch M.
 
Max-Planck-Institut für biophysikalische Chemie, Abt. Molekulare
Entwicklungsbiologie, Göttingen, Germany.
 
We have identified and cloned a novel type of homeobox gene that is composed of
two homeodomains and is expressed in the Drosophila endoderm. Mutant analysis
reveals that its activity is required at the foregut/midgut boundary for the
development of the proventriculus. This organ regulates food passage from the
foregut into the midgut and forms by the infolding of ectoderm and
endoderm-derived tissues. The endodermal outer wall structure of the
proventriculus is collapsed in the mutants leading to a failure of the ectodermal
part to invaginate and build a functional multilayered organ. Lack-of-function
and gain-of-function experiments show that the expression of this homeobox gene
in the proventriculus endoderm is induced in response to Wingless activity
emanating from the ectoderm/endoderm boundary whereas its expression in the
central midgut is controlled by Dpp and Wingless signalling emanating from the
overlying visceral mesoderm.
 
PMID: 10349623 [PubMed - indexed for MEDLINE]
 
 
65. Development. 1999 Feb;126(4):827-38.
 
Origin and development of the zebrafish endoderm.
 
Warga RM, Nüsslein-Volhard C.
 
Max-Planck-Institut für Entwicklungsbiologie, Abteilung Genetik, Spemannstrasse
35, Germany. rachel_warga@urmc.rochester.edu
 
The segregation of cells into germ layers is one of the earliest events in the
establishment of cell fate in the embryo. In the zebrafish, endoderm and mesoderm
are derived from cells that involute into an internal layer, the hypoblast,
whereas ectoderm is derived from cells that remain in the outer layer, the
epiblast. In this study, we examine the origin of the zebrafish endoderm and its
separation from the mesoderm. By labeling individual cells located at the margin
of the blastula, we demonstrate that all structures that are endodermal in origin
are derived predominantly from the more dorsal and lateral cells of the
blastoderm margin. Frequently marginal cells give rise to both endodermal and
mesodermal derivatives, demonstrating that these two lineages have not yet
separated. Cells located farther than 4 cell diameters from the margin give rise
exclusively to mesoderm, and not to endoderm. Following involution, we see a
variety of cellular changes indicating the differentiation of the two germ
layers. Endodermal cells gradually flatten and extend filopodial processes
forming a noncontiguous inner layer of cells against the yolk. At this time, they
also begin to express Forkhead-domain 2 protein. Mesodermal cells form a coherent
layer of round cells separating the endoderm and ectoderm. In cyclops-mutant
embryos that have reduced mesodermal anlage, we demonstrate that by late
gastrulation not only mesodermal but also endodermal cells are fewer in number.
This suggests that a common pathway initially specifies germ layers together
before a progressive sequence of determinative events segregate endoderm and
mesoderm into morphologically distinct germ layers.
 
PMID: 9895329 [PubMed - indexed for MEDLINE]
 
 
66. Science. 1998 Jul 3;281(5373):91-6.
 
Mixer, a homeobox gene required for endoderm development.
 
Henry GL, Melton DA.
 
Howard Hughes Medical Institute, Department of Molecular and Cellular Biology,
Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA.
 
An expression cloning strategy in Xenopus laevis was used to isolate a
homeobox-containing gene, Mixer, that can cause embryonic cells to form endoderm.
Mixer transcripts are found specifically in the prospective endoderm of gastrula,
which coincides with the time and place that endodermal cells become
histologically distinct and irreversibly determined. Loss-of-function studies
with a dominant inhibitory mutant demonstrate that Mixer activity is required for
endoderm development. In particular, the expression of Sox17alpha and Sox17beta,
two previously identified endodermal determinants, require Mixer function.
Together, these data suggest that Mixer is an embryonic transcription factor
involved in specifying the endodermal germ layer.
 
PMID: 9651252 [PubMed - indexed for MEDLINE]
 
 
67. Development. 1997 Nov;124(21):4243-52.
 
Notochord to endoderm signaling is required for pancreas development.
 
Kim SK, Hebrok M, Melton DA.
 
Department of Molecular and Cellular Biology, and Howard Hughes Medical
Institute, Harvard University, Cambridge, Massachusetts 02138, USA.
 
The role of the notochord in inducing and patterning adjacent neural and
mesodermal tissues is well established. We provide evidence that the notochord is
also required for one of the earliest known steps in the development of the
pancreas, an endodermally derived organ. At a developmental stage in chick
embryos when the notochord touches the endoderm, removal of notochord eliminates
subsequent expression of several markers of dorsal pancreas bud development,
including insulin, glucagon and carboxypeptidase A. Pancreatic gene expression
can be initiated and maintained in prepancreatic chick endoderm grown in vitro
with notochord. Non-pancreatic endoderm, however, does not express pancreatic
genes when recombined with the same notochord. The results suggest that the
notochord provides a permissive signal to endoderm to specify pancreatic fate in
a stepwise manner.
 
PMID: 9334273 [PubMed - indexed for MEDLINE]
 
 
68. EMBO J. 1997 Jul 1;16(13):3995-4006.
 
Transcriptional regulation in endoderm development: characterization of an
enhancer controlling Hnf3g expression by transgenesis and targeted mutagenesis.
 
Hiemisch H, Schütz G, Kaestner KH.
 
Molecular Biology of the Cell I Division, German Cancer Research Center,
Heidelberg.
 
The hepatic nuclear factor 3gamma (Hnf3g) is a member of the winged helix gene
family of transcription factors and is thought to be involved in
anterior-posterior regionalization of the primitive gut. In this study,
cis-regulatory elements essential for the expression of Hnf3g in vivo have been
characterized. To this end, a 170 kb yeast artificial chromosome (YAC) carrying
the entire Hnf3g locus was isolated and modified with a lacZ reporter gene. The
two mouse lines carrying the unfragmented Hnf3g-lacZ YAC showed tissue-specific,
copy number-dependent and position-independent expression, proving that 170 kb of
the Hnf3g locus contain all elements important in the regulation of Hnf3g.
Cis-regulatory elements necessary for expression of Hnf3g were identified in a
three-step procedure. First, DNase I hypersensitive site mapping was used to
delineate important chromatin regions around the gene required for
tissue-specific activation of Hnf3g. Second, plasmid-derived transgenes and gene
targeting of the endogenous Hnf3g gene locus were used to demonstrate that the
3'-flanking region of the gene is necessary and sufficient to direct reporter
gene expression in liver, pancreas, stomach and small intestine. Third, a binding
site for HNF-1alpha and beta, factors expressed in organs derived from the
endoderm such as liver, gut and pancreas, was identified in this 3'-enhancer and
shown to be crucial for enhancer function in vitro. Based on its expression
pattern we inferred that HNF-1beta is a likely candidate for directly activating
Hnf3g gene expression during development.
 
PMCID: PMC1170023
PMID: 9233809 [PubMed - indexed for MEDLINE]
 
 
69. Dev Growth Differ. 1997 Apr;39(2):199-205.
 
Analysis of the temporal expression of endoderm-specific alkaline phosphatase
during development of the ascidian Halocynthia roretzi.
 
Nishida H, Kumano G.
 
Department of Life Sciences, Tokyo Institute of Technology, Midori-ku, Yokohama,
Japan.
 
During embryogenesis of ascidians, endoderm cells initiate certain processes
associated with differentiation and produce a tissue-specific enzyme, alkaline
phosphatase (ALP). ALP has been used as a histochemical marker of endoderm
differentiation. In the present study, the temporal profile of ALP expression
during embryogenesis was investigated. In Halocynthia roretzi, endoderm-specific
ALP is a membrane bound protein and is distinguishable from maternal cytoplasmic
ALP by molecular mass. The activity of endodermal ALP first appeared at the early
tail-bud stage. Treatment of developing embryos with inhibitors of translation
and transcription was started at various stages. The results suggested that the
synthesis of endodermal ALP protein started at the early tail-bud stage, and that
the transcription of mRNA was initiated in the gastrula. In other ascidians,
Ciona and Styela, it has been suggested that a significant amount of maternal ALP
mRNA exists in eggs. The present study revealed that there are significant
species differences in ALP expression during ascidian embryogenesis.
 
PMID: 9108333 [PubMed - indexed for MEDLINE]
 
 
70. Development. 1996 Dec;122(12):4023-31.
 
A molecular aspect of hematopoiesis and endoderm development common to
vertebrates and Drosophila.
 
Rehorn KP, Thelen H, Michelson AM, Reuter R.
 
Institut für Genetik, Universität zu Köln, Germany.
 
In vertebrates, transcriptional regulators of the GATA family appear to have a
conserved function in differentiation and organ development. GATA-1, -2 and -3
are required for different aspects of hematopoiesis, while GATA-4, -5 and -6 are
expressed in various organs of endodermal origin, such as intestine and liver,
and are implicated in endodermal differentiation. Here we report that the
Drosophila gene serpent (srp) encodes the previously described GATA factor ABF.
The multiple functions of srp in Drosophila suggest that it is an ortholog of the
entire vertebrate Gata family. srp is required for the differentiation and
morphogenesis of the endodermal gut. Here we show that it is also essential for
Drosophila hematopoiesis and for the formation of the fat body, the insect organ
analogous to the liver. These findings imply that some aspects of the molecular
mechanisms underlying blood cell development as well as endodermal
differentiation are early acquisitions of metazoan evolution and may be common to
most higher animals.
 
PMID: 9012522 [PubMed - indexed for MEDLINE]
 
 
71. Anat Rec. 1996 Oct;246(2):293-304.
 
Unusual aspects of inner cell mass formation, endoderm differentiation,
Reichert's membrane development, and amniogenesis in the lesser bulldog bat,
Noctilio albiventris.
 
Rasweiler JJ 4th, Badwaik NK.
 
Department of Obstetrics and Gynecology, Cornell University Medical College, New
York, NY 10021, USA.
 
BACKGROUND AND METHODS: The early embryogenesis of the lesser bulldog bat,
Noctilio albiventris (family Noctilionidae), was examined histologically in 59
pregnant females collected from a reproductively synchronized population in
Colombia. RESULTS: Early blastocysts of Noctilio are unusual in lacking a typical
inner cell mass. Instead, cells inside of the trophoblast are dispersed for a
period as a monolayer. A typical inner cell mass (ICM) only forms and becomes
properly oriented after the initiation of implantation. Several features of
Reichert's membrane in this species are also noteworthy: it develops between the
ICM and trophoblast and between the parietal endoderm and trophoblast; it becomes
linked to a meshwork of basal laminalike material that extends into the ICM; and
it appears to be continuous, or fused, with prominent basal laminae that develop
within the cytotrophoblastic villi that radiate throughout the preplacenta.
Amniogenesis occurs by cavitation and converts the ICM into a hollow epiblastic
vesicle. Gastrulation commences before this vesicle exhibits obvious
differentiation into an embryonic shield and amniotic ectoderm. CONCLUSIONS:
Because development and proper orientation of a typical ICM in Noctilio occur
after the initiation of implantation, these may involve the migration of cells on
the interior of the blastocyst and/or an unusual method of early endoderm
differentiation. The possibility exists that epiblast, endoderm, and
cytotrophoblast may all contribute to the secretion of Reichert's membrane in
this bat. Although the early embryogenesis of Noctilio exhibits many similarities
to that in phyllostomid bats, substantial differences also exist between these
closely related species.
 
PMID: 8888970 [PubMed - indexed for MEDLINE]
 
 
72. J Cell Biol. 1994 Jul;126(1):211-21.
 
Fetal endoderm primarily holds the temporal and positional information required
for mammalian intestinal development.
 
Duluc I, Freund JN, Leberquier C, Kedinger M.
 
INSERM U381, Strasbourg, France.
 
In rodents, the intestinal tract progressively acquires a functional
regionalization during postnatal development. Using lactase-phlorizin hydrolase
as a marker, we have analyzed in a xenograft model the ontogenic potencies of
fetal rat intestinal segments taken prior to endoderm cytodifferentiation.
Segments from the presumptive proximal jejunum and distal ileum grafted in nude
mice developed correct spatial and temporal patterns of lactase protein and mRNA
expression, which reproduced the normal pre- and post-weaning conditions.
Segments from the fetal colon showed a faint lactase immunostaining 8-10 d after
transplantation in chick embryos but not in mice; it is consistent with the
transient expression of this enzyme in the colon of rat neonates. Heterotopic
cross-associations comprising endoderm and mesenchyme from the presumptive
proximal jejunum and distal ileum developed as xenografts in nude mice, and they
exhibited lactase mRNA and protein expression patterns that were typical of the
origin of the endodermal moiety. Endoderm from the distal ileum also expressed a
normal lactase pattern when it was associated to fetal skin fibroblasts, while
the fibroblasts differentiated into muscle layers containing alpha-smooth-muscle
actin. Noteworthy, associations comprising colon endoderm and small intestinal
mesenchyme showed a typical small intestinal morphology and expressed the
digestive enzyme sucrase-isomaltase normally absent in the colon. However, in
heterologous associations comprising lung or stomach endoderm and small
intestinal mesenchyme, the epithelial compartment expressed markers in accordance
to their tissue of origin but neither intestinal lactase nor sucrase-isomaltase.
A thick intestinal muscle coat in which cells expressed alpha-smooth-muscle actin
surrounded the grafts. The results demonstrate that: (a) the temporal and
positional information needed for intestinal ontogeny up to the post-weaning
stage results from an intrinsic program that is fixed in mammalian fetuses prior
to endoderm cytodifferentiation; (b) this temporal and positional information is
primarily carried by the endodermal moiety which is also able to change the fate
of heterologous mesodermal cells to form intestinal mesenchyme; and (c) the small
intestinal mesenchyme in turn may deliver instructive information as shown in
association with colonic endoderm; yet this effect is not obvious with
nonintestinal endoderms.
 
PMCID: PMC2120088
PMID: 8027179 [PubMed - indexed for MEDLINE]
 
 
73. Genet Res. 1990 Oct-Dec;56(2-3):209-22.
 
Use of triple tissue blastocyst reconstitution to study the development of
diploid parthenogenetic primitive ectoderm in combination with
fertilization-derived trophectoderm and primitive endoderm.
 
Gardner RL, Barton SC, Surani MA.
 
Imperial Cancer Research Fund, Department of Zoology, Oxford.
 
Diploid mouse conceptuses lacking a paternal genome can form morphologically
normal but small fetuses of up to 25 somites, but they invariably fail to develop
beyond mid-gestation. Such conceptuses differ from normal most notably in the
poor development of extra-embryonic tissues which are largely of trophectodermal
and primitive endodermal origin. However, it is not clear whether the demise of
diploid parthenogenetic (P) or gynogenetic (G) conceptuses is attributable
entirely to the defective development of these two tissues or whether
differentiation of the primitive ectoderm, the precursor of the foetus,
extra-embryonic mesoderm and amnion, is also impaired by the absence of a
paternal genome. Therefore, a new blastocyst reconstitution technique was used
which enabled primitive ectoderm from P blastocysts to be combined with primitive
endoderm and trophectoderm from fertilization-derived (F) blastocysts. One third
of the 'triple tissue' reconstituted blastocysts that implanted yielded foetuses.
However, all foetuses recovered on the 11th or 12th day of gestation were small
and, with one exception, either obviously retarded or arrested in development.
The exception was a living 44 somite specimen which is the most advanced P foetus
yet recorded. Foetuses were invariably degenerating in conceptuses recovered on
the 13th day. In contrast, at least 16% of control reconstituted blastocysts with
primitive ectoderm as well as primitive endoderm and trophectoderm of F origin
developed normally on the 13th day of gestation or to term. Hence, the presence
of a paternal genome seems to be essential for normal differentiation of all 3
primary tissues of the mouse blastocyst. The P foetuses that developed from
reconstituted blastocysts were so closely invested by their membranes that they
often showed abnormal flexure of the posterior region of the body. Several also
showed a deficiency of allantoic tissue. Therefore, the possibility that the
defect in development of P primitive ectoderms resided in their extra-embryonic
tissues was investigated by analysing a series of chimaeras produced by injecting
them into intact F blastocysts. The foregoing anomalies were not discernible even
when P cells made a large contribution to the extra-embryonic mesoderm or amnion
plus umbilical cord. Furthermore, selection against P cells was no greater in
extra-embryonic derivatives of the primitive ectoderm than in the foetus itself.
 
PMID: 2272512 [PubMed - indexed for MEDLINE]
 
 
74. Development. 1989 Jun;106(2):407-19.
 
Differential localization of villin and fimbrin during development of the mouse
visceral endoderm and intestinal epithelium.
 
Ezzell RM, Chafel MM, Matsudaira PT.
 
Whitehead Institute for Biomedical Research, Cambridge, Massachusetts.
 
The apical surface of transporting epithelia is specially modified to absorb
nutrients efficiently by amplifying its surface area as microvilli. Each
microvillus is supported by an underlying core of bundled actin filaments. Villin
and fimbrin are two actin-binding proteins that bundle actin filaments in the
intestine and kidney brush border epithelium. To better understand their function
in the assembly of the cytoskeleton during epithelial differentiation, we
examined the pattern of villin and fimbrin expression in the developing mouse
using immunofluorescence and immunoelectron microscopy. Villin is first detected
at day 5 in the primitive endoderm of the postimplantation embryo and is later
restricted to the visceral endoderm. By day 8.5, villin becomes redistributed to
the apical surface in the visceral endoderm, appearing in the gut at day 10 and
concentrating in the apical cytoplasm of the differentiating intestinal
epithelium 2-3 days later. In contrast, fimbrin is found in the oocyte and in all
tissues of the early embryo. In both the visceral endoderm and gut epithelium,
fimbrin concentrates at the apical surface 2-3 days after villin; this
redistribution occurs when the visceral endoderm microvilli first contain
organized microfilament bundles and when microvilli first begin to appear in the
gut. These results suggest a common mechanism of assembly of the absorptive
surface of two different tissues in the embryo and identify villin as a useful
marker for the visceral endoderm.
 
PMID: 2686960 [PubMed - indexed for MEDLINE]
 
 
75. Shi Yan Sheng Wu Xue Bao. 1989 Mar;22(1):43-55.
 
An extensive increase of junctional communication capacity in endoderm
development of the Xenopus embryo.
 
Chen DL.
 
The present result shows that in blastula and gastrula stages although endoderm
cells of the Xenopus embryo may be electrically coupled with each other, most of
them can not detectably transfer the 376 dalton molecular weight tracer, the
carboxyfluorescein, to their contiguous neighbor cells. They become capable of
such junctional dye transfer at the end of gastrulation. This transition reflects
temporally well ordered development of junctional communication capacity from low
to high level, which may be related to the developmental program of endodermal
cellular differentiation. The time course of this transition provides a measure
for study of the effects of various factors on the development of junctional
communication capacity in this embryo.
 
PMID: 2763765 [PubMed - indexed for MEDLINE]
 
 
76. Dev Biol. 1985 Apr;108(2):513-21.
 
Cell surface glycoproteins mediate compaction, trophoblast attachment, and
endoderm formation during early mouse development.
 
Richa J, Damsky CH, Buck CA, Knowles BB, Solter D.
 
Early mouse embryos undergo several morphogenetic processes, such as compaction,
trophoblast attachment, and endoderm formation that can be studied in vitro.
Several polyspecific and monospecific antisera have been used to perturb these
processes in a nontoxic, reversible fashion. One of the antibody-defined
molecules, cell CAM 120/80, promotes epithelial cell adhesion, embryo compaction,
and endoderm formation. The results suggest the presence of another such
molecule(s) involved in these same processes. Evidence is also presented that
another set of antibody-defined molecules, GP 140, involved in attachment of
somatic cells to the substrate, mediates trophoblast attachment of the mouse
blastocyst. The possible role of these molecules in governing the processes
leading to cell lineages in the mouse embryo is discussed.
 
PMID: 4076542 [PubMed - indexed for MEDLINE]
 
 
77. Dev Biol. 1985 Feb;107(2):432-41.
 
Abnormal embryonic development induced by antibodies to rat visceral yolk-sac
endoderm: isolation of the antigen and localization to microvillar membrane.
 
Leung CC, Lee C, Cheewatrakoolpong B, Hilton D.
 
An antigenic substance was isolated from rat visceral yolk-sac endoderm of the
18th-20th days of gestation by extraction with the nonionic detergent Nonidet
P-40, Sephacryl S-300 gel filtration, and Ricinus communis agglutinin affinity
chromatography. The rabbit antiserum directed against this antigenic substance
when injected into pregnant rats during the period of organogenesis caused
abnormal embryonic development, fetal growth retardation, and embryonic death.
Ouchterlony gel diffusion analysis demonstrated that the antiserum formed one
immunoprecipitin band against the crude detergent extract and a complete identity
between the present visceral yolk-sac antigen and the renal glycoprotein antigen
previously isolated (C. C. K. Leung, (1982) J. Exp. Med. 156, 372-384). The
antigen eluted from the antibody affinity column appeared to consist of two major
peptides of 60 and 30 kDa when analyzed by SDS-polyacrylamide gel
electrophoresis. Indirect immunofluorescent and immunoperoxidase localization
studies at the light microscopic level demonstrated that both rat renal proximal
tubule and embryonic visceral yolk-sac endoderm at various gestational stages
(including the organogenetic period) shared the same antigen. Indirect
immunoperoxidase localization studies at the electron microscopic level
demonstrated that the antigen was a part of (or associated with) the microvillar
membrane and membrane invaginations at the base of the microvilli of the renal
proximal tubule and visceral yolk-sac endoderm. In vivo immunoperoxidase
localization studies demonstrated that the teratogenic antibodies localized
within the large phagolysosomes and the apical vesicles of the visceral yolk-sac
endoderm. It is postulated that visceral yolk-sac pathology was induced by the
antibodies.
 
PMID: 3972164 [PubMed - indexed for MEDLINE]
 
 
78. J Embryol Exp Morphol. 1984 Apr;80:251-88.
 
An in situ cell marker for clonal analysis of development of the extraembryonic
endoderm in the mouse.
 
Gardner RL.
 
Conditions were found for staining whole mid-gestation capsular parietal
endoderms and visceral yolk sacs for malic enzyme activity that gave excellent
discrimination between wild-type (Mod-1+/Mod-1+) cells and mutant (Mod-1n/Mod-1n)
cells that lack the cytoplasmic form of the enzyme. Reciprocal blastocyst
injection experiments were undertaken in which single primitive endoderm cells of
one genotype were transplanted into embryos of the other genotype. In addition,
Mod-1+/Mod-1+ early inner cell mass (ICM) cells were injected into Mod-1n/Mod-1n
blastocysts, either in groups of two or three singletons or as daughter cell
pairs. A substantial proportion of the resulting conceptuses showed mosaic
histochemical staining in the parietal endoderm, visceral yolk sac, or in both
these membranes. Stained cells were invariably intimately intermixed with
unstained cells in the mosaic parietal endoderms. In contrast, one or both of two
distinct patterns of staining could be discerned in mosaic visceral yolk sacs.
The first, a conspicuously 'coherent' pattern, was found to be due to endodermal
chimaerism; the second, a more diffuse pattern, was attributable to chimaerism in
the mesodermal layer of this membrane. The overall distribution of cells with
donor staining characteristics resulting from primitive endoderm versus early ICM
cell injections was consistent with findings in earlier experiments in which
allozymes of glucosephosphate isomerase were used as markers. The conspicuous
lack of phenotypically intermediate cells in predominantly stained areas of
mosaic membranes suggested that the histochemical difference between
Mod-1+/Mod-1+ and Mod-1n/Mod-1n genotypes was cell-autonomous. This conclusion
was strengthened by the results of staining mixed in vitro cultures of parietal
endoderm in which presence or absence of phagocytosed melanin granules was used
as an independent means of distinguishing wild type from null cells. By
substituting tetranitro blue tetrazolium for nitro blue tetrazolium in the
incubation medium, satisfactory differential staining was obtained for both the
extraembryonic endoderm and other tissues of earlier postimplantation wild type
versus null embryos. Finally, absence of cytoplasmic malic enzyme activity does
not appear to have a significant effect on the viability or behaviour of mutant
cells.
 
PMID: 6205114 [PubMed - indexed for MEDLINE]
 
 
79. Pediatr Res. 1983 May;17(5):313-8.
 
Antiserum to rat visceral yolk sac endoderm induced abnormal embryonic
development.


Leung CC.


The induction of abnormal embryonic development by heterologous tissue antisera
59: Casey ES, Tada M, Fairclough L, Wylie CC, Heasman J, Smith JC. Bix4 is
has been well established. The underlying mechanism whereby such teratogenesis
activated directly by VegT and mediates endoderm formation in Xenopus
occurs is not known. There were implications that visceral yolk sac endoderm
development. Development. 1999 Oct;126(19):4193-200. PubMed PMID: 10477288.
might be involved. Endoderm was isolated from rat visceral yolk sac of 14th day
of gestation using a nonenzymic procedure. The purity of the endoderm preparation
was examined by electron microscopy. The preparation contained sheets of single
layer of endodermal cells with no apparent contamination by the underlying
mesenchyme or basal lamina. The specificity of the antiserum was examined by in
vitro immunofluorescent localization studies. The antibodies against the endoderm
localized only in the endodermal cells and some of the renal tubular cells.
Intraperitoneal injection of the endoderm antiserum into 9-day pregnant rats
resulted in congenital malformation, embryonic death, and fetal growth
retardation. The effects of the antiserum were dose-dependent. The most
frequently observed defects were anophthalmia and microphthalmia. Retarding
effect of the antiserum on the growth of the embryo at the egg cylinder stage was
also observed. In vivo immunofluorescent localization studies indicated that the
endoderm antibodies localized only in the endodermal cells of the visceral yolk
sac placenta; no localization was observed in the visceral yolk sac mesenchyme,
basal lamina. Reichert's membrane, maternal kidney tissue or the embryo proper.


PMID: 6343995 [PubMed - indexed for MEDLINE]


60: Weaver M, Yingling JM, Dunn NR, Bellusci S, Hogan BL. Bmp signaling regulates
proximal-distal differentiation of endoderm in mouse lung development.
Development. 1999 Sep;126(18):4005-15. PubMed PMID: 10457010.


80. C R Seances Acad Sci III. 1982 Sep 20;295(2):89-92.


[Development of the adenylate cyclase activity of the embryonic chorda-mesoderm
61: Bielinska M, Narita N, Wilson DB. Distinct roles for visceral endoderm during
and endoderm during the migration of primordial germ cells in Xenopus laevis
embryonic mouse development. Int J Dev Biol. 1999 May;43(3):183-205. Review.
(anuran amphibian)]
PubMed PMID: 10410899.


[Article in French]


Brustis JJ, Galante M, Peyret D.
62: Jung J, Zheng M, Goldfarb M, Zaret KS. Initiation of mammalian liver
development from endoderm by fibroblast growth factors. Science. 1999 Jun
18;284(5422):1998-2003. PubMed PMID: 10373120.


In the embryo of Xenopus laevis, adenylate cyclase activity is higher in the
chorda-mesoderm than in the endoderm. The peak of activity in the chorda-mesoderm
is observed at the beginning of the migration of the primordial germ cells (PGC).
There could be a correlation between the adenylate cyclase activity of the
chorda-mesoderm and the intraendodermic migration of the PGC.


PMID: 6816405 [PubMed - indexed for MEDLINE]
63: Zhu X, Sasse J, Lough J. Evidence that FGF receptor signaling is necessary
for endoderm-regulated development of precardiac mesoderm. Mech Ageing Dev. 1999
Apr 1;108(1):77-85. PubMed PMID: 10366041.




81. J Embryol Exp Morphol. 1979 Aug;52:49-62.
64: Fuss B, Hoch M. Drosophila endoderm development requires a novel homeobox
gene which is a target of Wingless and Dpp signalling. Mech Dev. 1998
Dec;79(1-2):83-97. PubMed PMID: 10349623.


The development of hepatogenic potency in the endoderm of quail embryos.


Fukuda S.
65: Warga RM, Nüsslein-Volhard C. Origin and development of the zebrafish
endoderm. Development. 1999 Feb;126(4):827-38. PubMed PMID: 9895329.


Hepatogenic potency of the endoderm is detectable in the anterior half of the
endoderm of quail embryos older than 2-somite stage when endodermal fragments are
cultured with or without heterologous chick mesenchymes, in the coelomic cavity
of 3-day chick embryos. On the other hand, the posterior half of the endoderm
never has hepatogenic potency. The hepatogenic potency of the endoderm is
gradually stabilised with increasing age. However, expression of hepatogenesis
can be affected when the endoderm is associated with inductively active digestive
tract mesenchymes. Mesenchyme taken from the presumptive cardiac region
('cardiac' mesenchyme) of chick embryos is necessary for the uncommitted anterior
endoderm to acquire hepatogenic potency, and this effect is specific for the
'cardiac' mesenchyme. The 'cardiac' mesenchyme, however, fails to induce hepatic
epithelium in the allantoic endoderm, which can differentiate heterotypically
when cultured in combination with digestive tract mesenchymes. The evidence
presented in this study suggests that the effect of 'cardiac' mesenchyme on the
acquisition of hepatogenic potency in the endoderm is limited.


PMID: 521753 [PubMed - indexed for MEDLINE]
66: Henry GL, Melton DA. Mixer, a homeobox gene required for endoderm
development. Science. 1998 Jul 3;281(5373):91-6. PubMed PMID: 9651252.




82. Anat Embryol (Berl). 1978 Jun 2;153(2):167-78.
67: Kim SK, Hebrok M, Melton DA. Notochord to endoderm signaling is required for
pancreas development. Development. 1997 Nov;124(21):4243-52. PubMed PMID:
9334273.


Development of the chick embryo endoderm studied by S.E.M.


Wakely J, England MA.
68: Hiemisch H, Schütz G, Kaestner KH. Transcriptional regulation in endoderm
development: characterization of an enhancer controlling Hnf3g expression by
transgenesis and targeted mutagenesis. EMBO J. 1997 Jul 1;16(13):3995-4006.
PubMed PMID: 9233809; PubMed Central PMCID: PMC1170023.


PMID: 677469 [PubMed - indexed for MEDLINE]


69: Nishida H, Kumano G. Analysis of the temporal expression of endoderm-specific
alkaline phosphatase during development of the ascidian Halocynthia roretzi. Dev
Growth Differ. 1997 Apr;39(2):199-205. PubMed PMID: 9108333.


83. C R Acad Sci Hebd Seances Acad Sci D. 1977 May 2;284(17):1713-6.


[Induction of the mesoderm and primordial germ cells by the endoderm of
70: Rehorn KP, Thelen H, Michelson AM, Reuter R. A molecular aspect of
Pleurodeles waltlii (Amphibia, Urodele): development during gastrulation]
hematopoiesis and endoderm development common to vertebrates and Drosophila.
Development. 1996 Dec;122(12):4023-31. PubMed PMID: 9012522.


[Article in French]


Maufroid JP, Capuron A.
71: Rasweiler JJ 4th, Badwaik NK. Unusual aspects of inner cell mass formation,
endoderm differentiation, Reichert's membrane development, and amniogenesis in
the lesser bulldog bat, Noctilio albiventris. Anat Rec. 1996 Oct;246(2):293-304.
PubMed PMID: 8888970.


Blastulae ectoderm is combined with dorsal or ventral endoderm from blastulae,
gastrulae and early neurulae. In vitro culture reveals the presence of different
mesodermal structures whose nature is connected with the endoderm origin site.
Primordial germ cells differentiate essentially in the recombinates including
ventral endoderm. The inducing capacity of this latter concerning germ cells is
maximum at the beginning of gastrulation, then decreases during it and finally
disappears at the onset of neurulation.


PMID: 406093 [PubMed - indexed for MEDLINE]
72: Duluc I, Freund JN, Leberquier C, Kedinger M. Fetal endoderm primarily holds
the temporal and positional information required for mammalian intestinal
development. J Cell Biol. 1994 Jul;126(1):211-21. PubMed PMID: 8027179; PubMed
Central PMCID: PMC2120088.




84. Am J Anat. 1976 May;146(1):1-30.
73: Gardner RL, Barton SC, Surani MA. Use of triple tissue blastocyst
reconstitution to study the development of diploid parthenogenetic primitive
ectoderm in combination with fertilization-derived trophectoderm and primitive
endoderm. Genet Res. 1990 Oct-Dec;56(2-3):209-22. PubMed PMID: 2272512.


Cytological development of yolk sac endoderm and protein-absorptive mesothelium
in the little brown bat, Myotis lucifugus.


Enders AC, Wimsatt WA, King BF.
74: Ezzell RM, Chafel MM, Matsudaira PT. Differential localization of villin and
fimbrin during development of the mouse visceral endoderm and intestinal
epithelium. Development. 1989 Jun;106(2):407-19. PubMed PMID: 2686960.


The yolk sac of the little brown bat is unusual in that during the course of
gestation both the inner endodermal cells (bordering the yolk sac cavity) and
outer mesothelium (facing the exocelom) form simple columnar epithelia which
persist throughout gestation. These endodermal cells develop an extensive system
of agranular endoplasmic reticulum, numerous lipid droplets and unusual "giant"
mitochondria. During development the Golgi apparatus changes position from the
apical to the basal side of the nucleus, reversing the polarity of the cells. In
general, the endodermal cells have cytological features suggestive of synthetic
or secretory activity. The mesothelial cells develop an extensive "absorptive
apparatus" in their apices, while large crystalloid-containing granules become
numerous in their basal cytoplasm. The mesothelial cells have large deposits of
glycogen, especially during mid-gestation, but few mitochondria and little
granular endoplasmic reticulum. Endodermal cells do not absorb exogenous protein
(peroxidase) even if it is injected directly into the yolk sac cavity. However,
placement of peroxidase either in the exocelom or in the maternal vascular system
results in the appearance of this protein in the "absorptive apparatus" of
mesothelial cells as well as in macrophages in the stroma of the yolk sac. While
evidence of absorption was clear, no direct evidence of transport of tracer to
fetal blood vascular system was obtained. It is postulated that a major function
of the hypertrophied mesothelial cells during gestation is the absorption of
proteins and possibly other substances from the exocelomic fluid. The major
function of the hypertrophied endodermal cells may be synthesis and secretion of
substances into the fetal circulation.


PMID: 945685 [PubMed - indexed for MEDLINE]
75: Chen DL. An extensive increase of junctional communication capacity in
endoderm development of the Xenopus embryo. Shi Yan Sheng Wu Xue Bao. 1989
Mar;22(1):43-55. PubMed PMID: 2763765.




85. Dev Biol. 1971 Dec;26(4):547-59.
76: Richa J, Damsky CH, Buck CA, Knowles BB, Solter D. Cell surface glycoproteins
mediate compaction, trophoblast attachment, and endoderm formation during early
mouse development. Dev Biol. 1985 Apr;108(2):513-21. PubMed PMID: 4076542.


Differentiation of parietal endoderm cells of the guinea pig yolk sac, with
particular reference to the development of endoplasmic reticulum.


King BF.
77: Leung CC, Lee C, Cheewatrakoolpong B, Hilton D. Abnormal embryonic
development induced by antibodies to rat visceral yolk-sac endoderm: isolation of
the antigen and localization to microvillar membrane. Dev Biol. 1985
Feb;107(2):432-41. PubMed PMID: 3972164.


PMID: 5134612 [PubMed - indexed for MEDLINE]


78: Gardner RL. An in situ cell marker for clonal analysis of development of the
extraembryonic endoderm in the mouse. J Embryol Exp Morphol. 1984 Apr;80:251-88.
PubMed PMID: 6205114.


86. C R Seances Soc Biol Fil. 1971;165(9):1972-5.


[Attempt at in vitro analysis of the inhibitor effect exerted by the somitic
79: Leung CC. Antiserum to rat visceral yolk sac endoderm induced abnormal
mesenchyme on the development of the hepatic endoderm]
embryonic development. Pediatr Res. 1983 May;17(5):313-8. PubMed PMID: 6343995.


[Article in French]


Fontaine J, Le Dougarin N.
80: Brustis JJ, Galante M, Peyret D. [Development of the adenylate cyclase
activity of the embryonic chorda-mesoderm and endoderm during the migration of
primordial germ cells in Xenopus laevis (anuran amphibian)]. C R Seances Acad Sci
III. 1982 Sep 20;295(2):89-92. French. PubMed PMID: 6816405.


PMID: 4263135 [PubMed - indexed for MEDLINE]


81: Fukuda S. The development of hepatogenic potency in the endoderm of quail
embryos. J Embryol Exp Morphol. 1979 Aug;52:49-62. PubMed PMID: 521753.


87. C R Acad Sci Hebd Seances Acad Sci D. 1968 Dec 16;267(25):2174-7.


[Development of differentiation capacities of chick embryo thyroid endoderm after
82: Wakely J, England MA. Development of the chick embryo endoderm studied by
the determination stage]
S.E.M. Anat Embryol (Berl). 1978 Jun 2;153(2):167-78. PubMed PMID: 677469.


[Article in French]


Le Lièvre C, Le Douarin N.
83: Maufroid JP, Capuron A. [Induction of the mesoderm and primordial germ cells
by the endoderm of Pleurodeles waltlii (Amphibia, Urodele): development during
gastrulation]. C R Acad Sci Hebd Seances Acad Sci D. 1977 May 2;284(17):1713-6.
French. PubMed PMID: 406093.


PMID: 4973827 [PubMed - indexed for MEDLINE]


84: Enders AC, Wimsatt WA, King BF. Cytological development of yolk sac endoderm
and protein-absorptive mesothelium in the little brown bat, Myotis lucifugus. Am
J Anat. 1976 May;146(1):1-30. PubMed PMID: 945685.


88. J Embryol Exp Morphol. 1964 Sep;12:551-62.


AN INHERITED ABNORMALITY AFFECTING THE DEVELOPMENT OF THE YOLK PLASMODIUM AND
85: King BF. Differentiation of parietal endoderm cells of the guinea pig yolk
ENDODERM IN DERMESTES MACULATUS (COLEOPTERA).
sac, with particular reference to the development of endoplasmic reticulum. Dev
Biol. 1971 Dec;26(4):547-59. PubMed PMID: 5134612.


EDE DA.


PMID: 14207039 [PubMed - indexed for MEDLINE]
86: Fontaine J, Le Dougarin N. [Attempt at in vitro analysis of the inhibitor
effect exerted by the somitic mesenchyme on the development of the hepatic
endoderm]. C R Seances Soc Biol Fil. 1971;165(9):1972-5. French. PubMed PMID:
4263135.




89. C R Hebd Seances Acad Sci. 1952 Mar 31;234(14):1480-2.
87: Le Lièvre C, Le Douarin N. [Development of differentiation capacities of
chick embryo thyroid endoderm after the determination stage]. C R Acad Sci Hebd
Seances Acad Sci D. 1968 Dec 16;267(25):2174-7. French. PubMed PMID: 4973827.


[Development of the endoderm in bird eggs.]


[Article in Undetermined Language]
88: EDE DA. AN INHERITED ABNORMALITY AFFECTING THE DEVELOPMENT OF THE YOLK
PLASMODIUM AND ENDODERM IN DERMESTES MACULATUS (COLEOPTERA). J Embryol Exp
Morphol. 1964 Sep;12:551-62. PubMed PMID: 14207039.


LUTZ H, REYROLLES J.


PMID: 12979285 [PubMed - indexed for MEDLINE]
89: LUTZ H, REYROLLES J. [Development of the endoderm in bird eggs.]. C R Hebd
Seances Acad Sci. 1952 Mar 31;234(14):1480-2. Undetermined Language. PubMed PMID:
12979285.

Revision as of 09:32, 10 August 2010

Vertebrate Endoderm Development and Organ Formation http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2861293/?tool=pubmed


1: Duboc V, Lapraz F, Saudemont A, Bessodes N, Mekpoh F, Haillot E, Quirin M, Lepage T. Nodal and BMP2/4 pattern the mesoderm and endoderm during development of the sea urchin embryo. Development. 2010 Jan;137(2):223-35. PubMed PMID: 20040489.


2: Holtzinger A, Rosenfeld GE, Evans T. Gata4 directs development of cardiac-inducing endoderm from ES cells. Dev Biol. 2010 Jan 1;337(1):63-73. Epub 2009 Oct 20. PubMed PMID: 19850025; PubMed Central PMCID: PMC2799892.


3: Zorn AM, Wells JM. Vertebrate endoderm development and organ formation. Annu Rev Cell Dev Biol. 2009;25:221-51. Review. PubMed PMID: 19575677; PubMed Central PMCID: PMC2861293.


4: Yang DH, Smith ER, Cai KQ, Xu XX. C-Fos elimination compensates for disabled-2 requirement in mouse extraembryonic endoderm development. Dev Dyn. 2009 Mar;238(3):514-23. PubMed PMID: 19191218; PubMed Central PMCID: PMC2743073.


5: Yagi Y, Ito Y, Kuhara S, Tashiro K. Cephalic hedgehog expression is regulated directly by Sox17 in endoderm development of Xenopus laevis. Cytotechnology. 2008 Jun;57(2):151-9. Epub 2008 Feb 12. PubMed PMID: 19003160; PubMed Central PMCID: PMC2553669.


6: Soares ML, Torres-Padilla ME, Zernicka-Goetz M. Bone morphogenetic protein 4 signaling regulates development of the anterior visceral endoderm in the mouse embryo. Dev Growth Differ. 2008 Sep;50(7):615-21. PubMed PMID: 18657169.


7: Reichenbach B, Delalande JM, Kolmogorova E, Prier A, Nguyen T, Smith CM, Holzschuh J, Shepherd IT. Endoderm-derived Sonic hedgehog and mesoderm Hand2 expression are required for enteric nervous system development in zebrafish. Dev Biol. 2008 Jun 1;318(1):52-64. Epub 2008 Mar 20. PubMed PMID: 18436202; PubMed Central PMCID: PMC2435286.


8: Shin CH, Chung WS, Hong SK, Ober EA, Verkade H, Field HA, Huisken J, Stainier DY. Multiple roles for Med12 in vertebrate endoderm development. Dev Biol. 2008 May 15;317(2):467-79. Epub 2008 Mar 4. PubMed PMID: 18394596; PubMed Central PMCID: PMC2435012.


9: Matsushita S, Urase K, Komatsu A, Scotting PJ, Kuroiwa A, Yasugi S. Foregut endoderm is specified early in avian development through signal(s) emanating from Hensen's node or its derivatives. Mech Dev. 2008 May-Jun;125(5-6):377-95. Epub 2008 Feb 20. PubMed PMID: 18374547.


10: Warkman AS, Yatskievych TA, Hardy KM, Krieg PA, Antin PB. Myocardin expression during avian embryonic heart development requires the endoderm but is independent of BMP signaling. Dev Dyn. 2008 Jan;237(1):216-21. PubMed PMID: 18069699.


11: Manfroid I, Delporte F, Baudhuin A, Motte P, Neumann CJ, Voz ML, Martial JA, Peers B. Reciprocal endoderm-mesoderm interactions mediated by fgf24 and fgf10 govern pancreas development. Development. 2007 Nov;134(22):4011-21. Epub 2007 Oct 17. PubMed PMID: 17942484.


12: McLin VA, Rankin SA, Zorn AM. Repression of Wnt/beta-catenin signaling in the anterior endoderm is essential for liver and pancreas development. Development. 2007 Jun;134(12):2207-17. Epub 2007 May 16. PubMed PMID: 17507400.


13: Zorn AM, Wells JM. Molecular basis of vertebrate endoderm development. Int Rev Cytol. 2007;259:49-111. Review. PubMed PMID: 17425939.


14: Pal R, Khanna A. Heart development: the battle between mesoderm and endoderm. Stem Cells Dev. 2007 Feb;16(1):3-5. PubMed PMID: 17348801.


15: Brito JM, Teillet MA, Le Douarin NM. An early role for sonic hedgehog from foregut endoderm in jaw development: ensuring neural crest cell survival. Proc Natl Acad Sci U S A. 2006 Aug 1;103(31):11607-12. Epub 2006 Jul 25. PubMed PMID: 16868080; PubMed Central PMCID: PMC1544217.


16: Kobayashi D, Jindo T, Naruse K, Takeda H. Development of the endoderm and gut in medaka, Oryzias latipes. Dev Growth Differ. 2006 Jun;48(5):283-95. PubMed PMID: 16759279.


17: Kwon GS, Fraser ST, Eakin GS, Mangano M, Isern J, Sahr KE, Hadjantonakis AK, Baron MH. Tg(Afp-GFP) expression marks primitive and definitive endoderm lineages during mouse development. Dev Dyn. 2006 Sep;235(9):2549-58. PubMed PMID: 16708394; PubMed Central PMCID: PMC1850385.


18: Hiraga Y, Kihara A, Sano T, Igarashi Y. Changes in S1P1 and S1P2 expression during embryonal development and primitive endoderm differentiation of F9 cells. Biochem Biophys Res Commun. 2006 Jun 9;344(3):852-8. Epub 2006 Apr 19. PubMed PMID: 16631609.


19: Bohnsack BL, Lai L, Northrop JL, Justice MJ, Hirschi KK. Visceral endoderm function is regulated by quaking and required for vascular development. Genesis. 2006 Feb;44(2):93-104. PubMed PMID: 16470614.


20: Bort R, Signore M, Tremblay K, Martinez Barbera JP, Zaret KS. Hex homeobox gene controls the transition of the endoderm to a pseudostratified, cell emergent epithelium for liver bud development. Dev Biol. 2006 Feb 1;290(1):44-56. Epub 2005 Dec 20. PubMed PMID: 16364283.


21: Doherty JR, Zhu H, Kuliyev E, Mead PE. Determination of the minimal domains of Mix.3/Mixer required for endoderm development. Mech Dev. 2006 Jan;123(1):56-66. Epub 2005 Dec 5. PubMed PMID: 16330190.


22: Murakami R, Okumura T, Uchiyama H. GATA factors as key regulatory molecules in the development of Drosophila endoderm. Dev Growth Differ. 2005 Dec;47(9):581-9. Review. PubMed PMID: 16316403.


23: Graham A, Okabe M, Quinlan R. The role of the endoderm in the development and evolution of the pharyngeal arches. J Anat. 2005 Nov;207(5):479-87. Review. PubMed PMID: 16313389; PubMed Central PMCID: PMC1571564.


24: Dickinson K, Leonard J, Baker JC. Genomic profiling of mixer and Sox17beta targets during Xenopus endoderm development. Dev Dyn. 2006 Feb;235(2):368-81. PubMed PMID: 16278889.


25: Matsuura R, Kogo H, Ogaeri T, Miwa T, Kuwahara M, Kanai Y, Nakagawa T, Kuroiwa A, Fujimoto T, Torihashi S. Crucial transcription factors in endoderm and embryonic gut development are expressed in gut-like structures from mouse ES cells. Stem Cells. 2006 Mar;24(3):624-30. Epub 2005 Oct 6. PubMed PMID: 16210401.


26: Fukuda K, Kikuchi Y. Endoderm development in vertebrates: fate mapping, induction and regional specification. Dev Growth Differ. 2005 Aug;47(6):343-55. Review. PubMed PMID: 16109032.


27: Maduro MF, Kasmir JJ, Zhu J, Rothman JH. The Wnt effector POP-1 and the PAL-1/Caudal homeoprotein collaborate with SKN-1 to activate C. elegans endoderm development. Dev Biol. 2005 Sep 15;285(2):510-23. PubMed PMID: 16084508.


28: Crump JG, Swartz ME, Kimmel CB. An integrin-dependent role of pouch endoderm in hyoid cartilage development. PLoS Biol. 2004 Sep;2(9):E244. Epub 2004 Jul 20. PubMed PMID: 15269787; PubMed Central PMCID: PMC479042.


29: Kubo A, Shinozaki K, Shannon JM, Kouskoff V, Kennedy M, Woo S, Fehling HJ, Keller G. Development of definitive endoderm from embryonic stem cells in culture. Development. 2004 Apr;131(7):1651-62. Epub 2004 Mar 3. PubMed PMID: 14998924.


30: Ober EA, Olofsson B, Mäkinen T, Jin SW, Shoji W, Koh GY, Alitalo K, Stainier DY. Vegfc is required for vascular development and endoderm morphogenesis in zebrafish. EMBO Rep. 2004 Jan;5(1):78-84. PubMed PMID: 14710191; PubMed Central PMCID: PMC1298958.


31: Berger TM, Hirsch E, Djonov V, Schittny JC. Loss of beta1-integrin-deficient cells during the development of endoderm-derived epithelia. Anat Embryol (Berl). 2003 Dec;207(4-5):283-8. Epub 2003 Nov 25. PubMed PMID: 14648219.


32: Macatee TL, Hammond BP, Arenkiel BR, Francis L, Frank DU, Moon AM. Ablation of specific expression domains reveals discrete functions of ectoderm- and endoderm-derived FGF8 during cardiovascular and pharyngeal development. Development. 2003 Dec;130(25):6361-74. PubMed PMID: 14623825; PubMed Central PMCID: PMC1876660.


33: Hinman VF, Nguyen AT, Davidson EH. Expression and function of a starfish Otx ortholog, AmOtx: a conserved role for Otx proteins in endoderm development that predates divergence of the eleutherozoa. Mech Dev. 2003 Oct;120(10):1165-76. PubMed PMID: 14568105.


34: Finley KR, Tennessen J, Shawlot W. The mouse secreted frizzled-related protein 5 gene is expressed in the anterior visceral endoderm and foregut endoderm during early post-implantation development. Gene Expr Patterns. 2003 Oct;3(5):681-4. PubMed PMID: 12972006.


35: Tam PP, Kanai-Azuma M, Kanai Y. Early endoderm development in vertebrates: lineage differentiation and morphogenetic function. Curr Opin Genet Dev. 2003 Aug;13(4):393-400. Review. PubMed PMID: 12888013.


36: Goldin SN, Papaioannou VE. Paracrine action of FGF4 during periimplantation development maintains trophectoderm and primitive endoderm. Genesis. 2003 May;36(1):40-7. PubMed PMID: 12748966.


37: Pera EM, Martinez SL, Flanagan JJ, Brechner M, Wessely O, De Robertis EM. Darmin is a novel secreted protein expressed during endoderm development in Xenopus. Gene Expr Patterns. 2003 May;3(2):147-52. PubMed PMID: 12711541.


38: Clements D, Cameleyre I, Woodland HR. Redundant early and overlapping larval roles of Xsox17 subgroup genes in Xenopus endoderm development. Mech Dev. 2003 Mar;120(3):337-48. PubMed PMID: 12591603.


39: Ober EA, Field HA, Stainier DY. From endoderm formation to liver and pancreas development in zebrafish. Mech Dev. 2003 Jan;120(1):5-18. Review. PubMed PMID: 12490292.


40: Shivdasani RA. Molecular regulation of vertebrate early endoderm development. Dev Biol. 2002 Sep 15;249(2):191-203. Review. PubMed PMID: 12221001.


41: Dathan N, Parlato R, Rosica A, De Felice M, Di Lauro R. Distribution of the titf2/foxe1 gene product is consistent with an important role in the development of foregut endoderm, palate, and hair. Dev Dyn. 2002 Aug;224(4):450-6. PubMed PMID: 12203737.


42: de Santa Barbara P, Roberts DJ. Tail gut endoderm and gut/genitourinary/tail development: a new tissue-specific role for Hoxa13. Development. 2002 Feb;129(3):551-61. PubMed PMID: 11830557; PubMed Central PMCID: PMC2435615.


43: Matsushita S, Ishii Y, Scotting PJ, Kuroiwa A, Yasugi S. Pre-gut endoderm of chick embryos is regionalized by 1.5 days of development. Dev Dyn. 2002 Jan;223(1):33-47. PubMed PMID: 11803568.


44: Bahary N, Zon LI. Development. Endothelium--chicken soup for the endoderm. Science. 2001 Oct 19;294(5542):530-1. Epub 2001 Sep 27. PubMed PMID: 11577202.


45: Andrews GK, Lee DK, Ravindra R, Lichtlen P, Sirito M, Sawadogo M, Schaffner W. The transcription factors MTF-1 and USF1 cooperate to regulate mouse metallothionein-I expression in response to the essential metal zinc in visceral endoderm cells during early development. EMBO J. 2001 Mar 1;20(5):1114-22. PubMed PMID: 11230134; PubMed Central PMCID: PMC145491.


46: Livingston B, David ES, Thurm C. Gene expression in the endoderm during sea urchin development. Zygote. 2000;8 Suppl 1:S35-6. Review. PubMed PMID: 11191300.


47: Kimura C, Yoshinaga K, Tian E, Suzuki M, Aizawa S, Matsuo I. Visceral endoderm mediates forebrain development by suppressing posteriorizing signals. Dev Biol. 2000 Sep 15;225(2):304-21. PubMed PMID: 10985852.


48: Bogue CW, Ganea GR, Sturm E, Ianucci R, Jacobs HC. Hex expression suggests a role in the development and function of organs derived from foregut endoderm. Dev Dyn. 2000 Sep;219(1):84-9. PubMed PMID: 10974674.


49: Vesque C, Ellis S, Lee A, Szabo M, Thomas P, Beddington R, Placzek M. Development of chick axial mesoderm: specification of prechordal mesoderm by anterior endoderm-derived TGFbeta family signalling. Development. 2000 Jul;127(13):2795-809. PubMed PMID: 10851126.


50: Lough J, Sugi Y. Endoderm and heart development. Dev Dyn. 2000 Apr;217(4):327-42. Review. PubMed PMID: 10767078.


51: Shoichet SA, Malik TH, Rothman JH, Shivdasani RA. Action of the Caenorhabditis elegans GATA factor END-1 in Xenopus suggests that similar mechanisms initiate endoderm development in ecdysozoa and vertebrates. Proc Natl Acad Sci U S A. 2000 Apr 11;97(8):4076-81. PubMed PMID: 10760276; PubMed Central PMCID: PMC18153.


52: Grapin-Botton A, Melton DA. Endoderm development: from patterning to organogenesis. Trends Genet. 2000 Mar;16(3):124-30. Review. PubMed PMID: 10689353.


53: Gerhart J. Pieter Nieuwkoop's contributions to the understanding of meso-endoderm induction and neural induction in chordate development. Int J Dev Biol. 1999;43(7):605-13. PubMed PMID: 10668970.


54: Cleaver O, Seufert DW, Krieg PA. Endoderm patterning by the notochord: development of the hypochord in Xenopus. Development. 2000 Feb;127(4):869-79. PubMed PMID: 10648245.


55: Wells JM, Melton DA. Vertebrate endoderm development. Annu Rev Cell Dev Biol. 1999;15:393-410. Review. PubMed PMID: 10611967.


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57: Dale L. Vertebrate development: Multiple phases to endoderm formation. Curr Biol. 1999 Nov 4;9(21):R812-5. PubMed PMID: 10556077.


58: Ristoratore F, Spagnuolo A, Aniello F, Branno M, Fabbrini F, Di Lauro R. Expression and functional analysis of Cititf1, an ascidian NK-2 class gene, suggest its role in endoderm development. Development. 1999 Nov;126(22):5149-59. PubMed PMID: 10529431.


59: Casey ES, Tada M, Fairclough L, Wylie CC, Heasman J, Smith JC. Bix4 is activated directly by VegT and mediates endoderm formation in Xenopus development. Development. 1999 Oct;126(19):4193-200. PubMed PMID: 10477288.


60: Weaver M, Yingling JM, Dunn NR, Bellusci S, Hogan BL. Bmp signaling regulates proximal-distal differentiation of endoderm in mouse lung development. Development. 1999 Sep;126(18):4005-15. PubMed PMID: 10457010.


61: Bielinska M, Narita N, Wilson DB. Distinct roles for visceral endoderm during embryonic mouse development. Int J Dev Biol. 1999 May;43(3):183-205. Review. PubMed PMID: 10410899.


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63: Zhu X, Sasse J, Lough J. Evidence that FGF receptor signaling is necessary for endoderm-regulated development of precardiac mesoderm. Mech Ageing Dev. 1999 Apr 1;108(1):77-85. PubMed PMID: 10366041.


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66: Henry GL, Melton DA. Mixer, a homeobox gene required for endoderm development. Science. 1998 Jul 3;281(5373):91-6. PubMed PMID: 9651252.


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77: Leung CC, Lee C, Cheewatrakoolpong B, Hilton D. Abnormal embryonic development induced by antibodies to rat visceral yolk-sac endoderm: isolation of the antigen and localization to microvillar membrane. Dev Biol. 1985 Feb;107(2):432-41. PubMed PMID: 3972164.


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81: Fukuda S. The development of hepatogenic potency in the endoderm of quail embryos. J Embryol Exp Morphol. 1979 Aug;52:49-62. PubMed PMID: 521753.


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84: Enders AC, Wimsatt WA, King BF. Cytological development of yolk sac endoderm and protein-absorptive mesothelium in the little brown bat, Myotis lucifugus. Am J Anat. 1976 May;146(1):1-30. PubMed PMID: 945685.


85: King BF. Differentiation of parietal endoderm cells of the guinea pig yolk sac, with particular reference to the development of endoplasmic reticulum. Dev Biol. 1971 Dec;26(4):547-59. PubMed PMID: 5134612.


86: Fontaine J, Le Dougarin N. [Attempt at in vitro analysis of the inhibitor effect exerted by the somitic mesenchyme on the development of the hepatic endoderm]. C R Seances Soc Biol Fil. 1971;165(9):1972-5. French. PubMed PMID: 4263135.


87: Le Lièvre C, Le Douarin N. [Development of differentiation capacities of chick embryo thyroid endoderm after the determination stage]. C R Acad Sci Hebd Seances Acad Sci D. 1968 Dec 16;267(25):2174-7. French. PubMed PMID: 4973827.


88: EDE DA. AN INHERITED ABNORMALITY AFFECTING THE DEVELOPMENT OF THE YOLK PLASMODIUM AND ENDODERM IN DERMESTES MACULATUS (COLEOPTERA). J Embryol Exp Morphol. 1964 Sep;12:551-62. PubMed PMID: 14207039.


89: LUTZ H, REYROLLES J. [Development of the endoderm in bird eggs.]. C R Hebd Seances Acad Sci. 1952 Mar 31;234(14):1480-2. Undetermined Language. PubMed PMID: 12979285.

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