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Cite this page: Hill, M.A. (2021, December 5) Embryology Pig Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Pig_Development
10 Most Recent Papers
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<pubmed limit=5>Pig Development</pubmed>
<pubmed limit=5>Pig Embryology</pubmed>
Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo
PLoS One. 2016 Mar 18;11(3):e0151737. doi: 10.1371/journal.pone.0151737.
Xue B1, Li Y1, He Y1, Wei R1, Sun R2, Yin Z1, Bou G1, Liu Z1.
Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC) line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP) positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs) could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs. PMID 26991423
An In Vivo Three-Dimensional Magnetic Resonance Imaging-Based Averaged Brain Collection of the Neonatal Piglet (Sus scrofa)
PLoS One. 2014 Sep 25;9(9):e107650. doi: 10.1371/journal.pone.0107650. eCollection 2014.
Conrad MS1, Sutton BP2, Dilger RN3, Johnson RW4.
Due to the fact that morphology and perinatal growth of the piglet brain is similar to humans, use of the piglet as a translational animal model for neurodevelopmental studies is increasing. Magnetic resonance imaging (MRI) can be a powerful tool to study neurodevelopment in piglets, but many of the MRI resources have been produced for adult humans. Here, we present an average in vivo MRI-based atlas specific for the 4-week-old piglet. In addition, we have developed probabilistic tissue classification maps. These tools can be used with brain mapping software packages (e.g. SPM and FSL) to aid in voxel-based morphometry and image analysis techniques. The atlas enables efficient study of neurodevelopment in a highly tractable translational animal with brain growth and development similar to humans.
Specific gene-regulation networks during the pre-implantation development of the pig embryo as revealed by deep sequencing
BMC Genomics. 2014 Jan 3;15:4. doi: 10.1186/1471-2164-15-4.
Cao S, Han J1, Wu J, Li Q, Liu S, Zhang W, Pei Y, Ruan X, Liu Z, Wang X, Lim B, Li N.
BACKGROUND: Because few studies exist to describe the unique molecular network regulation behind pig pre-implantation embryonic development (PED), genetic engineering in the pig embryo is limited. Also, this lack of research has hindered derivation and application of porcine embryonic stem cells and porcine induced pluripotent stem cells (iPSCs). RESULTS: We identified and analyzed the genome wide transcriptomes of pig in vivo-derived and somatic cell nuclear transferred (SCNT) as well as mouse in vivo-derived pre-implantation embryos at different stages using mRNA deep sequencing. Comparison of the pig embryonic transcriptomes with those of mouse and human pre-implantation embryos revealed unique gene expression patterns during pig PED. Pig zygotic genome activation was confirmed to occur at the 4-cell stage via genome-wide gene expression analysis. This activation was delayed to the 8-cell stage in SCNT embryos. Specific gene expression analysis of the putative inner cell mass (ICM) and the trophectoderm (TE) revealed that pig and mouse pre-implantation embryos share regulatory networks during the first lineage segregation and primitive endoderm differentiation, but not during ectoderm commitment. Also, fatty acid metabolism appears to be a unique characteristic of pig pre-implantation embryonic development. In addition, the global gene expression patterns in the pig SCNT embryos were different from those in in vivo-derived pig embryos. CONCLUSIONS: Our results provide a resource for pluripotent stem cell engineering and for understanding pig development.
Uterine biology in pigs and sheep
J Anim Sci Biotechnol. 2012 Jul 16;3(1):23. doi: 10.1186/2049-1891-3-23.
Bazer FW, Song G, Kim J, Dunlap KA, Satterfield MC, Johnson GA, Burghardt RC, Wu G. Source Department of Animal Science, 442D Kleberg Center, 2471 TAMU, Texas A&M University, College Station, TX, 77843-2471, USA. email@example.com.
Abstract There is a dialogue between the developing conceptus (embryo-fetus and associated placental membranes) and maternal uterus which must be established during the peri-implantation period for pregnancy recognition signaling, implantation, regulation of gene expression by uterine epithelial and stromal cells, placentation and exchange of nutrients and gases. The uterus provide a microenvironment in which molecules secreted by uterine epithelia or transported into the uterine lumen represent histotroph required for growth and development of the conceptus and receptivity of the uterus to implantation. Pregnancy recognition signaling mechanisms sustain the functional lifespan of the corpora lutea (CL) which produce progesterone, the hormone of pregnancy essential for uterine functions that support implantation and placentation required for a successful outcome of pregnancy. It is within the peri-implantation period that most embryonic deaths occur due to deficiencies attributed to uterine functions or failure of the conceptus to develop appropriately, signal pregnancy recognition and/or undergo implantation and placentation. With proper placentation, the fetal fluids and fetal membranes each have unique functions to ensure hematotrophic and histotrophic nutrition in support of growth and development of the fetus. The endocrine status of the pregnant female and her nutritional status are critical for successful establishment and maintenance of pregnancy. This review addresses the complexity of key mechanisms that are characteristic of successful reproduction in sheep and pigs and gaps in knowledge that must be the subject of research in order to enhance fertility and reproductive health of livestock species.
A gene expression atlas of the domestic pig
BMC Biol. 2012 Nov 15;10:90. doi: 10.1186/1741-7007-10-90.
Freeman TC, Ivens A, Baillie JK, Beraldi D, Barnett MW, Dorward D, Downing A, Fairbairn L, Kapetanovic R, Raza S, Tomoiu A, Alberio R, Wu C, Su AI, Summers KM, Tuggle CK, Archibald AL, Hume DA. Source The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, EH25 9PS, UK. firstname.lastname@example.org.
ABSTRACT: BACKGROUND: This work describes the first genome-wide analysis of the transcriptional landscape of the pig. A new porcine Affymetrix expression array was designed in order to provide comprehensive coverage of the known pig transcriptome. The new array was used to generate a genome-wide expression atlas of pig tissues derived from 62 tissue/cell types. These data were subjected to network correlation analysis and clustering. RESULTS: The analysis presented here provides a detailed functional clustering of the pig transcriptome where transcripts are grouped according to their expression pattern, so one can infer the function of an uncharacterized gene from the company it keeps and the locations in which it is expressed. We describe the overall transcriptional signatures present in the tissue atlas, where possible assigning those signatures to specific cell populations or pathways. In particular, we discuss the expression signatures associated with the gastrointestinal tract, an organ that was sampled at 15 sites along its length and whose biology in the pig is similar to human. We identify sets of genes that define specialized cellular compartments and region-specific digestive functions. Finally, we performed a network analysis of the transcription factors expressed in the gastrointestinal tract and demonstrate how they sub-divide into functional groups that may control cellular gastrointestinal development. CONCLUSIONS: As an important livestock animal with a physiology that is more similar than mouse to man, we provide a major new resource for understanding gene expression with respect to the known physiology of mammalian tissues and cells. The data and analyses are available on the websites http://biogps.org and http://www.macrophages.com/pig-atlas.
Early developing pig embryos mediate their own environment in the maternal tract
PLoS One. 2012;7(3):e33625. Epub 2012 Mar 28.
Almiñana C, Heath PR, Wilkinson S, Sanchez-Osorio J, Cuello C, Parrilla I, Gil MA, Vazquez JL, Vazquez JM, Roca J, Martinez EA, Fazeli A. Source Academic Unit of Reproductive and Developmental Medicine, Department of Human Metabolism, The University of Sheffield, Sheffield, United Kingdom.
The maternal tract plays a critical role in the success of early embryonic development providing an optimal environment for establishment and maintenance of pregnancy. Preparation of this environment requires an intimate dialogue between the embryo and her mother. However, many intriguing aspects remain unknown in this unique communication system. To advance our understanding of the process by which a blastocyst is accepted by the endometrium and better address the clinical challenges of infertility and pregnancy failure, it is imperative to decipher this complex molecular dialogue. The objective of the present work is to define the local response of the maternal tract towards the embryo during the earliest stages of pregnancy. We used a novel in vivo experimental model that eliminated genetic variability and individual differences, followed by Affymetrix microarray to identify the signals involved in this embryo-maternal dialogue. Using laparoscopic insemination one oviduct of a sow was inseminated with spermatozoa and the contralateral oviduct was injected with diluent. This model allowed us to obtain samples from the oviduct and the tip of the uterine horn containing either embryos or oocytes from the same sow. Microarray analysis showed that most of the transcripts differentially expressed were down-regulated in the uterine horn in response to blastocysts when compared to oocytes. Many of the transcripts altered in response to the embryo in the uterine horn were related to the immune system. We used an in silico mathematical model to demonstrate the role of the embryo as a modulator of the immune system. This model revealed that relatively modest changes induced by the presence of the embryo could modulate the maternal immune response. These findings suggested that the presence of the embryo might regulate the immune system in the maternal tract to allow the refractory uterus to tolerate the embryo and support its development.
Germ layer differentiation during early hindgut and cloaca formation in rabbit and pig embryos
J Anat. 2010 Dec;217(6):665-78. doi: 10.1111/j.1469-7580.2010.01303.x. Epub 2010 Sep 28.
Hassoun R, Schwartz P, Rath D, Viebahn C, Männer J. Source Department of Anatomy and Embryology, Göttingen University, Göttingen, Germany.
Relative to recent advances in understanding molecular requirements for endoderm differentiation, the dynamics of germ layer morphology and the topographical distribution of molecular factors involved in endoderm formation at the caudal pole of the embryonic disc are still poorly defined. To discover common principles of mammalian germ layer development, pig and rabbit embryos at late gastrulation and early neurulation stages were analysed as species with a human-like embryonic disc morphology, using correlative light and electron microscopy. Close intercellular contact but no direct structural evidence of endoderm formation such as mesenchymal-epithelial transition between posterior primitive streak mesoderm and the emerging posterior endoderm were found. However, a two-step process closely related to posterior germ layer differentiation emerged for the formation of the cloacal membrane: (i) a continuous mesoderm layer and numerous patches of electron-dense flocculent extracellular matrix mark the prospective region of cloacal membrane formation; and (ii) mesoderm cells and all extracellular matrix including the basement membrane are lost locally and close intercellular contact between the endoderm and ectoderm is established. The latter process involves single cells at first and then gradually spreads to form a longitudinally oriented seam-like cloacal membrane. These gradual changes were found from gastrulation to early somite stages in the pig, whereas they were found from early somite to mid-somite stages in the rabbit; in both species cloacal membrane formation is complete prior to secondary neurulation. The results highlight the structural requirements for endoderm formation during development of the hindgut and suggest new mechanisms for the pathogenesis of common urogenital and anorectal malformations. © 2010 The Authors. Journal of Anatomy © 2010 Anatomical Society of Great Britain and Ireland.
Temporal and spatial expression of muc1 during implantation in sows
Int J Mol Sci. 2010 May 27;11(6):2322-35.
Ren Q, Guan S, Fu J, Wang A.
College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; E-Mails: email@example.com (Q.R.); firstname.lastname@example.org (S.G.). Abstract Recent evidence points to an important role for Muc1 in embryo implantation. In this study, Real-time PCR and immunohistochemistry were used to study mRNA and protein levels at, and between, the attachment sites of the endometrium of Day 13, 18 and 24 pregnant sows. The results indicate that Muc1 mRNA expression was higher between attachment sites than at attachment sites during implantation and this effect was significant on Day 13 (P < 0.01) and 24 (P < 0.01). Intense Muc1 immunostaining was observed in luminal epithelium and stroma and the staining between attachment sites was stronger than at attachment sites on Days 13 and 18. Collectively, these results suggest the crucial role of Muc1 in successful implantation and embryo survival.
- Porcine embryos begin to attach to the uterus on Days 13–14 of pregnancy
Neurulation in the pig embryo
- Neurulation in the pig embryo. van Straaten HW, Peeters MC, Hekking JW, van der Lende T. Anat Embryol (Berl). 2000 Aug;202(2):75-84. PMID: 10985427
- "Neurulation is based on a multitude of factors and processes generated both inside and outside the neural plate. Although there are models for a general neurulation mechanism, specific sets of factors and processes have been shown to be involved in neurulation depending on developmental time and rostro-caudal location at which neurulation occurred in the species under investigation. To find a common thread amongst these apparently divergent modes of neurulation another representative mammalian species, the pig, was studied here by scanning electron microscopy. The data are compared to a series of descriptions in other species. Furthermore, the relation of axial curvature and neural tube closure rate is investigated. In the pig embryo of 7 somites, the first apposition of the neural folds occurs at somite levels 5-7. This corresponds to closure site I in the mouse embryo. At the next stage the rostral and caudal parts of the rhombencephalic folds appose, leaving an opening in between. Therefore, at this stage four neuropores can be distinguished, of which the anterior and posterior ones will remain open longest. The two rhombencephalic closure sites have no counterpart in the mouse, but do have some resemblance to those of the rabbit. The anterior neuropore closes in three phases: (1) the dorsal folds slowly align and then close instantaneously, the slow progression being likely due to a counteracting effect of the mesencephalic flexure; (2) the dorso-lateral folds close in a zipper-like fashion in caudo-rostral direction; (3) the final round aperture is likely to close by circumferential growth. At the stage of 22 somites the anterior neuropore is completely closed. In contrast to the two de novo closure sites for the anterior neuropore in the mouse embryo, none of these were detected in the pig embryo. The posterior neuropore closes initially very fast in the somitic region, but this process almost stops thereafter. We suggest that the somites force the neural folds to elevate precociously. Between the stages of 8-20 somites the width of the posterior neuropore does not change, while the rate of closure gradually increases; this increase may be due to a catch-up of intrinsic neurulation processes and to the reduction of axial curvature. At the stage of 20-22 somites the posterior neuropore suddenly reduces in size but thereafter a small neuropore remains for 5 somite stages. The closure of the posterior neuropore is completed at the stage of 28 somites."
- 7 somite embryo - first apposition of the neural folds occurs at somite levels 5-7. (corresponds to closure site I in mouse).
- next stage - rostral and caudal parts of the rhombencephalic folds appose, leaving an opening in between. T
- at this stage four neuropores can be distinguished, of which the anterior and posterior ones will remain open longest. (two rhombencephalic closure sites have no counterpart in the mouse, but do have some resemblance to those of the rabbit)
- anterior neuropore closes in three phases
- dorsal folds slowly align and then close instantaneously, the slow progression being likely due to a counteracting effect of the mesencephalic flexure
- dorso-lateral folds close in a zipper-like fashion in caudo-rostral direction
- final round aperture is likely to close by circumferential growth.
22 somite embryo - anterior neuropore is completely closed. (closure sites for the anterior neuropore in mouse embryo, none of these were detected in the pig embryo)
- posterior neuropore
- closes initially very fast in the somitic region, but this process almost stops thereafter. (suggest that the somites force the neural folds to elevate precociously)
- stage 20-22 somites the posterior neuropore suddenly reduces in size but thereafter a small neuropore remains for 5 somite stages.
- closure of the posterior neuropore is completed at the stage of 28 somites.
8-20 somite embryos - the width of the posterior neuropore does not change, while the rate of closure gradually increases; this increase may be due to a catch-up of intrinsic neurulation processes and to the reduction of axial curvature. At the
EST analysis on pig mitochondria reveal novel expression differences between developmental and adult tissues
BMC Genomics. 2007 Oct 11;8:367.
Scheibye-Alsing K, Cirera S, Gilchrist MJ, Fredholm M, Gorodkin J.
Division of Genetics and Bioinformatics, IBHV, University of Copenhagen, Grønnegårdsvej 3, DK-1870 Frederiksberg, Denmark. email@example.com Abstract BACKGROUND: The mitochondria are involved in many basic functions in cells of vertebrates, and can be considered the power generator of the cell. Though the mitochondria have been extensively studied there appear to be only few expression studies of mitochondrial genes involving a large number of tissues and developmental stages. Here, we conduct an analysis using the PigEST resource 1 which contains expression information from 35 tissues distributed on one normalized and 97 non-normalized cDNA libraries of which 24 are from developmental stages. The mitochondrial PigEST resource contains 41,499 mitochondrial sequences.
RESULTS: The mitochondrial EST (Expressed Sequence Tag) sequences were assembled into contigs which covers more than 94 percent of the porcine mitochondrial genome, with an average of 976 EST sequences per nucleotide. This data was converted into expression values for the individual genes in each cDNA library revealing differential expression between genes expressed in cDNA libraries from developmental and adult stages. For the 13 protein coding genes (and several RNA genes), we find one set of six genes, containing all cytochrome oxidases, that are upregulated in developmental tissues, whereas the remaining set of seven genes, containing all ATPases, that are upregulated in adult muscle and brain tissues. Further, the COX I (Cytochrome oxidase subunit one) expression profile differs from that of the remaining genes, which could be explained by a tissue specific cleavage event or degradation pattern, and is especially pronounced in developmental tissues. Finally, as expected cDNA libraries from muscle tissues contain by far the largest amount (up to 20%) of expressed mitochondrial genes.
CONCLUSION: Our results present novel insight into differences in mitochondrial gene expression, emphasizing differences between adult and developmental tissues. Our work indicates that there are presently unknown mechanisms which work to customize mitochondrial processes to the specific needs of the cell, illustrated by the different patterns between adult and developmental tissues. Furthermore, our results also provide novel insight into how in-depth sequencing can provide significant information about expression patterns.