|About Discussion Pages|
Cite this page: Hill, M.A. (2021, April 13) Embryology Splanchnic Mesoderm. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Splanchnic_Mesoderm
Li D, Angermeier A & Wang J. (2019). Planar cell polarity signaling regulates polarized second heart field morphogenesis to promote both arterial and venous pole septation. Development , 146, . PMID: 31488563 DOI. Planar cell polarity signaling regulates polarized second heart field morphogenesis to promote both arterial and venous pole septation
The second heart field (SHF) harbors progenitors that are important for heart formation, but little is known about its morphogenesis. We show that SHF population in the mouse splanchnic mesoderm (SpM-SHF) undergoes polarized morphogenesis to preferentially elongate anteroposteriorly. Loss of Wnt5, a putative ligand of the planar cell polarity (PCP) pathway, causes the SpM-SHF to expand isotropically. Temporal tracking reveals that the Wnt5a lineage is a unique subpopulation specified as early as E7.5, and undergoes bi-directional deployment to form specifically the pulmonary trunk and the dorsal mesenchymal protrusion (DMP). In Wnt5a-/- mutants, Wnt5a lineage fails to extend into the arterial and venous poles, leading to both outflow tract and atrial septation defects that can be rescued by an activated form of PCP effector Daam1. We identify oriented actomyosin cables in the medial SpM-SHF as a potential Wnt5a-mediated mechanism that promotes SpM-SHF lengthening and restricts its widening. Finally, the Wnt5a lineage also contributes to the pulmonary mesenchyme, suggesting that Wnt5a/PCP is a molecular circuit recruited by the recently identified cardiopulmonary progenitors to coordinate morphogenesis of the pulmonary airways and the cardiac septations necessary for pulmonary circulation.This article has an associated 'The people behind the papers' interview. © 2019. Published by The Company of Biologists Ltd. KEYWORDS: Morphogenesis; Planar cell polarity; Second heart field PMID: 31488563 PMCID: PMC6826042 [Available on 2020-10-15] DOI: 10.1242/dev.181719
A Renewable Source of Human Beige Adipocytes for Development of Therapies to Treat Metabolic Syndrome
Cell Rep. 2018 Dec 11;25(11):3215-3228.e9. doi: 10.1016/j.celrep.2018.11.037.
Su S1, Guntur AR1, Nguyen DC1, Fakory SS1, Doucette CC1, Leech C1, Lotana H1, Kelley M1, Kohli J1, Martino J2, Sims-Lucas S3, Liaw L4, Vary C4, Rosen CJ4, Brown AC5. Author information Abstract Molecular- and cellular-based therapies have the potential to reduce obesity-associated disease. In response to cold, beige adipocytes form in subcutaneous white adipose tissue and convert energy stored in metabolic substrates to heat, making them an attractive therapeutic target. We developed a robust method to generate a renewable source of human beige adipocytes from induced pluripotent stem cells (iPSCs). Developmentally, these cells are derived from FOXF1+ mesoderm and progress through an expandable mural-like mesenchymal stem cell (MSC) to form mature beige adipocytes that display a thermogenically active profile. This includes expression of uncoupling protein 1 (UCP1) concomitant with increased uncoupled respiration. With this method, dysfunctional adipogenic precursors can be reprogrammed and differentiated into beige adipocytes with increased thermogenic function and anti-diabetic secretion potential. This resource can be used to (1) elucidate mechanisms that underlie the control of beige adipogenesis and (2) generate material for cellular-based therapies that target metabolic syndrome in humans. Published by Elsevier Inc. KEYWORDS: UCP1; adipogenesis; beige adipocytes; diabetes; mesoderm; metabolic syndrome PMID: 30540952 PMCID: PMC6375695 DOI: 10.1016/j.celrep.2018.11.037
Developmental Mechanism of Limb Field Specification along the Anterior-Posterior Axis during Vertebrate Evolution
J Dev Biol. 2016 May 19;4(2). pii: E18. doi: 10.3390/jdb4020018.
Tanaka M1. Author information Abstract In gnathostomes, limb buds arise from the lateral plate mesoderm at discrete positions along the body axis. Specification of these limb-forming fields can be subdivided into several steps. The lateral plate mesoderm is regionalized into the anterior lateral plate mesoderm (ALPM; cardiac mesoderm) and the posterior lateral plate mesoderm (PLPM). Subsequently, Hox genes appear in a nested fashion in the PLPM and provide positional information along the body axis. The lateral plate mesoderm then splits into the somatic and splanchnic layers. In the somatic layer of the PLPM, the expression of limb initiation genes appears in the limb-forming region, leading to limb bud initiation. Furthermore, past and current work in limbless amphioxus and lampreys suggests that evolutionary changes in developmental programs occurred during the acquisition of paired fins during vertebrate evolution. This review presents these recent advances and discusses the mechanisms of limb field specification during development and evolution, with a focus on the role of Hox genes in this process. KEYWORDS: Hox; Tbx4; Tbx5; evolution; limb field specification; retinoic acid PMID: 29615584 PMCID: PMC5831784 DOI: 10.3390/jdb4020018
The contribution of Islet1-expressing splanchnic mesoderm cells to distinct branchiomeric muscles reveals significant heterogeneity in head muscle development
Development. 2008 Feb;135(4):647-57. doi: 10.1242/dev.007989. Epub 2008 Jan 9.
Nathan E1, Monovich A, Tirosh-Finkel L, Harrelson Z, Rousso T, Rinon A, Harel I, Evans SM, Tzahor E. Author information Abstract During embryogenesis, paraxial mesoderm cells contribute skeletal muscle progenitors, whereas cardiac progenitors originate in the lateral splanchnic mesoderm (SpM). Here we focus on a subset of the SpM that contributes to the anterior or secondary heart field (AHF/SHF), and lies adjacent to the cranial paraxial mesoderm (CPM), the precursors for the head musculature. Molecular analyses in chick embryos delineated the boundaries between the CPM, undifferentiated SpM progenitors of the AHF/SHF, and differentiating cardiac cells. We then revealed the regionalization of branchial arch mesoderm: CPM cells contribute to the proximal region of the myogenic core, which gives rise to the mandibular adductor muscle. SpM cells contribute to the myogenic cells in the distal region of the branchial arch that later form the intermandibular muscle. Gene expression analyses of these branchiomeric muscles in chick uncovered a distinct molecular signature for both CPM- and SpM-derived muscles. Islet1 (Isl1) is expressed in the SpM/AHF and branchial arch in both chick and mouse embryos. Lineage studies using Isl1-Cre mice revealed the significant contribution of Isl1(+) cells to ventral/distal branchiomeric (stylohyoid, mylohyoid and digastric) and laryngeal muscles. By contrast, the Isl1 lineage contributes to mastication muscles (masseter, pterygoid and temporalis) to a lesser extent, with virtually no contribution to intrinsic and extrinsic tongue muscles or extraocular muscles. In addition, in vivo activation of the Wnt/beta-catenin pathway in chick embryos resulted in marked inhibition of Isl1, whereas inhibition of this pathway increased Isl1 expression. Our findings demonstrate, for the first time, the contribution of Isl1(+) SpM cells to a subset of branchiomeric skeletal muscles. PMID: 18184728 PMCID: PMC5851587 DOI: 10.1242/dev.007989
Pitx2 promotes development of splanchnic mesoderm-derived branchiomeric muscle
Development. 2006 Dec;133(24):4891-9. Epub 2006 Nov 15.
Dong F1, Sun X, Liu W, Ai D, Klysik E, Lu MF, Hadley J, Antoni L, Chen L, Baldini A, Francis-West P, Martin JF.
Abstract Recent experiments, showing that both cranial paraxial and splanchnic mesoderm contribute to branchiomeric muscle and cardiac outflow tract (OFT) myocardium, revealed unexpected complexity in development of these muscle groups. The Pitx2 homeobox gene functions in both cranial paraxial mesoderm, to regulate eye muscle, and in splanchnic mesoderm to regulate OFT development. Here, we investigated Pitx2 in branchiomeric muscle. Pitx2 was expressed in branchial arch core mesoderm and both Pitx2 null and Pitx2 hypomorphic embryos had defective branchiomeric muscle. Lineage tracing with a Pitx2cre allele indicated that Pitx2 mutant descendents moved into the first branchial arch. However, markers of both undifferentiated core mesoderm and specified branchiomeric muscle were absent. Moreover, lineage tracing with a Myf5cre allele indicated that branchiomeric muscle specification and differentiation were defective in Pitx2 mutants. Conditional inactivation in mice and manipulation of Pitx2 expression in chick mandible cultures revealed an autonomous function in expansion and survival of branchial arch mesoderm. PMID: 17107996 DOI: 10.1242/dev.02693
Splanchnic (visceral) mesoderm has limb-forming ability according to the position along the rostrocaudal axis in chick embryos
Dev Dyn. 2005 Jun;233(2):256-65.
Yonei-Tamura S1, Ide H, Tamura K. Author information Abstract Positioning of the limb is one of the important events for limb development. In the early stage of embryogenesis, the lateral plate mesoderm splits into two layers and the dorsal layer (the somatic mesoderm) gives rise to a series of distinct structures along the rostrocaudal axis, including the forelimb bud, flank body wall, and hindlimb bud. To determine whether positional information in the somatic mesoderm for regionalization along the rostrocaudal axis is also inherited by the ventral layer of the lateral plate mesoderm (the splanchnic mesoderm), experiments in which the splanchnic mesoderm was transplanted under the ectoderm in an in ovo chick system were carried out. Transplantation of the wing-, flank-, and leg-level splanchnic mesoderm resulted in the formation of wings, nothing, and legs, respectively. These results suggest that the splanchnic mesoderm possesses the ability to form limbs and that the ability differs according to the position along the rostrocaudal axis. The position-specific ability to form limbs suggests that there are some domains involved in the formation of position-specific structures in the digestive tract derived from the splanchnic mesoderm, and results of cell fate tracing supported this possibility. In contrast, analysis of shh expression suggested that the anteroposterior polarity in the limb region seems not to be inherited by the splanchnic mesoderm. We propose that the positioning of limb buds is specified and determined in the very early stage of development of the lateral plate mesoderm before splitting and that the polarity in a limb bud is established after the splitting of the mesoderm. Copyright 2005 Wiley-Liss, Inc PMID: 15844095 DOI: 10.1002/dvdy.20391