The egg of the direct-developing frog, Eleutherodactylus coqui, has 20 x the volume as that of the model amphibian, Xenopus laevis. Increased egg size led to the origin of nutritional endoderm, a novel cell type that provides nutrition but does not differentiate into digestive tract tissues. As the E. coqui endoderm develops, a distinct boundary exists between differentiating intestinal cells and large yolky cells, which persists even when yolk platelets are depleted. The yolky cells do not become tissues of the digestive tract and are lost, as shown by histology and lineage tracing. EcSox17, an endodermal transcriptional factor, did not distinguish these two cell types, however. When cleavage of the yolky cells was inhibited, embryogenesis continued, indicating that some degree of incomplete cleavage can be tolerated. The presence of cellularized nutritional endoderm in E. coqui may parallel changes that occurred in the evolution of the amniote egg 360 million years ago.
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http://dx.doi.org/10.1002/dvdy.21153 | DOI Listing |
Commun Biol
August 2024
Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, USA.
Intense environmental pressures can yield both regressive and constructive traits through complex evolutionary mechanisms. Although regression is well-studied, the biological bases of constructive features are less well understood. Cave-dwelling Astyanax fish harbor prolific extraoral taste buds on their heads, which are absent in conspecific surface-dwellers.
View Article and Find Full Text PDFbioRxiv
July 2024
Institute of Research, Tokyo Medical and Dental University (TMDU), Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
The induction of tissue-specific vessels in living tissue systems remains challenging. Here, we directly differentiated human pluripotent stem cells into CD32b putative liver sinusoidal progenitors (iLSEP) by dictating developmental pathways. By devising an inverted multilayered air-liquid interface (IMALI) culture, hepatic endoderm, septum mesenchyme, arterial and sinusoidal quadruple progenitors self-organized to generate and sustain hepatocyte-like cells neighbored by divergent endothelial subsets composed of CD32bCD31, LYVE1STAB1CD32bCD31THBDvWF, and LYVE1THBDvWF cells.
View Article and Find Full Text PDFFront Cell Dev Biol
May 2024
Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in Ceske Budejovice, Vodnany, Czechia.
In vertebrates, maternally supplied yolk is typically used in one of two ways: either intracellularly by endodermal cells or extracellularly via the yolk sac. This study delves into the distinctive gut development in sturgeons, which are among the most ancient extant fish groups, contrasting it with that of other vertebrates. Our observations indicate that while sturgeon endodermal cells form the archenteron (i.
View Article and Find Full Text PDFToxicol In Vitro
June 2024
University of Artois, UR 2465, Laboratoire de la Barrière Hémato-Encéphalique (LBHE), Faculté des sciences Jean Perrin, Rue Jean Souvraz SP18, F-62300 Lens, France. Electronic address:
Human induced pluripotent stem cells (iPSC) have the potential to produce desired target cell types in vitro and allow for the high-throughput screening of drugs/chemicals at population level thereby minimising the cost of drug discovery and drug withdrawals after clinical trials. There is a substantial need for the characterisation of the iPSC derived models to better understand and utilise them for toxicological relevant applications. In our study, iPSC (SBAD2 or SBAD3 lines obtained from StemBANCC project) were differentiated towards toxicologically relevant cell types: alveolar macrophages, brain capillary endothelial cells, brain cells, endothelial cells, hepatocytes, lung airway epithelium, monocytes, podocytes and renal proximal tubular cells.
View Article and Find Full Text PDFCell Rep
April 2024
Key Lab of Organic-Based Fertilizers of China and Jiangsu Provincial Key Lab for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing 210095, China. Electronic address:
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