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.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/s1567-133x(03)00091-7 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Primitive to visceral endoderm maturation is essential for mouse epiblast survival beyond implantation.
iScience
January 2025
Mammalian Embryo and Stem Cell Group, University of Cambridge, Department of Physiology, Development and Neuroscience, Downing Street, Cambridge CB2 3DY, UK.
The implantation of the mouse blastocyst initiates a complex sequence of tissue remodeling and cell differentiation events required for morphogenesis, during which the extraembryonic primitive endoderm transitions into the visceral endoderm. Through single-cell RNA sequencing of embryos at embryonic day 5.0, shortly after implantation, we reveal that this transition is driven by dynamic signaling activities, notably the upregulation of BMP signaling and a transient increase in Sox7 expression.
View Article and Find Full Text PDFReichert's membrane - A continuing enigma for developmental biologists.
Dev Biol
January 2025
Developmental Biology & Cancer Department, UCL Great Ormond Street Institute of Child Health, London, UK. Electronic address:
Reichert's membrane (RM) is a basement membrane of gigantic proportions that surrounds the mammalian embryo following implantation. It is part of the parietal yolk sac, which originates from the wall of the preimplantation blastocyst. RM persists from implantation to birth in rodents and analogous structures occur in other mammals, including primates.
View Article and Find Full Text PDFSpatial transcriptomic characterization of a Carnegie stage 7 human embryo.
Nat Cell Biol
January 2025
Key Laboratory of Organ Regeneration and Reconstruction, State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China.
Gastrulation marks a pivotal stage in mammalian embryonic development, establishing the three germ layers and body axis through lineage diversification and morphogenetic movements. However, studying human gastrulating embryos is challenging due to limited access to early tissues. Here we show the use of spatial transcriptomics to analyse a fully intact Carnegie stage 7 human embryo at single-cell resolution, along with immunofluorescence validations in a second embryo.
View Article and Find Full Text PDFTargeted Deletion in the Basal Body Protein Talpid3 Leads to Loss of Primary Cilia in Embryonic Stem Cells and Defective Lineage-Specific Differentiation.
Cells
November 2024
Department of Life Sciences, University of Bath, Building 4 South, Bath BA2 7AY, UK.
Talpid3 is a basal body protein required for the formation of primary cilia, an organelle involved in signal transduction. Here, we asked if Talpid3 has a role in the regulation of differentiation and/or self-renewal of ES cells and whether cells lacking cilia due to a deletion in Talpid3 can be reprogrammed to induced pluripotent stem (iPS) cells. We show that mouse embryonic limb fibroblasts which lack primary cilia with a targeted deletion in the () gene can be efficiently reprogrammed to iPS cells.
View Article and Find Full Text PDFDisease susceptibility implications of preferential inactivation of the paternal X chromosome in extraembryonic endoderm of the mouse.
Dev Biol
March 2025
Department of Genetics and Development Columbia University, New York, NY, USA. Electronic address:
In the mouse, there is preferential inactivation of the paternally-derived X chromosome in extraembryonic tissues of early embryos, including trophectoderm and primitive endoderm or hypoblast. Although derivatives of these tissue have long been considered to be purely extraembryonic in nature, recent studies have shown that hypoblast-derived cells of the 'extraembryonic' visceral endoderm make a substantial cellular contribution to the definitive gut of the fetus. This raises questions about the eventual fate of these cells in the adult and potential disease implications due to the skewed inactivation of the paternally derived X in females heterozygous for X-linked mutations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!