Combinatorial Fgf and Bmp signalling patterns the gastrula ectoderm into prospective neural and epidermal domains.
Studies in fish and amphibia have shown that graded Bmp signalling activity regulates dorsal-to-ventral (DV) patterning of the gastrula embryo. In the ectoderm, it is thought that high levels of Bmp activity promote epidermal development ventrally, whereas secreted Bmp antagonists emanating from the organiser induce neural tissue dorsally. However, in zebrafish embryos, the domain of cells destined to contribute to the spinal cord extends all the way to the ventral side of the gastrula, a long way from the organiser. We show that in vegetal (trunk and tail) regions of the zebrafish gastrula, neural specification is initiated at all DV positions of the ectoderm in a manner that is unaffected by levels of Bmp activity and independent of organiser-derived signals. Instead, we find that Fgf activity is required to induce vegetal prospective neural markers and can do so without suppressing Bmp activity. We further show that Bmp signalling does occur within the vegetal prospective neural domain and that Bmp activity promotes the adoption of caudal fate by this tissue.
Kudoh
Tetsuhiro
T
Department of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK. t.kudoh@ucl.ac.uk
Concha
Miguel L
ML
Houart
Corinne
C
Dawid
Igor B
IB
Wilson
Stephen W
SW
D000818:Animals; D015415:Biomarkers; D019521:Body Patterning; D019485:Bone Morphogenetic Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019070:Cell Lineage; D002465:Cell Movement; D002490:Central Nervous System / Q000196:embryology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004475:Ectoderm / Q000166:cytology / Q000502:physiology*; D005346:Fibroblast Growth Factors / Q000378:metabolism*; D005775:Gastrula / Q000166:cytology / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D006609:High Mobility Group Proteins / Q000235:genetics / Q000378:metabolism; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D020897:Organizers, Embryonic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D055748:SOXB1 Transcription Factors; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors; D015027:Zebrafish / Q000196:embryology; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
D015415:Biomarkers; D019485:Bone Morphogenetic Proteins; D004268:DNA-Binding Proteins; D006023:Glycoproteins; D006609:High Mobility Group Proteins; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D055748:SOXB1 Transcription Factors; D014157:Transcription Factors; D029961:Zebrafish Proteins; D005346:Fibroblast Growth Factors; C054234:chordin