Bone morphogenetic protein antagonism of Spemann's organizer is independent of Wnt signaling.
The Xenopus homeobox gene twin is involved in the Wnt-mediated induction of Spemann's organizer. Additionally, several lines of evidence indicate that bone morphogenetic proteins (BMPs) play a role in repressing the formation of the organizer by antagonizing the expression of genes involved in organizer establishment. In order to determine at what level BMPs exert their effect, we measured the activity of different genes expressed within the organizer region. We report that BMP signaling can antagonize the induction of the dorsal-specific gene goosecoid but is unable to affect Wnt signaling at the level of twin. These results suggest that the antagonistic activities of BMPs in organizer formation occur postzygotically, independent of twin regulation, and that Wnt-like dorsal determinant signaling pathways do not crosstalk with BMPs.
Laurent
M N
MN
Department of Developmental and Cell Biology and the Developmental Biology Center, University of California at Irvine, Irvine, California, 92697-2300, USA.
Cho
K W
KW
D000818:Animals; D001483:Base Sequence; D019521:Body Patterning / Q000235:genetics* / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D017930:Genes, Reporter; D051956:Goosecoid Protein; D018398:Homeodomain Proteins / Q000235:genetics; D008957:Models, Genetic; D012097:Repressor Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014157:Transcription Factors; D014981:Xenopus / Q000196:embryology* / Q000235:genetics* / Q000502:physiology; D029867:Xenopus Proteins