Visualization of endogenous BMP signaling during Xenopus development.
The TGF-beta superfamily of growth factors is known to transmit signals to the nucleus mainly through the Smads, intracellular signaling components that are highly conserved from nematodes to humans. The signaling activity of the Smads is regulated by their ligand-stimulated phosphorylation through Ser/Thr kinase receptors. Here, to examine the in vivo role of BMP, we investigated the spatio-temporal activation of BMP-regulated signals during Xenopus development, using a polyclonal antibody that specifically recognizes the phosphorylated form of BMP-regulated Smads. BMP signaling was observed uniformly in embryos as early as stage 7, but was restricted to the ventral side of the embryo at the late blastula stage, supporting the proposed role of BMP4 as a ventralizing factor in Xenopus embryos. In addition, localized staining was detected in several developing organs, consistent with the predicted function of BMP family members in organogenesis.
Division of Morphogenesis, Department of Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka Myodaijicho, Okazaki 444-8585, Japan.
T
T
Kurata
J
J
Nakabayashi
T S
TS
Yamamoto
M
M
Mochii
N
N
Ueno
D000818:Animals; D000918:Antibody Specificity; D015153:Blotting, Western / Q000379:methods; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000276:immunology* / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism; D005260:Female; D018878:Limb Buds / Q000378:metabolism; D010766:Phosphorylation; D015398:Signal Transduction; D051785:Smad Proteins; D013623:Tail / Q000196:embryology; D015534:Trans-Activators / Q000276:immunology* / Q000378:metabolism; D014981:Xenopus / Q000196:embryology*; D029867:Xenopus Proteins
C525809:BMP4 protein, human; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D004268:DNA-Binding Proteins; D051785:Smad Proteins; D015534:Trans-Activators; D029867:Xenopus Proteins; C525812:bmp4 protein, Xenopus