Activation of Stat3 by cytokine receptor gp130 ventralizes Xenopus embryos independent of BMP-4.
Stat3 is one of the main signaling components of cytokine receptors, including gp130. Here we show that activation of cytokine receptor gp130 resulted in a dramatic ventralization of Xenopus embryos and that the ventralization correlated well with Stat3 activation potential of the receptor. This finding led to identification of Xenopus Stat3 (Xstat3), which showed a 95% homology to its murine and human counterparts, at the amino acid level, and was expressed from the one-cell stage throughout development. The mechanism of gp130/XStat3-mediated ventralization proved to be independent of BMP-4. gp130/Xstat3 stimulation inhibited Smad2-induced ectopic axis formation in embryos and Smad2-dependent luciferase activity. A dominant-negative Stat3, in contrast, dorsalized Xenopus embryos, resulting in ectopic axis formation. We propose that Stat3-mediated signaling has the capacity to modify dorsoventral patterning in the early development of Xenopus.
Nishinakamura
R
R
Department of Stem Cell Regulation, University of Tokyo, Japan.
Matsumoto
Y
Y
Matsuda
T
T
Ariizumi
T
T
Heike
T
T
Asashima
M
M
Yokota
T
T
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D019521:Body Patterning; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000378:metabolism*; D002460:Cell Line; D050822:Cytokine Receptor gp130; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D006651:Histocytochemistry; D017403:In Situ Hybridization; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008845:Microinjections; D009024:Morphogenesis; D012333:RNA, Messenger / Q000378:metabolism; D050796:STAT3 Transcription Factor; D015398:Signal Transduction; D051899:Smad2 Protein; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014981:Xenopus / Q000196:embryology*; D029867:Xenopus Proteins
D015703:Antigens, CD; C525809:BMP4 protein, human; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D004268:DNA-Binding Proteins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D050796:STAT3 Transcription Factor; D051899:Smad2 Protein; C497785:Smad2 protein, Xenopus; D015534:Trans-Activators; D029867:Xenopus Proteins; C525812:bmp4 protein, Xenopus; D050822:Cytokine Receptor gp130