Frzb-1 is a secreted antagonist of Wnt signaling expressed in the Spemann organizer.
Frzb-1 is a secreted protein containing a domain similar to the putative Wnt-binding region of the frizzled family of transmembrane receptors. Frzb-1 is widely expressed in adult mammalian tissues. In the Xenopus gastrula, it is expressed and regulated as a typical Spemann organizer component. Injection of frzb-1 mRNA blocks expression of XMyoD mRNA and leads to embryos with enlarged heads and shortened trunks. Frzb-1 antagonizes the effects of Xwnt-8 ectopic expression in a non-cell-autonomous manner. Cultured cells transfected with a membrane-tethered form of Wnt-1 bind epitope-tagged Frzb-1 in the 10(-10) M range. The results strengthen the view that the Spemann organizer is a source of secreted inhibitory factors.
Leyns
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Department of Biological Chemistry, University of California, Los Angeles 90095-1662, USA.
Bouwmeester
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Kim
S H
SH
Piccolo
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De Robertis
E M
EM
D000595:Amino Acid Sequence; D000818:Animals; D002450:Cell Communication / Q000502:physiology; D002478:Cells, Cultured / Q000502:physiology; D004627:Embryonic Induction / Q000502:physiology; D005775:Gastrula / Q000502:physiology; D006023:Glycoproteins; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007668:Kidney / Q000166:cytology; D008322:Mammals; D051379:Mice; D008934:Mitogens / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000196:embryology; D011485:Protein Binding / Q000502:physiology; D011506:Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D051153:Wnt Proteins; D051155:Wnt1 Protein; D014981:Xenopus / Q000196:embryology*; D029867:Xenopus Proteins; D029961:Zebrafish Proteins; D000099274:Frizzled-Related Proteins
D006023:Glycoproteins; D047908:Intracellular Signaling Peptides and Proteins; D008934:Mitogens; D011506:Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D051153:Wnt Proteins; D051155:Wnt1 Protein; D029867:Xenopus Proteins; D029961:Zebrafish Proteins; D000099274:Frizzled-Related Proteins; C495249:WNT1 protein, Xenopus; C495247:WNT1 protein, human; C495246:Wnt1 protein, mouse; C495248:wnt8a protein, Xenopus