Different activities of the frizzled-related proteins frzb2 and sizzled2 during Xenopus anteroposterior patterning.
In a search for factors that regulate patterning of the Xenopus anteroposterior (A/P) axis, particularly the anterior ectoderm, we isolated two members of the Frizzled-related protein (FRP) gene family that are thought to encode antagonists of Wnt signaling. frzb2 is expressed in head mesoderm while sizzled2 is expressed in ventral ectoderm and mesoderm, tissues that modulate anterior fates. Consistent with a role for these genes in A/P patterning, ectopically expressed frzb2 inhibited head formation, while sizzled2 dorsalized embryos, causing expansion of the head. The different activities of frzb2 and sizzled2 may be explained by their interaction with distinct proteins since frzb2 is an inhibitor of Xwnt8 activity, while sizzled2 is unable to inhibit the activity of Xwnt8 or any other Xwnt tested. The data suggest that anteroposterior patterning is modulated by multiple components of the Wnt signaling pathway.
Bradley
L
L
Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, 02142, USA.
Sun
B
B
Collins-Racie
L
L
LaVallie
E
E
McCoy
J
J
Sive
H
H
D000595:Amino Acid Sequence; D000818:Animals; D019521:Body Patterning; D019556:COS Cells; D002454:Cell Differentiation; D003001:Cloning, Molecular; D004475:Ectoderm / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D008648:Mesoderm / Q000378:metabolism; D008969:Molecular Sequence Data; D009132:Muscles / Q000166:cytology / Q000196:embryology; D010641:Phenotype; D010802:Phylogeny; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D015398:Signal Transduction; D014162:Transfection; D051153:Wnt Proteins; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins
D011506:Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D051153:Wnt Proteins; D029867:Xenopus Proteins; D029961:Zebrafish Proteins; C491629:frzb2 protein, Xenopus; C109976:szl protein, Xenopus