Bridging of b-catenin and glycogen synthase kinase-3b by Axin and inhibition of b-catenin-mediated transcription
نویسندگان
چکیده
Axin antagonizes the developmental effects of Wnt in vertebrates. We show here that Axin simultaneously binds two components of the Wnt pathway, b-catenin and its negative regulator glycogen synthase kinase-3b. In mammalian cells, Axin inhibits Wnt-1 stimulation of b-cateniny lymphoid enhancer factor 1-dependent transcription. Axin also blocks b-catenin-mediated transcription in colon cancer cells that have a mutation in the adenomatous polyposis coli gene. These findings suggest that Axin, by forming a complex with b-catenin and glycogen synthase kinase-3b, can block signaling stimulated by Wnt or by adenomatous polyposis coli
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