Control of beta-catenin phosphorylation/degradation by a dual-kinase mechanism.
Article Details
- CitationCopy to clipboard
Liu C, Li Y, Semenov M, Han C, Baeg GH, Tan Y, Zhang Z, Lin X, He X
Control of beta-catenin phosphorylation/degradation by a dual-kinase mechanism.
Cell. 2002 Mar 22;108(6):837-47.
- PubMed ID
- 11955436 [ View in PubMed]
- Abstract
Wnt regulation of beta-catenin degradation is essential for development and carcinogenesis. beta-catenin degradation is initiated upon amino-terminal serine/threonine phosphorylation, which is believed to be performed by glycogen synthase kinase-3 (GSK-3) in complex with tumor suppressor proteins Axin and adnomatous polyposis coli (APC). Here we describe another Axin-associated kinase, whose phosphorylation of beta-catenin precedes and is required for subsequent GSK-3 phosphorylation of beta-catenin. This "priming" kinase is casein kinase Ialpha (CKIalpha). Depletion of CKIalpha inhibits beta-catenin phosphorylation and degradation and causes abnormal embryogenesis associated with excessive Wnt/beta-catenin signaling. Our study uncovers distinct roles and steps of beta-catenin phosphorylation, identifies CKIalpha as a component in Wnt/beta-catenin signaling, and has implications to pathogenesis/therapeutics of human cancers and diabetes.