Direct metabolic regulation of beta-catenin activity by the p85alpha regulatory subunit of phosphoinositide 3-OH kinase.
Class IA phosphoinositide 3-OH kinases ( PI3K) are lipid kinases composed of catalytic and regulatory subunits. These lipid kinases can regulate the metabolic stability and signaling activity of beta-catenin, a central component of the E-cadherin/catenin cell-cell adhesion complex, and of the Wnt signaling pathway. This regulation occurs at the level of glycogen synthase kinase 3 (GSK3), a serine/threonine kinase that marks beta-catenin to enter a destruction pathway. In addition, the regulatory subunit p85alpha directly binds beta-catenin, but the role of this interaction in the context of the lipid kinase regulation of beta-catenin signaling is unknown. Here we report that expression of exogenous p85alpha in mouse keratinocytes increases the metabolic stability and has a strong synergistic effect on the transcriptional activity of beta-catenin. Both effects are associated to the formation of beta-catenin/p85alpha and inhibition of beta-catenin/APC complexes and are independent of GSK3 and PI3K activities. These findings suggest that p85alpha can act as a direct metabolic regulator of beta-catenin activity.[1]References
- Direct metabolic regulation of beta-catenin activity by the p85alpha regulatory subunit of phosphoinositide 3-OH kinase. Espada, J., Peinado, H., Esteller, M., Cano, A. Exp. Cell Res. (2005) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
