GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com


Jump to: navigation, search


You don't have sufficient rights on this wiki to edit tables. Perhaps you need to log in. Changes you make in the Table editor will not be saved back to the wiki

See Help for Help on this wiki. See the documentation for how to use the table editor


Luo, W, Peterson, A, Garcia, BA, Coombs, G, Kofahl, B, Heinrich, R, Shabanowitz, J, Hunt, DF, Yost, HJ and Virshup, DM (2007) Protein phosphatase 1 regulates assembly and function of the beta-catenin degradation complex. EMBO J. 26:1511-21


The Wnt/beta-catenin signaling pathway is critical in both cellular proliferation and organismal development. However, how the beta-catenin degradation complex is inhibited upon Wnt activation remains unclear. Using a directed RNAi screen we find that protein phosphatase 1 (PP1), a ubiquitous serine/threonine phosphatase, is a novel potent positive physiologic regulator of the Wnt/beta-catenin signaling pathway. PP1 expression synergistically activates, and inhibition of PP1 inhibits, Wnt/beta-catenin signaling in Drosophila and mammalian cells as well as in Xenopus embryos. The data suggest that PP1 controls Wnt signaling through interaction with, and regulated dephosphorylation of, axin. Inhibition of PP1 leads to enhanced phosphorylation of specific sites on axin by casein kinase I. Axin phosphorylation markedly enhances the binding of glycogen synthase kinase 3, leading to a more active beta-catenin destruction complex. Wnt-regulated changes in axin phosphorylation, mediated by PP1, may therefore determine beta-catenin transcriptional activity. Specific inhibition of PP1 in this pathway may offer therapeutic approaches to disorders with increased beta-catenin signaling.


PubMed PMC1829374 Online version:10.1038/sj.emboj.7601607


Animals; Armadillo Domain Proteins/metabolism; Axin Protein; Casein Kinase I/metabolism; Cell Line; DNA Primers; Drosophila; Drosophila Proteins/metabolism; Glycogen Synthase Kinase 3/metabolism; Humans; Immunoblotting; Immunoprecipitation; Mass Spectrometry; Mice; Mutagenesis; Phosphoprotein Phosphatases/genetics; Phosphoprotein Phosphatases/metabolism; Phosphorylation; Protein Phosphatase 1; RNA Interference; Repressor Proteins/metabolism; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction/physiology; Transcription Factors/metabolism; Wnt Proteins/metabolism; Xenopus; Xenopus Proteins