Wnt signalling: What the X at the # is WTX?

Abstract

In this issue of The EMBO Journal, Tanneberger et al demonstrate that Amer1/WTX, a tumour suppressor protein previously known for promoting β-catenin degradation and thus antagonizing Wnt signalling, is also required for LRP6 receptor phosphorylation and therefore activation of Wnt signalling. Amer1/WTX is recruited by PtdIns(4,5)P2 to the plasma membrane, and in turn recruits the Axin-GSK3 complex and CK1γ to phosphorylate LRP6. While dichotomic players like Amer1/WTX are common in Wnt signalling, these new findings add more intrigues to this enigmatic protein and pathway. © 2011 European Molecular Biology Organization | All Rights Reserved.