Regulation of Smad Function by Phosphorylation

Abstract

Phosphorylation is a dynamic and reversible post-translational modification which has a strong impact on structural features of proteins. All Smad proteins have been reported as phosphoproteins. Phosphorylation of receptor-activated Smad proteins by type I receptors initiates TGF-β family signaling. Phosphorylation of Smads by a number of other kinases is a mechanism of cross-talk between Smads and other signaling pathways. Smad phosphorylation initiates a cascade of protein-protein and protein-DNA interactions, and affects localization of Smads. This chapter reviews the role of phosphorylation in Smad signaling