Suppressor of cytokine signaling (SOCS)-5 is a potential negative regulator of epidermal growth factor signaling

Abstract

The suppressors of cytokine signaling (SOCS) proteins are a family of SH2 domain-containing intracellular inhibitors of cytokine signal transduction that act by several different mechanisms. Recent evidence suggests that the action of the SOCS proteins may extend beyond the cytokine receptors to signaling initiated by members of the tyrosine kinase receptor family. In this study, the ability of SOCS-5 to negatively regulate signaling cascades downstream of the epidermal growth factor receptor (EGF-R) has been examined by using an EGF-responsive cell line engineered to constitutive express the EGF-R and SOCS-5 or SOCS-5 mutants. SOCS-5 associated with the EGF-R complex in an EGF-independent m..