Regulatory Autophosphorylation Sites on Protein Kinase C-δ at Threonine-141 and Threonine-295

摘要: Protein kinase C-δ (PKCδ) is a Ser/Thr that regulates wide range of cellular responses. This study identifies novel in vitro PKCδ autophosphorylation sites at Thr141 adjacent to the pseudosubstrate domain, Thr218 C1A-C1B interdomain, Ser295, Ser302, and Ser304 hinge region, Ser503 Thr505 activation loop. Cell-based studies show Thr295 also are phosphorylated vivo phosphorylation kinetics downregulation COS7 cells. In implicate as modifications regulate activity. A T141D substitution markedly increases basal lipid-independent activity; PKCδ-T141D mutant only slightly further stimulated by PMA treatment, suggesting relieves autoinhibitory constraints limit Mutagenesis indicate contributes control substrate specific...