Regulation of Phospholipase C-γ1 by Profilin and Tyrosine Phosphorylation

• DOI: 10.1126/science.1848725
• Publication Date: 2006-10-05T18:10:16Z
• Authors: Pascal J. Goldsch...; Jae Won Kim; Laura M. Machesky; Sue Goo Rhee; Thomas D. Pollard
• Keywords: Profilin; Gq alpha subunit; Second messenger system

Epidermal growth factor and platelet-derived can stimulate the production of second messenger inositol trisphosphate in responsive cells, but biochemical pathway for these signaling events has been uncertain because reactions have not reconstituted with purified molecules vitro. A reconstitution is described that requires only factor, its receptor tyrosine kinase activity, soluble phospholipase C-γ1, also small actin-binding protein profilin. Profilin binds to substrate phosphatidylinositol 4,5-bisphosphate inhibits hydrolysis by unphosphorylated C-γ1. Phosphorylation C-γ1 epidermal overcomes inhibitory effect profilin results an effective activation