| Phospholipase C gamma 1 is a guanine nucleotide exchange factor for dynamin 1 and enhances dynamin 1 dependent epidermal growth factor receptor endocytosis . ^^^ We demonstrate that PLC gamma 1 acts as a guanine nucleotide exchange factor ( GEF ) of dynamin 1 , a 100 kDa GTPase protein , which is involved in clathrin mediated endocytosis of epidermal growth factor ( EGF ) receptor . ^^^ Overexpression of PLC gamma 1 increases endocytosis of the EGF receptor by increasing guanine nucleotide exchange activity of dynamin 1 . ^^^ The GEF activity of PLC gamma 1 is mediated by the direct interaction of its SH 3 domain with dynamin 1 . ^^^ |