since the studies on tyrosine phosphorylation of calmodulin by the insulin receptor kinase in vitro suggested that protamine and poly ( l-lysine ) may activate phosphorylation of the receptor beta subunit [ sacks & mcdonald ( 1988 ) j. biol . chem . 263 , 2377-2383 ] , we examined the effects of a variety of basic polycations/proteins and polyamines on insulin receptor kinase activity .
C0031715
phosphorylation
C0031727
kinase