pretreatment of ncb-20 cells with a calcium ionophore , a23187 , gave increased phosphorylation of the 90- and 130-kda proteins , but phorbol esters such as 12-o-tetradecanoylphorbol 13-acetate ( tumor promoting agent ) , cell depolarization with high k+ , or pretreatment with dibutyryl cyclic gmp had no effect on phosphorylation of these proteins .
C0031586
phorbol esters
C0039654
12-o-tetradecanoylphorbol 13-acetate