Phosphorylation of pp60v-src by the TPA receptor kinase (protein kinase C)

Incubation of pp60v-src with the purified 12-O-tetradecanoyl-13-acetate (TPA) receptor kinase (protein kinase C) resulted in an increase in the phosphorylation of pp60v-src. Two-dimensional tryptic phosphopeptide mapping showed that three major phosphoserine containing peptides were labeled which were localized within the amino terminal 18,000 Da of the src protein. Based on comparative tryptic mapping, one of these major phosphopeptides was identical to the peptide labeled on pp60v-src immunoprecipitated from cells labeled with [32P]orthophosphate and treated with TPA. These data suggest that a direct interaction takes place between protein kinase C and pp60v-src.