Activation of protein kinase C δ by the c-Abl tyrosine kinase in response to ionizing radiation

The c-Abl protein tyrosine kinase is activated by ionizing radiation (IR) and certain other DNA-damaging agents. The present studies demonstrate that c-Abl associates constitutively with protein kinase C δ (PKCδ). The results show that the SH3 domain of c-Abl interacts directly with PKCδ. c-Abl phosphorylates and activates PKCδ in vitro. We also show that IR treatment of cells is associated with c-Abl-dependent phosphorylation of PKCδ and translocation of PKCδ to the nucleus. These findings support a functional interaction between c-Abl and PKCδ in the cellular response to genotoxic stress.