Regulation of cell apoptosis by protein kinase c δ

The isoforms of the PKC family are activated in response to mitogenic stimuli, to inflammatory stimuli, and to stress and play important roles in a variety of cellular functions including apoptosis. PKCδ a member of the novel PKC subfamily, is actively involved in cell apoptosis in a stimulus and tissue specific manner; it both regulates the expression and function of apoptotic related proteins and is itself a target for caspases. Activation of PKCδ by various apoptotic stimuli results in the translocation of PKCδ to distinct cellular compartments such as mitochondria, golgi and nucleus, and the differential translocation contributes to its different effects. In addition, phosphorylation of PKCδ on distinct tyrosine residues and its association with specific apoptotic related proteins such as c-Abl, DNA-PK, p73 and lamin B are pivotal to its function in cell apoptosis. Recent findings on these aspects of the PKCδ cascades are the major focus of this review.