The substrates and binding partners of protein kinase Cε

The ε isoform of protein kinase C (PKCε) has important roles in the function of the cardiac, immune and nervous systems. As a result of its diverse actions, PKCε is the target of active drug-discovery programmes. A major research focus is to identify signalling cascades that include PKCε and the substrates that PKCε regulates. In the present review, we identify and discuss those proteins that have been conclusively shown to be direct substrates of PKCε by the best currently available means. We will also describe binding partners that anchor PKCε near its substrates. We review the consequences of substrate phosphorylation and discuss cellular mechanisms by which target specificity is achieved. We begin with a brief overview of the biology of PKCε and methods for substrate identification, and proceed with a discussion of substrate categories to identify common themes that emerge and how these may be used to guide future studies.