Functional implications of assigned, assumed and assembled PKC structures

The empirical derivation of PKC (protein kinase C) domain structures and those modelled by homology or imputed from protein behaviour have been extraordinarily valuable both in the elucidation of PKC pathway mechanisms and in the general lessons that extrapolate to other signalling pathways. For PKC family members, there are many domain/subdomain structures and models, covering all of the known domains, variably present in this family of protein serine/threonine kinases (C1, C2, PB1, HR1, kinase domains). In addition to these structures, there are a limited number of complexes defined, including the structure of the PKCε V3–14-3-3 complex. In the context of structure-driven insights into PKC pathways, there are several broadly applicable principles and mechanisms relevant to the operation of and intervention in signalling pathways. These principles have an impact in unexpected ways, from the regulation of membrane targeting, through strategies for pharmacological intervention, to biomarkers.