Activation of PKC isozymes involves their translocation to specific subcellular compartments where they can interact with substrates. This process is regulated by binding proteins, such as the protein interacting with C kinase 1 (PICK1),168 which localizes PKC at AMPA receptors, and by the Receptors for Activated C Kinase (RACKs), two of which have been cloned: RACK1 which binds activated PKCβII169 and εRACK (β′COP) which binds activated PKCε.170
