Ca2+/CaM-dependent kinases:: From activation to function

Calmodulin (CaM) is an essential protein that serves as a ubiquitous intracellular receptor for Ca2+. The Ca2+/CaM complex initiates a plethora of signaling cascades that culminate in alteration of cellular functions. Among the many Ca2+/CaM-binding proteins to be discovered. the multifunctional protein kinases CaMKI, II, and IV play pivotal roles. Our review focuses on this class of CaM kinases to illustrate the structural and biochemical basis for Ca2+/CaM interaction with and regulation of its target enzymes. Gene transcription has been chosen as the functional endpoint to illustrate the recent advances in Ca2+/CaM-mediated signal transduction mechanisms.