In vitro substrate phosphorylation by Ca2+/calmodulin-dependent protein kinase kinase using guanosine-5′-triphosphate as a phosphate donor

摘要

BackgroundCa²⁺/calmodulin-dependent protein kinase kinase (CaMKK) phosphorylates and activates particular downstream protein kinases — including CaMKI, CaMKIV, and AMPK— to stimulate multiple Ca²⁺-signal transduction pathways. To identify previously unidentified CaMKK substrates, we used various nucleotides as phosphate donors to develop and characterize an in vitro phosphorylation assay for CaMKK.