Syntide-2 is a synthetic peptide recognized as a substrate by Ca2+/calmodulin-dependent protein kinase II (CaMKII; Km = 12 μM). Its sequence is derived from the phosphorylation site 2 on glycogen synthase, a target of CaMKII action. This peptide has been used as a probe to assay CaMKII activity; however, protein kinase C, CaMKV, Raf-1, and other kinases are also known to recognize syntide-2 as a substrate.
