Catalytic domain of the Serine/Threonine Kinase, PCTAIRE-2 kinase
STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PCTAIRE-2 is specifically expressed in neurons in the central nervous system, mainly in terminally differentiated neurons. It associates with Trap (Tudor repeat associator with PCTAIRE-2) and could play a role in regulating mitochondrial function in neurons. PCTAIRE-2 shares sequence similarity with Cyclin-Dependent Kinases (CDKs), which belong to a large family of STKs that are regulated by their cognate cyclins. Together, CDKs and cyclins are involved in the control of cell-cycle progression, transcription, and neuronal function. The PCTAIRE-2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.