PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. This subfamily is composed of the dual-specificity kinase Myt1, the protein tyrosine kinase Wee1, and similar proteins. These proteins are cell cycle checkpoint kinases that are involved in the regulation of cyclin-dependent kinase CDK1, the master engine for mitosis. CDK1 is kept inactivated through phosphorylation of N-terminal thr (T14 by Myt1) and tyr (Y15 by Myt1 and Wee1) residues. Mitosis progression is ensured through activation of CDK1 by dephoshorylation and inactivation of Myt1/Wee1. The Wee1-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein serine/threonine PKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.
Jiyao W et al.(2023). "The conserved domain database in 2023.",