Catalytic domain of the Protein Serine/Threonine Kinase, Never In Mitosis gene A (NIMA)-related kinase 3
STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Nek3 is primarily localized in the cytoplasm and shows no cell cycle-dependent changes in its activity. It is present in the axons of neurons and affects morphogenesis and polarity through its regulation of microtubule acetylation. Nek3 modulates the signaling of the prolactin receptor through its activation of Vav2 and contributes to prolactin-mediated motility of breast cancer cells. It is one in a family of 11 different Neks (Nek1-11) that are involved in cell cycle control. The Nek family 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.