NEK9 is a 107 kD member of the serine/threonine-protein kinase family, NIMA subfamily containing a coiled-coil domain, and RCC1 repeats. This cytoplasmic protein forms dimers and is a pleiotropic regulator of mitotic progression, participating in the control of spindle dynamics and chromosome separation, Nek9 is activated during mitosis by intramolecular autophosphorylation at Thr210. Nek9 has been shown to interact with Ran GTPase (greater affinity for Ran-GDP over Ran-GTP), NEK6, NEK7, BICD2, histone H3, myelin basic protein, and beta-casein. The Poly6241 antibody recognizes human NEK9 and has been shown to be useful for Western blotting, immunohistochemistry, and immunoprecipitation.