A conserved family of serine/threonine kinases (Plks) that have a C-terminal Polo-box domain (PBD) and an N-terminal kinase domain. There are four human Plks, (Plk1 (603 aa); Plk2 (685 aa), serum-inducible kinase, Snk; Plk3 (646 aa), cytokine-inducible kinase, proliferation-related kinase, Prk; Plk4 (970 aa), homologue of mouse Sak, although some species have fewer, as is the case for polo in Drosophila, mutations in which cause aberrant spindle pole behaviour. Plks are important in centriole duplication. See protein kinase N.
Subjects: Medicine and Health.