Polo-Box Domain

**Semantic type:** Amino Acid Sequence

**Definition:** Members of the polo subfamily of protein kinases appear to play pivotal roles in cell division and proliferation. These include mammalian Plk, Snk, and Fnk/Prk, Xenopus laevis Plx1, Drosophila melanogaster polo, Schizosaccharomyces pombe Plo1, and Saccharomyces cerevisiae Cdc5. The polo family members are characterized by the presence of a distinct region of homology in the C-terminal non-catalytic domain, termed the polo-box, which is essential for subcellular localization and mitotic functions of the polo kinases. Regulation of polo kinases may be crucial in the control of cell division.