PLK1
PLK1 (polo like kinase 1, also known as PLK) is a serine/threonine-protein kinase that performs several key functions throughout M phase of the cell cycle. It governs centrosome maturation, spindle assembly, chromosome segregation and cytokinesis. Browse Assay Genie's current range of PLK1 research reagents below, or read on for the biology behind the target.
PLK1 acts throughout mitosis. It regulates centrosome maturation and spindle assembly, the removal of cohesins from chromosome arms, the inactivation of anaphase-promoting complex/cyclosome (APC/C) inhibitors, and mitotic exit and cytokinesis. Polo-like kinases bind and phosphorylate proteins that are already phosphorylated on a specific motif recognised by the POLO box domains. PLK1 can also create its own docking sites, for example on PRC1 and KIF20A/MKLP2, by phosphorylating the sites that its POLO box domains then recognise.
At the G2/M transition, PLK1 phosphorylates CCNB1, CDC25C, FOXM1, PKMYT1/MYT1 and WEE1. It is part of a circuit that promotes CDK1 activation by phosphorylating the positive regulator CDC25C and inhibiting the negative regulators WEE1 and PKMYT1. At the centrosome, phosphorylation of NEDD1 promotes targeting of the gamma-tubulin ring complex, an important step in spindle formation. In cytokinesis, phosphorylation of RACGAP1 creates a docking site for the Rho GTP exchange factor ECT2, which is essential for cleavage furrow formation. PLK1 is also high on unattached kinetochores, suggesting a role in kinetochore attachment or spindle assembly checkpoint regulation.
Further substrates link PLK1 to DNA repair (POLQ and RHNO1), heat shock signalling (HSF1) and ciliary protein localisation (DZIP1). It acts as a negative regulator of p53 family members, phosphorylating TOPORS and the transactivation domain of p73/TP73. During meiosis I it works with MEIKIN to regulate kinetochore function. The PLK1 gene belongs to the CDC5/Polo subfamily of the Ser/Thr protein kinase family, and the former name was polo-like kinase (Drosophila). The protein is highly expressed during mitosis and elevated in many types of cancer. Depleting it in cancer cells inhibits proliferation and induces apoptosis, which makes it a target for cancer therapy.
PLK1 regulates centrosome maturation, spindle assembly, the G2/M transition, mitotic exit and cytokinesis, making it a central subject in M phase research.
PLK1 levels are elevated in many types of cancer, and its depletion inhibits cancer cell proliferation and induces apoptosis.
PLK1 acts at kinetochores and in cohesin removal, with roles in spindle assembly checkpoint regulation and meiosis I kinetochore function.
PLK1 is needed for recovery from DNA damage checkpoints, regulates POLQ recruitment, and negatively regulates p53 and p73.
PLK1 is a serine/threonine kinase that acts throughout M phase. It regulates centrosome maturation, spindle assembly, cohesin removal from chromosome arms, the G2/M transition, mitotic exit and cytokinesis by phosphorylating substrates such as CDC25C, WEE1, NEDD1 and RACGAP1.
The HGNC name is polo like kinase 1, and PLK is a listed alias. The UniProt name is serine/threonine-protein kinase PLK1. Earlier names include polo-like kinase (Drosophila). PLK1 belongs to the CDC5/Polo subfamily and is a member of the polo like kinase family, which also includes PLK2.
NCBI Gene reports that PLK1 is highly expressed in mitosis and elevated in many cancers, and that depleting it in cancer cells inhibits proliferation and induces apoptosis. Mouse and rat both have a Plk1 ortholog; check the datasheet of any product for its validated reactivity.
Another member of the polo like kinase family, with related reagents for cell cycle and mitosis research.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P53350; product specifications from Assay Genie datasheets.