PLK2
Description
The PLK2 (polo like kinase 2) is a protein-coding gene located on chromosome 5.
Serine/threonine-protein kinase PLK2 is an enzyme that in humans is encoded by the PLK2 gene. Serum-inducible kinase is a member of the 'polo' family of serine/threonine protein kinases that have a role in normal cell division.
PLK2, also known as Polo-like kinase 2, is a tumor suppressor serine/threonine-protein kinase involved in synaptic plasticity, centriole duplication, and G1/S phase transition. Polo-like kinases, including PLK2, act by binding and phosphorylating proteins that are already phosphorylated on a specific motif recognized by the POLO box domains. PLK2 phosphorylates several proteins, including CENPJ, NPM1, RAPGEF2, RASGRF1, SNCA, SIPA1L1, and SYNGAP1. PLK2 plays a key role in synaptic plasticity and memory by regulating the Ras and Rap protein signaling pathways. It is required for overactivity-dependent spine remodeling by phosphorylating the Ras activator RASGRF1 and the Rap inhibitor SIPA1L1, leading to their degradation by the proteasome. Conversely, PLK2 phosphorylates the Rap activator RAPGEF2 and the Ras inhibitor SYNGAP1, promoting their activity. PLK2 also regulates synaptic plasticity independently of its kinase activity, through its interaction with NSF. This interaction disrupts the interaction between NSF and the GRIA2 subunit of AMPARs, leading to a rapid rundown of AMPAR-mediated current that occludes long-term depression. PLK2 is required for procentriole formation and centriole duplication by phosphorylating CENPJ and NPM1, respectively. Its induction by p53/TP53 suggests that it may participate in the mitotic checkpoint following stress.
PLK2 is also known as SNK, hPlk2, hSNK.
