Myosin phosphatase dephosphorylates PLK1

The myosin phosphatase complex can dephosphorylate PLK1 threonine residue T210 and inactivate PLK1 (Yamashiro et al. 2008). Myosin phosphatase is activated through phosphorylation of its PPP1R12A (MYPT1) subunit. Several kinases, including CDK1 (Yamashiro et al. 2008) and LATS1 (Chiyoda et al. 2012) have been implicated in myosin phosphatase activation, but the position and temporal order of key PPP1R12A phosphorylations need to be investigated further. Phosphorylated OPTN (optineurin) is able to bind PPP1R12A (MYPT1) and positively regulates PLK1 dephosphorylation by myosin phosphatase, posibly by facilitating PPP1R12A phosphorylation and myosin phosphatase activation (Kachaner et al. 2012).

肌球蛋白磷酸酶复合物可去磷酸化PLK1苏氨酸残基T210，从而失活PLK1（Yamashiro等，2008年）。肌球蛋白磷酸酶通过其PPP1R12A（MYPT1）亚基的磷酸化而被激活。包括CDK1（Yamashiro等，2008年）和LATS1（Chiyoda等，2012年）在内的多种激酶已被涉及肌球蛋白磷酸酶的激活，但关键PPP1R12A磷酸化的位置和时序尚需进一步研究。磷酸化的OPTN（optineurin）能够与PPP1R12A（MYPT1）结合，并通过正向调控肌球蛋白磷酸酶介导的PLK1去磷酸化，可能通过促进PPP1R12A磷酸化和肌球蛋白磷酸酶的激活来实现（Kachaner等，2012年）。