Mitotic phosphorylation-induced dissociation of GTSE1 from microtubule plus ends

Starting in mitotic prometaphase, GTSE1 becomes phosphorylated at threonine residues T513 and T526 (and possibly other sites), located adjacent to the two SKIP-like motifs involved in binding to MAPRE1 (EB1). Mitotic phosphorylation of GTSE1 inhibits its association with microtubule plus ends. CDK1 activity inhibits the association of recombinant human GTSE1 with microtubule plus ends in Xenopus extracts, but it is not certain whether CDK1 or another mitotic kinase phosphorylates GTSE1 (Scolz et al. 2012).自有丝分裂前期开始，GTSE1蛋白在苏氨酸残基T513和T526（以及可能的其他位点）发生磷酸化，这些位点毗邻参与与MAPRE1（EB1）结合的SKIP样基序。GTSE1的有丝分裂磷酸化作用抑制了其与微管正端的结合。CDK1活性可抑制重组人GTSE1与非洲爪蟾提取物中的微管正端结合，但尚不能确定是CDK1还是另一种有丝分裂激酶对GTSE1进行磷酸化（Scolz等，2012年）。