Cheon Yeongmi, Lee Soojin
Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon, South Korea.
FASEB J. 2018 Jun 4:fj201701358RRR. doi: 10.1096/fj.201701358RRR.
Skp, Cullin, F-box (SCF) ubiquitin ligases play a central role in cell cycle regulation and tumorigenesis via proteolytic cleavage of many essential cell cycle regulators. In this study, we propose that centromere protein (CENP)-W, a newly identified kinetochore component, is a novel negative regulator of the SCF complex. CENP-W interacts with Cullin (CUL)-1 and β-Transducin repeat-containing protein (β-TrCP)-1 through highly overlapped binding sites with S-phase kinase-associated protein (SKP)-1. CENP-W is incorporated into the SCF complex to promote complex disassembly. Unlike other known regulators that increase SCF ubiquitin ligase activity by promoting complex reassociation, CENP-W-mediated complex disorganization induced β-TrCP1 degradation and consequently decreased its activity. The association between CENP-W and the SCF complex was prominent during the G/M transition in the nucleus. Especially, CENP-W knockdown decreased the cell division cycle-25A protein level, leading to a delay in mitotic progression. We propose that CENP-W participates in cell cycle regulation by modulating SCF ubiquitin ligase activity.-Cheon, Y., Lee, S. CENP-W inhibits CDC25A degradation by destabilizing the SCF complex at G/M.
Skp、Cullin、F-box(SCF)泛素连接酶通过对许多重要细胞周期调节因子进行蛋白水解切割,在细胞周期调控和肿瘤发生中发挥核心作用。在本研究中,我们提出着丝粒蛋白(CENP)-W,一种新鉴定的动粒成分,是SCF复合物的新型负调节因子。CENP-W通过与S期激酶相关蛋白(SKP)-1高度重叠的结合位点,与Cullin(CUL)-1和含β-转导蛋白重复序列的蛋白(β-TrCP)-1相互作用。CENP-W被纳入SCF复合物以促进复合物解体。与其他通过促进复合物重新结合来增加SCF泛素连接酶活性的已知调节因子不同,CENP-W介导的复合物解体诱导β-TrCP1降解,从而降低其活性。CENP-W与SCF复合物之间的关联在细胞核的G/M转换期间最为显著。特别是,CENP-W敲低降低了细胞分裂周期蛋白25A的水平,导致有丝分裂进程延迟。我们提出CENP-W通过调节SCF泛素连接酶活性参与细胞周期调控。——Cheon, Y., Lee, S. CENP-W在G/M期通过破坏SCF复合物的稳定性抑制CDC25A降解