Xiao Yuxuan, Lucas Benjamin, Molcho Elana, Schiff Tania, Vigodner Margarita
Department of Biology, Stern College, Yeshiva University, New York, NY, USA.
Department of Biology, Stern College, Yeshiva University, New York, NY, USA; Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA.
Biochem Biophys Res Commun. 2016 Sep 16;478(2):919-23. doi: 10.1016/j.bbrc.2016.08.051. Epub 2016 Aug 10.
Sumoylation (a covalent modification by Small Ubiquitin-like Modifiers or SUMO proteins) has been implicated in the regulation of various cellular events including cell cycle progression. We have recently identified CDK1, a master regulator of mitosis and meiosis, as a SUMO target both in vivo and in vitro, supporting growing evidence concerning a close cross talk between sumoylation and phosphorylation during cell cycle progression. However, any data regarding the effect of sumoylation upon CDK1 activity have been missing. In this study, we performed a series of in vitro experiments to inhibit sumoylation by three different means (ginkgolic acid, physiological levels of oxidative stress, and using an siRNA approach) and assessed the changes in CDK1 activity using specific antibodies and a kinase assay. We have also tested for an interaction between SUMO and active and/or inactive CDK1 isoforms in addition to having assessed the status of CDK1-interacting sumoylated proteins upon inhibition of sumoylation. Our data suggest that inhibition of sumoylation increases the activity of CDK1 probably through changes in sumoylated status and/or the ability of specific proteins to bind CDK1 and inhibit its activity.
SUMO化修饰（一种由小泛素样修饰蛋白或SUMO蛋白介导的共价修饰）参与调控包括细胞周期进程在内的多种细胞活动。我们最近发现，有丝分裂和减数分裂的主要调节因子CDK1在体内和体外均为SUMO的靶标，这进一步证明了在细胞周期进程中SUMO化修饰与磷酸化之间存在密切的相互作用。然而，关于SUMO化修饰对CDK1活性影响的相关数据尚属空白。在本研究中，我们进行了一系列体外实验，通过三种不同方法（银杏酸、生理水平的氧化应激以及RNA干扰）抑制SUMO化修饰，并使用特异性抗体和激酶分析评估CDK1活性的变化。除了评估SUMO化修饰被抑制后与CDK1相互作用的SUMO化蛋白的状态外，我们还检测了SUMO与活性和/或非活性CDK1亚型之间的相互作用。我们的数据表明，抑制SUMO化修饰可能通过改变SUMO化状态和/或特定蛋白结合CDK1并抑制其活性的能力来增加CDK1的活性。
