Kaushal Kamini, Antao Ainsley Mike, Das Soumyadip, Kim Sammy L, Birappa Girish, Rajkumar Sripriya, Gowda D A Ayush, Ajaykumar C Bindu, Singh Vijai, Kim Keesung, Suresh Bharathi, Ramakrishna Suresh
Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea.
Department of Biological Sciences, College of Sang-Huh Life Science, Konkuk University, Seoul 05029, Korea.
BMB Rep. 2025 Aug;58(8):350-356. doi: 10.5483/BMBRep.2024-0154.
Aurora B is a widely studied mitotic checkpoint kinase that forms a part of the chromosomal passenger complex. The entry to and exit from mitosis are exquisitely controlled by Aurora B proteins, which regulate mitotic phases including chromosomal condensation, segregation, and cytokinesis, ensuring faithful propagation of daughter cells. Abnormal regulation of Aurora B proteins during the cell cycle can cause increased chromosomal segregation errors and ultimately lead to cancer. Thus, it is important to understand the key mechanisms that can modulate Aurora B protein levels during the cell cycle. Therefore, in this study we demonstrated the role of Ubiquitin-specific protease 7 (USP7) in regulating Aurora B protein level. Aurora B protein levels are upregulated when USP7 is dose-dependently increased, and downregulated when USP7 is depleted. By co-immunoprecipitation and Duolink assays, we demonstrated that USP7 interact with Aurora B. Furthermore, by treating cycloheximide we showed that USP7 extends the Aurora B protein half-life by its deubiquitinating activity. Finally, CRISPR/Cas9-mediated USP7 knockout produces severe nuclear structural defects causing multi-nucleation and cytokinesis failures, suggesting that the important role of USP7 during mitotic progression in stabilizing Aurora B. [BMB Reports 2025; 58(8): 350-356].
极光激酶B（Aurora B）是一种被广泛研究的有丝分裂检查点激酶，它是染色体乘客复合体的一部分。有丝分裂的进入和退出由极光激酶B蛋白精确控制，该蛋白调节有丝分裂阶段，包括染色体凝聚、分离和胞质分裂，确保子细胞的忠实增殖。细胞周期中极光激酶B蛋白的异常调节会导致染色体分离错误增加，最终导致癌症。因此，了解在细胞周期中可以调节极光激酶B蛋白水平的关键机制非常重要。因此，在本研究中，我们证明了泛素特异性蛋白酶7（USP7）在调节极光激酶B蛋白水平中的作用。当USP7剂量依赖性增加时，极光激酶B蛋白水平上调，而当USP7缺失时则下调。通过免疫共沉淀和Duolink检测，我们证明了USP7与极光激酶B相互作用。此外，通过用放线菌酮处理，我们表明USP7通过其去泛素化活性延长了极光激酶B蛋白的半衰期。最后，CRISPR/Cas9介导的USP7基因敲除产生严重的核结构缺陷，导致多核化和胞质分裂失败，这表明USP7在有丝分裂进程中对稳定极光激酶B具有重要作用。[《BMB报告》2025年；58(8): 350 - 356]
