Tsimokha Anna S, Mittenberg Alexey G, Kulichkova Valentina A, Kozhukharova Irina V, Gause Larisa N, Konstantinova Irina M
Laboratory of Regulation of Gene Expression, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Ave, 4, St. Petersburg 194064, Russia.
Cell Biol Int. 2007 Apr;31(4):338-48. doi: 10.1016/j.cellbi.2007.01.018. Epub 2007 Jan 21.
Changes in the subunit composition, phosphorylation of the subunits, and regulation of the activities of 26S proteasomes in proliferating cells undergoing programmed cell death have not been studied so far. Moreover, there are no reports on phosphorylation of proteasome subunits both in normal and in neoplastic cells during apoptosis. The data of the present study show for the first time that apoptosis inductor doxorubicin regulates subunit composition, enzymatic activities, and phosphorylation state of 26S proteasomes in neoplastic (proerythroleukemic K562) cells or, in other words, induces reprogramming of proteasome population. Furthermore, the phosphorylation state of proteasomes is found to be the mechanism controlling specificity of proteasomal proteolytic and endoribonuclease activities.
迄今为止，尚未对经历程序性细胞死亡的增殖细胞中26S蛋白酶体的亚基组成变化、亚基磷酸化以及活性调节进行研究。此外，目前尚无关于正常细胞和肿瘤细胞在凋亡过程中蛋白酶体亚基磷酸化的报道。本研究数据首次表明，凋亡诱导剂阿霉素可调节肿瘤细胞（红白血病K562细胞）中26S蛋白酶体的亚基组成、酶活性和磷酸化状态，或者换句话说，可诱导蛋白酶体群体的重编程。此外，发现蛋白酶体的磷酸化状态是控制蛋白酶体蛋白水解和核糖核酸内切酶活性特异性的机制。
