Jurkat细胞增殖过程中S期激酶相关蛋白2与p27kip1的表达变化及意义

目的 探讨S期激酶相关蛋白2(Skp2)与p27kip1在淋巴瘤细胞株Jurkat细胞增殖过程中的表达变化及意义.方法 采用免疫沉淀法检测Jurkat细胞中p27kip1与Skp2的结合情况;采用血清饥饿合并释放法同步化处理Jurkat细胞,再分别用Western blot技术、免疫荧光双标技术及核浆分离法检测p27kip1和Skp2在Jurkat细胞中的表达变化及亚细胞定位.结果 p27kip1与Skp2能够相互结合.在Jurkat细胞增殖过程中,p27kip1蛋白表达减少,其中在细胞核内的减少更明显;Skp2蛋白表达增加,其中在细胞浆中的增加更明显.结论 在Jurkat细胞增殖过程中,Skp2在细胞浆中的合成增加,并可能通过加快p27kip1的泛素化降解使细胞核内p27kip1显著减少,从而推动细胞周期的进程.

Expression variation and significance of Skp2 and p27(kip1) during the proliferation of Jurkat cells

Objective To investigate the expression variation and significance of Skp2 and p27kip1 during the proliferation of lymphoma cell line Jurkat cells. Methods The binding of p27kip1 and Skp2 in Jurkat cells were detected by immunoprecipitation. Jurkat cells were treated with serum starvation and release synchronization. The expression variation and subcellular localization of p27kip1 and Skp2 were detected by subcellular fractionation, Western blot and double immunofluorescence labelling. Results The results of immunoprecipitation suggested that p27kip1 and Skp2 could bind each other in Jurkat cells. During the proliferation of Jurkat cells, the protein expression of p27kip1 decreased and intranuclear p27kip1 decreased significantly, while the Skp2 protein increased and cytoplasmic Skp2 increased significantly. Conclusion During the proliferation of Jurkat cells, the increased cytoplasmic synthesis of Skp2 may speed up p27kip1 degradation via the ubiquitin-proteasome pathway, then intranuclear p27kip1 decreases significantly, leading to an increased cell cycling activity.