hnRNP A2/B1在人永生化表皮HaCaT细胞凋亡过程中的表达及其调控作用研究

The Expression of hnRNP A2/B1 and Regulation during the Apoptosis in Human Immortalized Epidermal HaCaT Cells Induced by Curcumin

该文以姜黄素诱导人永生化表皮HaCaT细胞凋亡为基础,对hnRNP A2/B1在核基质中的存在、分布及其与细胞凋亡相关基因产物的共定位及相互作用关系进行了研究。蛋白质印迹结果显示,hnRNP A2/B1存在于HaCaT细胞核基质蛋白组分中,在经过姜黄素处理后,表达下调;激光共聚焦显微镜观察显示,hnRNP A2/B1在HaCaT细胞中分别与Fas、p53和Bax等基因产物具有共定位关系,姜黄素处理后其共定位区域出现由核膜或核仁向胞质转移的趋势。GST pull-down实验证实,hnRNPA2/B1分别与Fas、p53和Bax有直接相互作用关系。结果表明,hnRNPA2/B1作为一种核基质蛋白,通过与细胞凋亡相关基因产物的相互作用参与HaCaT细胞的凋亡诱导调控过程,这对深入认识核基质蛋白在细胞凋亡过程中的调控机制具有重要意义。

This paper explore the existence and distribution of hnRNP A2/B 1 in nuclear matrix, and the colocalization relationship between hnRNP A2/B 1 and the products of some apoptosis interrelated genes in the human immortalized epidermal HaCaT cells before and after curcumin treatment. It was confirmed by Western blot that hnRNP A2/B 1 existed in the component of nuclear matrix protein of HaCaT cells and its expression was decreased by curcumin treatment. The co-localization between hnRNP A2/B 1 and the products of apoptosis interrelated genes including Fas, p53 and Bax were observed by using laser scanning confocal microscopy. The recombinant protein was expressed and purified after building a prokaryotic expression vector pGEX-4T-2-hnRNP A2/B 1, and GST pull-down assay confirmed that hnRNP A2/B1 directly interacted with Fas, p53 and Bax, respectively. The results of this study demonstrated that hnRNP A2/B 1 was a nuclear matrix protein and locacted in the nuclear matrix, and the distribution of hnRNP A2/B1 and its relationship with associated gene products play important role during the apoptosis of HaCaT cells, which had great significance in in-depth understanding of regulatory mechanisms of nuclear matrix proteins in apoptosis.