hDaxx高表达抑制地塞米松诱导的HeLa细胞凋亡

目的利用真核表达载体pEGFP/hDaxx在HeLa细胞中高表达hDaxx,研究hDaxx对HeLa细胞凋亡的影响.方法将pEGFP/hDaxx转染HeLa细胞,Western-blotting鉴定GFP-hDaxx融合蛋白的表达,荧光显微镜观察GFP-hDaxx融合蛋白在细胞内的表达及定位,用地塞米松诱导HeLa细胞凋亡,细胞用Giemsa染色后,观察细胞形态变化并计算HeLa细胞凋亡率.结果GFP-hDaxx融合蛋白在HeLa细胞中成功表达并定位于细胞核.地塞米松对照组与pEGFP对照组凋亡率无显著性差异(P＞0.05),而pEGFP/hDaxx组凋亡率显著降低(P＜0.01),即hDaxx即时高表达降低地塞米松诱导的HeLa细胞凋亡率.结论Daxx为调控蛋白,GFP-hDaxx融合蛋白在HeLa细胞中表达并定位于细胞核,且hDaxx即时高表达抑制地塞米松诱导的HeLa细胞凋亡.

The Overexpression of hDaxx Inhibits Apoptosis Induced by Dexamethasone in HeLa Cells

Objective To study the effects from overexpression of hDaxx on Dexamethasone-induced apoptosis in HeLa cells. Methods An eukaryotic expression vector pEGFP/hDaxx was used to transfect HeLa cells for overexpressing hDaxx. HeLa cells were respectively transfected with pEGFP/hDaxx and pEGFP, and the expression was identified by Western-blot. Furtherly, under fluorescent microscope the expression and localization of GFP-hDaxx fusion protein in HeLa cells was observed. Then, dexamethasone was added to HeLa cells medium for inducing apoptosis, the apoptosis rate of HeLa cells in morphology was counted by Giemsa stain and the difference between the cells transfected by pEGFP and that by pEGFP/hDaxx was analyzed. Results GFP-hDaxx fusion protein was ideally expressed in HeLa cells and localized in nuclei under fluorescent microscope, and GFP-hDaxx fusion protein was identified by Western-blot. Besides, there was a remarkable difference between pEGFP/hDaxx group and dexamethasone control group and pEGFP control group(P<0.01), but no remarkable difference between dexamethasone control group and pEGFP control group(P>0.05), all of which indicated transient overexpression of hDaxx decreased dexamethasone-induced apoptosis rate of HeLa cells. Conclusion Daxx is a regulatory protein in nuclei, GFP-hDaxx fusion protein is expressed in HeLa cells and localized in nuclei, and transient overexpression of hDaxx inhibits dexamethasone-induced apoptosis in HeLa cells.