HOG1 MAPK参与调控亚砷酸钠诱导的酵母细胞凋亡

Involvement of HOG1 MAPK in the regulation of sodium arsenite-induced apoptosis in yeast cells

【目的】本研究探讨了HOG1 MAPK在亚砷酸钠诱导酵母细胞凋亡中的作用。【方法】以酵母野生株BY4741及其HOG1突变株(ΔHOG1)为材料,研究了亚砷酸钠对酵母细胞生长、相对存活率和氧化损伤的影响,并采用流式细胞术检测了亚砷酸钠胁迫下酵母细胞凋亡率、ROS水平和线粒体膜电位的变化。【结果】亚砷酸钠可抑制酵母细胞生长,诱导细胞凋亡。在相同处理组中,ΔHOG1对亚砷酸钠更为敏感,表现为细胞存活率降低,凋亡率升高。在亚砷酸钠胁迫过程中,ΔHOG1胞内ROS水平和MDA含量显著高于野生株BY4741,而线粒体膜电位显著低于野生株。【结论】HOG1 MAPK可能通过影响胞内ROS水平和线粒体膜电位的变化调控亚砷酸钠诱导的酵母细胞凋亡。

[Objective] In this study, we studied the role of HOG1 MAPK in sodium arsenite-induced apoptosis in yeast cells.[Methods] Yeast wild-type(BY4741) and HOG1 mutant(ΔHOG1) strains were used to study the effects of sodium arsenite on the growth and relative survival rate and oxidative damages of yeast cells. Further, the apoptotic rate, intracellular reactive oxygen species(ROS) level, and mitochondrial membrane potential of the yeast cells under sodium arsenite-induced stress were determined by flow cytometry.[Results] Sodium arsenite inhibited the growth of yeast cells and induced their apoptosis. Compared to the wild-type strain in the same treatment group,ΔHOG1 strain showed higher sensitivity to sodium arsenite with a lower cell survival rate and higher apoptotic rate. Under sodium arsenite-induced stress,ΔHOG1 strain showed significantly higher intracellular ROS and malondialdehyde(MDA) levels than the wild-type BY4741 strain. On the contrary, the mitochondrial membrane potential of ΔHOG1 strain was significantly lower than that of the wild-type BY4741 strain.[Conclusion] These results indicated that HOG1 MAPK gene was involved in the regulation of sodium arsenite-induced apoptosis by affecting intracellular ROS level and changing ?ψM in yeast cells.