Before we have reported lamprey PHB2 could enhance the cellular oxidative-stressed tolerance, here the aim was to explore its mechanisms. We used flow cytometry analysis to identify a Lampetra morii homologue of PHB2 (Lm-PHB2) that could significantly decrease the levels of ROS generation in HEK293T cells. According to confocal microscopy observations, Lm-PHB2 contributed to maintain the mitochondrial morphology of HEK293T cells, and then both cellular nuclear location and translocation from the nucleus to mitochondria of Lm-PHB2 were also examined in HEK293T cells under oxidative stress. We also examined the expressions and locations of various Lm-PHB2 deletion mutants and the amino acid mutant by confocal microscopy and the results showed that the translocation of Lm-PHB2 into mitochondria was dependent on the Lm-PHB2_1-50aa region and the 17th, 48th and 57th three arginines (R) of N-terminal were very critical. In addition, the analyses of QRT-PCR and Western blot demonstrated that Lm-PHB2 increased the expression levels of OPA1 and HAX1 in HEK293T cells treated with H₂O₂. The analyses of immunofluorescence and immunoprecipitation showed that Lm-PHB2 could interact with OPA1 and HAX1, respectively. The above mentioned results indicate that Lm-PHB2 could assist OPA1 and HAX1 to maintain mitochondrial morphology and decrease ROS levels by the translocation from the nucleus to mitochondria under oxidative stress.

在我们报道七lamp鳗PHB2可以增强细胞氧化应激耐受性之前，这里的目的是探索其机理。我们使用流式细胞仪分析来鉴定兰佩特兰PHB2（Lm-PHB2）的同系物，可以显着降低HEK293T细胞中ROS的产生水平。根据共聚焦显微镜观察，Lm-PHB2有助于维持HEK293T细胞的线粒体形态，然后在氧化应激下，还检查了HEK293T细胞中Lm-PHB2的细胞核定位和从核向线粒体的移位。我们还通过共聚焦显微镜检查了各种Lm-PHB2缺失突变体和氨基酸突变体的表达和位置，结果表明Lm-PHB2进入线粒体的转运取决于Lm-PHB2 _1-50aa该区域以及N末端的第17、48和57个三个精氨酸（R）非常关键。另外，QRT-PCR和蛋白质印迹的分析表明，Lm-PHB2增加了用H ₂ O ₂处理的HEK293T细胞中OPA1和HAX1的表达水平。免疫荧光和免疫沉淀分析表明，Lm-PHB2可以分别与OPA1和HAX1相互作用。上述结果表明，Lm-PHB2在氧化应激下可通过从核向线粒体的易位而协助OPA1和HAX1维持线粒体形态并降低ROS水平。