Use of inducible Atg5 deletion and expression cell lines in study of the pro-survival function of autophagy under starvation.
Use of inducible Atg5 deletion and expression cell lines in study of the pro-survival function of autophagy under starvation.
复制标题
DOI：
10.1016/j.bbrc.2012.08.117
复制
发表时间：
2012-10
影响因子：
3.1
通讯作者：
Bo Chen;Xiangjie Sun;Yin Zhang;Xinqiang Zhu;Han-Ming Shen
中科院分区：
文献类型：
--
作者：
Bo Chen;Xiangjie Sun;Yin Zhang;Xinqiang Zhu;Han-Ming Shen
目前，自噬在细胞死亡和细胞存活中的作用仍然存在争议，部分原因是敲除不同自噬相关基因（Atg）的永生化小鼠胚胎成纤维细胞（mef）的结果相互矛盾。在这里，我们旨在重新审视自噬在饥饿和其他应激条件下细胞死亡中的作用。首先，Atg5敲除mef的不同克隆对应激介导的细胞死亡具有不同的易感性，这表明是克隆变异，而不是Atg5缺失或自噬本身决定了易感性。接下来，我们对两种诱导Atg5缺失或表达的细胞系进行了测试，结果表明，不表达Atg5的细胞对饥饿诱导的凋亡更敏感。最后，我们发现氯喹只对表达atg5的细胞致敏饥饿诱导的细胞死亡有效，而对缺乏atg5的细胞无效。因此，这些观察结果为支持饥饿下自噬的促生存功能提供了明确的证据。此外，我们的数据表明，诱导缺失或表达Atg的细胞在细胞死亡和细胞存活中的自噬研究中是有用的。
At present the role of autophagy in cell death and cell survival remains controversial, partly owning to the contradictory results from the immortalized mouse embryonic fibroblasts (MEFs) with knockout of different autophagy-related genes (Atg). Here we aimed to reexamine the role of autophagy in cell death under starvation and other stress conditions. First, different clones of Atg5 knockout MEFs had different susceptibility to stress-mediated cell death, indicating that it is the clonal variation, rather than the deficiency of Atg5 or autophagy per se that determines the susceptibility. Next, we tested two cell lines with inducible Atg5 deletion or expression and demonstrated that cells without Atg5 expression were more sensitive to starvation-induced apoptosis. Finally, we found that chloroquine was only effective in sensitizing starvation-induced cell death in Atg5-expressing cells, but not in Atg5-deficient cells. Such observations thus provide unequivocal evidence supporting the pro-survival function of autophagy under starvation. Moreover, our data demonstrate the usefulness of cells with inducible deletion or expression of Atg in the study of autophagy in cell death and cell survival.