中文摘要：

细胞白噬是一类依赖于溶酶体的蛋白质降解途径，在真核生物中非常保守。自噬能够感受细胞所处环境的各种信号，如氨基酸、糖等营养物质的缺乏、pH值或渗透压的改变等，使细胞做出应激反应，在恶劣环境下存活。同时，自噬过程会清除细胞内错误折叠或聚集的蛋白质，受损或老化细胞器以维持细胞内部稳态。白噬发生时，细胞内部的胞质组分被包裹在自噬体中，自噬体与溶酶体融合进行降解，产生新的小分子，如氨基酸等供细胞重新利用。一系列研究发现自噬的信号通路非常复杂，已报道有40个自噬相关蛋白（Atg蛋白）参与了自噬体的形成过程。Atg蛋白按照一定步骤发挥功能，同时相互影响，利用内膜系统构建成一个闭合的双层膜结构。将对细胞自噬研究的历史、自噬分子机制的前沿进展进行综述。

英文摘要：

Autophagy is a conserved protein degradation process dependent on lysosome. Cells can sense various signals in the environment, such as amino acids, glucose or other nutrient deprivation, variation of pH or osmotic pressure to induce stress response and guarantee cell survival. Autophagy can maintain cell homeostasis by elimination of unfolded or aggregated proteins or damaged cell organelles. When autophagy occurs, autophagosome engulfs eytosolic components and fuses with lysosome for cargo degradation to produce recycling materials such as amino acids and lipids. Studies have shown that the signal mechanism of autophagy is very complicated and there are 40 autophagy related proteins （Atg） identified by now regulating the autophagy process. These proteins function step by step and interact with each other to build a double-membrane closed structure de novo from endomembrane system. In this review, we describe the history of research on autophagy and discuss the progression in autophagy regulation mechanism.