ABSTRACT

During macroautophagy/autophagy, autophagosomes fuse with lysosomes to form autolysosomes. After fusion, the autophagosome inner membrane and enclosed substrates are degraded and transported out of lysosomes for recycling. The lysosomal membrane components are recycled by autophagic lysosome reformation (ALR) to generate new lysosomes. However, the fate of autophagosome outer membrane components on autolysosomes remains unknown. Our recent work discovered that autophagosome outer membrane components are not degraded but are recycled through an unidentified process which we named autophagosomal components recycling (ACR). Further investigation revealed the recycler complex (SNX4-SNX5-SNX17) responsible for ACR. The discovery of ACR not only fills a missing part in autophagy, but also reveals a new recycling pathway on autolysosomes.

摘要

在巨自噬/自噬期间，自噬体与溶酶体融合形成自溶酶体。融合后，自噬体内膜和封闭的底物被降解并运出溶酶体进行回收。溶酶体膜成分通过自噬溶酶体重组 (ALR) 回收以产生新的溶酶体。然而，自噬溶酶体上自噬体外膜成分的命运仍然未知。我们最近的研究发现，自噬体外膜成分不会降解，而是通过我们命名为自噬体成分回收 (ACR) 的未知过程进行回收。进一步调查揭示了负责 ACR 的回收复合体 (SNX4-SNX5-SNX17)。ACR的发现不仅填补了自噬缺失的部分，而且揭示了自噬溶酶体的新循环途径。