Dynamics of Autophagosome Formation
Autophagy, literally defined as “self-eating,” functions as a degradation process by recycling cytoplasmic contents under stress conditions or during development. Upon activation of autophagy, a membrane structure known as a phagophore forms and expands, finally closing to form a double-membrane vesicle called an autophagosome (Fig. 1; Lamb et al., 2013; Yin et al., 2016). The completed autophagosome, which contains the autophagic cargo, is delivered to the vacuole (plants and yeast) or lysosome (animals). The outer membrane fuses with the vacuolar/lysosomal membrane, and the inner membrane and contents are released into the vacuole/lysosome as an autophagic body and are degraded by hydrolases. The breakdown products are transported back into the cytoplasm for reuse by the cell (Yang and Bassham, 2015).
This article is published as Soto-Burgos J, Zhuang X, Jiang L, Bassham DC. Dynamics of Autophagosome Formation. Plant physiology. 2018; 176:219-229. doi: 10.1104/pp.17.01236. Copyright American Society of Plant Biologists. Posted with permission.