Lysosomal microautophagy: an emerging dimension in mammalian autophagy

Trends Cell Biol. 2023 Dec 15:S0962-8924(23)00238-6. doi: 10.1016/j.tcb.2023.11.005. Online ahead of print.ABSTRACTAutophagy is a self-catabolic process through which cellular components are delivered to lysosomes for degradation. There are three types of autophagy, i.e., macroautophagy, chaperone-mediated autophagy (CMA), and microautophagy. In macroautophagy, a portion of the cytoplasm is wrapped by the autophagosome, which then fuses with lysosomes and delivers the engulfed cytoplasm for degradation. In CMA, the translocation of cytosolic substrates to the lysosomal lumen is directly across the limiting membrane of lysosomes. In microautophagy, lytic organelles, including endosomes or lysosomes, take up a portion of the cytoplasm directly. Although macroautophagy has been investigated extensively, microautophagy has received much less attention. Nonetheless, it has become evident that microautophagy plays a variety of cellular roles from yeast to mammals. Here we review the very recent updates of microautophagy. In particular, we focus on the feature of the degradative substrates and the molecular machinery that mediates microautophagy.PMID:38104013 | DOI:10.1016/j.tcb.2023.11.005
Source: Trends in Cell Biology - Category: Cytology Authors: Source Type: research