Fig. 1
From: The nuclear receptor 4A family members: mediators in human disease and autophagy
The three main types of autophagy in mammalian cells. Microautophagy: small pieces of the cytoplasm are directly engulfed by lysosomal or late endosomal membranes. Chaperone-mediated autophagy (CMA): unfolded proteins are directly transported across the lysosomal membrane. Macroautophagy: Cytosolic double-membrane autophagosomes form to sequester and transport cargo to the lysosome