Figure 1.

Schematic representation of the three main types of autophagy. Macroautophagy involves the sequestration of the cargo inside a double membrane vesicle—the autophagosome—followed by its fusion with the lysosomes (a). In microautophagy, an invagination of the lysosomal membrane occurs into which the substrate is engulfed (b). Chaperone-mediated autophagy (CMA) is a selective type of autophagy in which a protein bearing the KFERQ motif is recognised by the cytosolic chaperone Hsc70 and its co-chaperone complex. The complex is then targeted to LAMP-2A on the lysosomal membrane where it will unfold and translocate into the lysosome (c).