Microautophagy: definition, classification, and the complexity of the underlying mechanisms

ATG, autophagy related; e-MI, endosomal microautophagy; ER, endoplasmic reticulum; ESCRT, endosomal sorting complex required for transport; EV, extracellular vesicle; HSPA8/HSC70, heat shock protein family A (Hsp70) member 8; ILVs, intralumenal vesicles; l-MI, lysosomal microautophagy; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MCOLN1, mucolipin TRP cation channel 1; microautophagy, MI-autophagy; MVBs, multivesicular bodies; SQSTM1, sequestosome 1; v-MI, vacuolar microautophagy.