FIGURE 4.

Lysosomal-mediated degradation of mitochondria. (A) Mitochondria are labeled by the E3 ubiquitin ligase Parkin for mitochondrial autophagy (mitophagy) or removal by endosomes. Engulfment of ubiquinated cargo involves autophagy adaptors such as p62/SQSTM1 which link ubiquinated cargo to the autophagosome through LC3/GABARAP interaction. Outer mitochondrial membrane mitophagy receptors BNIP3, BNIPL3L/NIX, and FUNDC1 facilitate the degradation of whole organelles through direct interaction with LC3/GABARAP. (B) Mitochondria can be directly taken up by the lysosome, engulfed by single-membraned endosomes or double-membraned autophagosomes which fuse with the lysosome for the degradation of cargo.