Molecular factors controlling the interaction between two cell recycling systems

Chaperone-mediated autophagy (CMA) and endosomal microautophagy (eMI) share a compensatory relationship in degrading cytosolic proteins.

• Both CMA and eMI recognize the same five-amino-acid motif in substrate proteins.
• The chaperone protein Bag6 plays a role in sorting and internalizing eMI substrates into late endosomes.
• Starvation affects the dynamics of Bag6 at the late endosome membrane and is associated with a decline in eMI activity.
• A coordinated function between CMA and eMI suggests that these pathways may interchangeably degrade specific subsets of proteins.

Simplified