4.1.3. Hsp60

Hsp60 or chaperonins are 800–900 kDa double ring cylindrical complexes that originate in the mitochondria, but migrate to the cytosol under cellular stress. Cytosolic Hsp60 is also called TRiC or the TCP1 complex and usually has an 8-membered ring, whereas mitochondrial Hsp60 has a 7-membered ring modulated by a lid structure made of co-chaperone Hsp10. Client proteins enter the central cavity where the apical domain of Hsp60 exposes its hydrophobic residues for substrate binding. Following substrate binding, Hsp60 subunits undergo excessive conformational changes, ATP is hydrolyzed, and the folded protein is released through the Hsp10 lid [75,76].
