Visualization of Sparsely-populated Lower-order Oligomeric States of Human Mitochondrial Hsp60 by Cryo-electron Microscopy.

ABSTRACT: Human mitochondrial Hsp60 (mtHsp60) is a class I chaperonin, 51% identical in sequence to the prototypical E. coli chaperonin GroEL. mtHsp60 maintains the proteome within the mitochondrion and is associated with various neurodegenerative diseases and cancers. The oligomeric assembly of mtHsp60 into heptameric ring structures that enclose a folding chamber only occurs upon addition of ATP and is significantly more labile than that of GroEL, where the only oligomeric species is a tetradecamer. The lability of the mtHsp60 heptamer provides an opportunity to detect and visualize lower-order oligomeric states that may represent intermediates along the assembly/disassembly pathway. Using cryo-electron microscopy we show that, in addition to the fully-formed heptamer and an "inverted" tetradecame

SUBMITTER: Walti MA 

PROVIDER: S-EPMC8627483 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature