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Crystal structure of the human mitochondrial chaperonin symmetrical football complex.

ABSTRACT: Human mitochondria harbor a single type I chaperonin system that is generally thought to function via a unique single-ring intermediate. To date, no crystal structure has been published for any mammalian type I chaperonin complex. In this study, we describe the crystal structure of a football-shaped, double-ring human mitochondrial chaperonin complex at 3.15 Å, which is a novel intermediate, likely representing the complex in an early stage of dissociation. Interestingly, the mitochondrial chaperonin was captured in a state that exhibits subunit asymmetry within the rings and nucleotide symmetry between the rings. Moreover, the chaperonin tetradecamers show a different interring subunit arrangement when compared to GroEL. Our findings suggest that the mitochondrial chaperonins use a mechanism that is distinct from the mechanism of the well-studied Escherichia coli system.

SUBMITTER: Nisemblat S

PROVIDER: S-EPMC4434751 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Crystal structure of the human mitochondrial chaperonin symmetrical football complex.

Nisemblat Shahar S Yaniv Oren O Parnas Avital A Frolow Felix F Azem Abdussalam A

Proceedings of the National Academy of Sciences of the United States of America 20150427 19

Human mitochondria harbor a single type I chaperonin system that is generally thought to function via a unique single-ring intermediate. To date, no crystal structure has been published for any mammalian type I chaperonin complex. In this study, we describe the crystal structure of a football-shaped, double-ring human mitochondrial chaperonin complex at 3.15 Å, which is a novel intermediate, likely representing the complex in an early stage of dissociation. Interestingly, the mitochondrial chape ...[more]

PMID: 25918392

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