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Large nucleotide-dependent movement of the N-terminal domain of the ClpX chaperone.

ABSTRACT: The ClpXP ATPase-protease complex is a major component of the protein quality control machinery in the cell. A ClpX subunit consists of an N-terminal zinc binding domain (ZBD) and a C-terminal AAA+ domain. ClpX oligomerizes into a hexamer with the AAA+ domains forming the base of the hexamer and the ZBDs extending out of the base. Here, we report that ClpX switches between a capture and a feeding conformation. ZBDs in ClpX undergo large nucleotide-dependent block movement towards ClpP and into the AAA+ ring. This motion is modulated by the ClpX cofactor, SspB. Evidence for this movement was initially obtained by the surprising observation that an N-terminal extension on ClpX is clipped by bound ClpP in functional ClpXP complexes. Protease-protection, crosslinking, and light scattering experiments further support these findings.

SUBMITTER: Thibault G

PROVIDER: S-EPMC1523177 | biostudies-literature | 2006 Jul

REPOSITORIES: biostudies-literature

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Large nucleotide-dependent movement of the N-terminal domain of the ClpX chaperone.

Thibault Guillaume G Tsitrin Yulia Y Davidson Toni T Gribun Anna A Houry Walid A WA

The EMBO journal 20060629 14

The ClpXP ATPase-protease complex is a major component of the protein quality control machinery in the cell. A ClpX subunit consists of an N-terminal zinc binding domain (ZBD) and a C-terminal AAA+ domain. ClpX oligomerizes into a hexamer with the AAA+ domains forming the base of the hexamer and the ZBDs extending out of the base. Here, we report that ClpX switches between a capture and a feeding conformation. ZBDs in ClpX undergo large nucleotide-dependent block movement towards ClpP and into t ...[more]

PMID: 16810315

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