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The structural basis for regulated assembly and function of the transcriptional activator NtrC.

ABSTRACT: In two-component signal transduction, an input triggers phosphorylation of receiver domains that regulate the status of output modules. One such module is the AAA+ ATPase domain in bacterial enhancer-binding proteins that remodel the sigma(54) form of RNA polymerase. We report X-ray solution scattering and electron microscopy structures of the activated, full-length nitrogen-regulatory protein C (NtrC) showing a novel mechanism for regulation of AAA+ ATPase assembly via the juxtaposition of the receiver domains and ATPase ring. Accompanying the hydrolysis cycle that is required for transcriptional activation, we observed major order-disorder changes in the GAFTGA loops involved in sigma(54) binding, as well as in the DNA-binding domains.

SUBMITTER: De Carlo S

PROVIDER: S-EPMC1475761 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature

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The structural basis for regulated assembly and function of the transcriptional activator NtrC.

De Carlo Sacha S Chen Baoyu B Hoover Timothy R TR Kondrashkina Elena E Nogales Eva E Nixon B Tracy BT

Genes & development 20060601 11

In two-component signal transduction, an input triggers phosphorylation of receiver domains that regulate the status of output modules. One such module is the AAA+ ATPase domain in bacterial enhancer-binding proteins that remodel the sigma(54) form of RNA polymerase. We report X-ray solution scattering and electron microscopy structures of the activated, full-length nitrogen-regulatory protein C (NtrC) showing a novel mechanism for regulation of AAA+ ATPase assembly via the juxtaposition of the ...[more]

PMID: 16751184

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