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Structure of the nuclease domain of ribonuclease III from M. tuberculosis at 2.1 A.

ABSTRACT: RNase III enzymes are a highly conserved family of proteins that specifically cleave double-stranded (ds)RNA. These proteins are involved in a diverse group of functions, including ribosomal RNA processing, mRNA maturation and decay, snRNA and snoRNA processing, and RNA interference. Here we report the crystal structure of the nuclease domain of RNase III from the pathogen Mycobacterium tuberculosis. Although globally similar to other RNase III folds, this structure has some features not observed in previously reported models. These include the presence of an additional metal ion near the catalytic site, as well as conserved secondary structural elements that are proposed to have functional roles in the recognition of dsRNAs.

SUBMITTER: Akey DL

PROVIDER: S-EPMC2253305 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature

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Structure of the nuclease domain of ribonuclease III from M. tuberculosis at 2.1 A.

Akey David L DL Berger James M JM

Protein science : a publication of the Protein Society 20050909 10

RNase III enzymes are a highly conserved family of proteins that specifically cleave double-stranded (ds)RNA. These proteins are involved in a diverse group of functions, including ribosomal RNA processing, mRNA maturation and decay, snRNA and snoRNA processing, and RNA interference. Here we report the crystal structure of the nuclease domain of RNase III from the pathogen Mycobacterium tuberculosis. Although globally similar to other RNase III folds, this structure has some features not observe ...[more]

PMID: 16155207

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