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X-ray structure and activity of the yeast Pop2 protein: a nuclease subunit of the mRNA deadenylase complex.

ABSTRACT: In Saccharomyces cerevisiae, a large complex, known as the Ccr4-Not complex, containing two nucleases, is responsible for mRNA deadenylation. One of these nucleases is called Pop2 and has been identified by similarity with PARN, a human poly(A) nuclease. Here, we present the crystal structure of the nuclease domain of Pop2 at 2.3 A resolution. The domain has the fold of the DnaQ family and represents the first structure of an RNase from the DEDD superfamily. Despite the presence of two non-canonical residues in the active site, the domain displays RNase activity on a broad range of RNA substrates. Site-directed mutagenesis of active-site residues demonstrates the intrinsic ability of the Pop2 RNase D domain to digest RNA. This first structure of a nuclease involved in the 3'-5' deadenylation of mRNA in yeast provides information for the understanding of the mechanism by which the Ccr4-Not complex achieves its functions.

SUBMITTER: Thore S

PROVIDER: S-EPMC1326415 | biostudies-literature | 2003 Dec

REPOSITORIES: biostudies-literature

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X-ray structure and activity of the yeast Pop2 protein: a nuclease subunit of the mRNA deadenylase complex.

Thore Stéphane S Mauxion Fabienne F Séraphin Bertrand B Suck Dietrich D

EMBO reports 20031114 12

In Saccharomyces cerevisiae, a large complex, known as the Ccr4-Not complex, containing two nucleases, is responsible for mRNA deadenylation. One of these nucleases is called Pop2 and has been identified by similarity with PARN, a human poly(A) nuclease. Here, we present the crystal structure of the nuclease domain of Pop2 at 2.3 A resolution. The domain has the fold of the DnaQ family and represents the first structure of an RNase from the DEDD superfamily. Despite the presence of two non-canon ...[more]

PMID: 14618157

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