Dataset Information

Crystal structure of the human CNOT6L nuclease domain reveals strict poly(A) substrate specificity.

ABSTRACT: CCR4, an evolutionarily conserved member of the CCR4-NOT complex, is the main cytoplasmic deadenylase. It contains a C-terminal nuclease domain with homology to the endonuclease-exonuclease-phosphatase (EEP) family of enzymes. We have determined the high-resolution three-dimensional structure of the nuclease domain of CNOT6L, a human homologue of CCR4, by X-ray crystallography using the single-wavelength anomalous dispersion method. This first structure of a deadenylase belonging to the EEP family adopts a complete alpha/beta sandwich fold typical of hydrolases with highly conserved active site residues similar to APE1. The active site of CNOT6L should recognize the RNA substrate through its negatively charged surface. In vitro deadenylase assays confirm the critical active site residues and show that the nuclease domain of CNOT6L exhibits full Mg(2+)-dependent deadenylase activity with strict poly(A) RNA substrate specificity. To understand the structural basis for poly(A) RNA substrate binding, crystal structures of the CNOT6L nuclease domain have also been determined in complex with AMP and poly(A) DNA. The resulting structures suggest a molecular deadenylase mechanism involving a pentacovalent phosphate transition.

SUBMITTER: Wang H

PROVIDER: S-EPMC2928688 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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Crystal structure of the human CNOT6L nuclease domain reveals strict poly(A) substrate specificity.

Wang Hui H Morita Masahiro M Yang Xiuna X Suzuki Toru T Yang Wen W Wang Jiao J Ito Kentaro K Wang Quan Q Zhao Cong C Bartlam Mark M Yamamoto Tadashi T Rao Zihe Z

The EMBO journal 20100713 15

CCR4, an evolutionarily conserved member of the CCR4-NOT complex, is the main cytoplasmic deadenylase. It contains a C-terminal nuclease domain with homology to the endonuclease-exonuclease-phosphatase (EEP) family of enzymes. We have determined the high-resolution three-dimensional structure of the nuclease domain of CNOT6L, a human homologue of CCR4, by X-ray crystallography using the single-wavelength anomalous dispersion method. This first structure of a deadenylase belonging to the EEP fami ...[more]

PMID: 20628353

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Dataset Information

Crystal structure of the human CNOT6L nuclease domain reveals strict poly(A) substrate specificity.

Publications

Crystal structure of the human CNOT6L nuclease domain reveals strict poly(A) substrate specificity.

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