Dataset Information

Crystal structure of the protein from Arabidopsis thaliana gene At5g06450, a putative DnaQ-like exonuclease domain-containing protein with homohexameric assembly.

ABSTRACT: Arabidopsis thaliana gene At5g06450 encodes a putative DnaQ-like 3'-5' exonuclease domain-containing protein (AtDECP). The DnaQ-like 3'-5' exonuclease domain is often found as a proofreading domain of DNA polymerases. The overall structure of AtDECP adopts an RNase H fold that consists of a mixed ?-sheet flanked by ?-helices. Interestingly, AtDECP forms a homohexameric assembly with a central six fold symmetry, generating a central cavity. The ring-shaped structure and comparison with WRN-exo, the best structural homologue of AtDECP, suggest a possible mechanism for implementing its exonuclease activity using positively charged patch on the N-terminal side of the homohexameric assembly. The homohexameric structure of AtDECP provides unique information about the interaction between the DnaQ-like 3'-5' exonuclease and its substrate nucleic acids.

SUBMITTER: Smith DW

PROVIDER: S-EPMC4435538 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Crystal structure of the protein from Arabidopsis thaliana gene At5g06450, a putative DnaQ-like exonuclease domain-containing protein with homohexameric assembly.

Smith David W DW Han Mi Ra MR Park Joon Sung JS Kim Kyung Rok KR Yeom Taeho T Lee Ji Yeon JY Kim Do Jin DJ Bingman Craig A CA Kim Hyun-Jung HJ Jo Kyubong K Han Byung Woo BW Phillips George N GN

Proteins 20130617 9

Arabidopsis thaliana gene At5g06450 encodes a putative DnaQ-like 3'-5' exonuclease domain-containing protein (AtDECP). The DnaQ-like 3'-5' exonuclease domain is often found as a proofreading domain of DNA polymerases. The overall structure of AtDECP adopts an RNase H fold that consists of a mixed β-sheet flanked by α-helices. Interestingly, AtDECP forms a homohexameric assembly with a central six fold symmetry, generating a central cavity. The ring-shaped structure and comparison with WRN-exo, t ...[more]

PMID: 23616405

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Dataset Information

Crystal structure of the protein from Arabidopsis thaliana gene At5g06450, a putative DnaQ-like exonuclease domain-containing protein with homohexameric assembly.

Publications

Crystal structure of the protein from Arabidopsis thaliana gene At5g06450, a putative DnaQ-like exonuclease domain-containing protein with homohexameric assembly.

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