RRC ID 53592
著者 Chen YC, Li CL, Hsiao YY, Duh Y, Yuan HS.
タイトル Structure and function of TatD exonuclease in DNA repair.
ジャーナル Nucleic Acids Res
Abstract TatD is an evolutionarily conserved protein with thousands of homologues in all kingdoms of life. It has been suggested that TatD participates in DNA fragmentation during apoptosis in eukaryotic cells. However, the cellular functions and biochemical properties of TatD in bacterial and non-apoptotic eukaryotic cells remain elusive. Here we show that Escherichia coli TatD is a Mg(2+)-dependent 3'-5' exonuclease that prefers to digest single-stranded DNA and RNA. TatD-knockout cells are less resistant to the DNA damaging agent hydrogen peroxide, and TatD can remove damaged deaminated nucleotides from a DNA chain, suggesting that it may play a role in the H2O2-induced DNA repair. The crystal structure of the apo-form TatD and TatD bound to a single-stranded three-nucleotide DNA was determined by X-ray diffraction methods at a resolution of 2.0 and 2.9 Å, respectively. TatD has a TIM-barrel fold and the single-stranded DNA is bound at the loop region on the top of the barrel. Mutational studies further identify important conserved metal ion-binding and catalytic residues in the TatD active site for DNA hydrolysis. We thus conclude that TatD is a new class of TIM-barrel 3'-5' exonuclease that not only degrades chromosomal DNA during apoptosis but also processes single-stranded DNA during DNA repair.
巻・号 42(16)
ページ 10776-85
公開日 2014-1-1
DOI 10.1093/nar/gku732
PII gku732
PMID 25114049
PMC PMC4176340
MeSH Catalytic Domain DNA / chemistry DNA / metabolism DNA Repair* DNA Repair Enzymes / chemistry* DNA Repair Enzymes / metabolism Escherichia coli / enzymology* Escherichia coli Proteins / chemistry* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism Exodeoxyribonucleases / chemistry* Exodeoxyribonucleases / metabolism Exonucleases / chemistry* Exonucleases / genetics Magnesium / metabolism Models, Molecular RNA / metabolism Sequence Alignment
IF 11.502
引用数 8
リソース情報
原核生物(大腸菌)