EXCISION OF DEOXYRIBOSE PHOSPHATE RESIDUES BY DNA-POLYMERASE-BETA DURING DNA-REPAIR
EXCISION OF DEOXYRIBOSE PHOSPHATE RESIDUES BY DNA-POLYMERASE-BETA DURING DNA-REPAIR
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DOI：
10.1126/science.7624801
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发表时间：
1995-08-04
期刊：
影响因子：
56.9
通讯作者：
KIM, K
中科院分区：
文献类型：
--
作者：
MATSUMOTO, Y;KIM, K
真核DNA聚合酶β（pol β）可以在碱基切除DNA修复过程中催化DNA合成。这里显示，pol β还催化从切割的脱嘌呤-脱嘧啶位点释放5 '末端脱氧核糖磷酸（dRP）残基，其是碱基切除修复中的常见中间产物。该活性的催化结构域位于pol β的氨基末端8千道尔顿片段内，其包含酶的不同结构域。镁是从双链DNA释放dRP所必需的，但不是从单链寡核苷酸释放dRP所必需的。对释放产物的分析表明，切除反应通过β-消除而不是水解发生。
Eukaryotic DNA polymerase beta (pol beta) can catalyze DNA synthesis during base excision DNA repair. It is shown here that pol beta also catalyzes release of 5'-terminal deoxyribose phosphate (dRP) residues from incised apurinic-apyrimidinic sites, which are common intermediate products in base excision repair. The catalytic domain for this activity resides within an amino-terminal 8-kilodalton fragment of pol beta, which comprises a distinct structural domain of the enzyme. Magnesium is required for the release of dRP from double-stranded DNA but not from a single-stranded oligonucleotide. Analysis of the released products indicates that the excision reaction occurs by beta-elimination rather than hydrolysis.