Base excision of oxidative purine and pyrimidine DNA damage in Saccharomyces cerevisiae by a DNA glycosylase with sequence similarity to endonuclease III from Escherichia coli
Base excision of oxidative purine and pyrimidine DNA damage in Saccharomyces cerevisiae by a DNA glycosylase with sequence similarity to endonuclease III from Escherichia coli
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DOI：
10.1073/pnas.93.20.10735
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发表时间：
1996-10-01
影响因子：
11.1
通讯作者：
Seeberg, E
中科院分区：
文献类型：
--
作者：
Eide, L;Bjoras, M;Seeberg, E
酿酒酵母（Saccharomycescerevisiae）染色体Ⅰ上的一个基因位点编码一个与大肠杆菌（Escherichia coli）DNA修复糖基化酶内切酶Ⅲ具有局部序列相似性的蛋白质（YAB 5_YEAST;登录号P31378）。杆菌NTG 1的靶向基因破坏产生了对H2 O2和甲萘醌敏感的突变体，表明NTG 1是体内DNA氧化损伤修复所必需的。对NTG 1-lacZ基因融合体的北方印迹分析和表达研究表明，NTG 1是由细胞暴露于不同的DNA损伤剂，特别是甲萘醌诱导的，因此属于S. cerevisiae，在E.在大肠杆菌中，NTG 1基因产物切割被四氧化锇破坏的质粒DNA，因此，表明对DNA中胸腺嘧啶二醇的特异性与EndoIII的情况类似。然而，NTG 1也释放甲醛嘧啶从DNA的高效率，因此，代表了一个糖基化酶与一个新的底物识别范围。与NTG 1类似的序列在其他真核生物中，包括秀丽隐杆线虫、粟酒裂殖酵母和哺乳动物中，最近已被录入GenBank，表明NTG 1类似基因在高等生物中普遍存在，S.酿酒酵母NTG 1不具有该家族其他成员所特有的[4Fe-4S]簇DNA结合结构域。
One gene locus on chromosome I in Saccharomyces cerevisiae encodes a protein (YAB5_YEAST; accession no, P31378) with local sequence similarity to the DNA repair glycosylase endonuclease III from Escherichia coli, We have analyzed the function of this gene, now assigned NTG1 (endonuclease three-like glycosylase 1), by cloning, mutant analysis, and gene expression in E. coli. Targeted gene disruption of NTG1 produces a mutant that is sensitive to H2O2 and menadione, indicating that NTG1 is required for repair of oxidative DNA damage in vivo, Northern blot analysis and expression studies of a NTG1-lacZ gene fusion showed that NTG1 is induced by cell exposure to different DNA damaging agents, particularly menadione, and hence belongs to the DNA damage-inducible regulon in S. cerevisiae, When expressed in E. coli, the NTG1 gene product cleaves plasmid DNA damaged by osmium tetroxide, thus, indicating specificity for thymine glycols in DNA similarly as is the case for EndoIII. However, NTG1 also releases formamidopyrimidines from DNA with high efficiency and, hence, represents a glycosylase with a novel range of substrate recognition. Sequences similar to NTG1 from other eukaryotes, including Caenorhabditis elegans, Schizosaccharomyces pombe, and mammals, have recently been entered in the GenBank suggesting the universal presence of NTG1-like genes in higher organisms, S. cerevisiae NTG1 does not have the [4Fe-4S] cluster DNA binding domain characteristic of the other members of this family.