Cloning and sequencing a human homolog (hMYH) of the Escherichia coli mutY gene whose function is required for the repair of oxidative DNA damage

Slupska, Malgorzata M.; Baikalov, Claudia; Luther, Wendy M.; Chiang, Ju‐Huei; Wei, Yu-Ling; Miller, Jeffrey H

doi:10.1128/jb.178.13.3885-3892.1996

Cited by 357 publications

(231 citation statements)

References 20 publications

Supporting

Mentioning

221

Contrasting

Unclassified

Order By: Relevance

“…Furthermore, an activity that incises DNA containing 8-oxoG͞A mismatches has been partially purified from HeLa cells (42). A human homolog of the mutY gene of E. coli has been cloned, but no functional studies have been reported (43). Finally, a human homolog of the bacterial endonuclease III has been recently identified (26).…”

Section: Discussionmentioning

confidence: 99%

Cloning and characterization of hOGG1 , a human homolog of the OGG1 gene of Saccharomyces cerevisiae

Radicella

Dhérin

Desmaze

et al. 1997

Proc. Natl. Acad. Sci. U.S.A.

565

305

View full text Add to dashboard Cite

The OGG1 gene of Saccharomyces cerevisiae encodes a DNA glycosylase activity that is a functional analog of the Fpg protein from Escherichia coli and excises 7,8-dihydro-8-oxoguanine (8-oxoG) from damaged DNA. The repair of this ubiquitous kind of oxidative damage is essential to prevent mutations both in bacteria and in yeast. A human cDNA clone carrying an ORF displaying homology to the yeast protein was identified. The predicted protein has 345 amino acids and a molecular mass of 39 kDa. This protein shares a 38% sequence identity with the yeast Ogg1 protein, adding this novel human gene product to the growing family of enzymes that the repair of oxidatively damaged bases and are related to the E. coli endonuclease III. Northern blot analysis indicates that this gene, localized to chromosome 3p25, is ubiquitously expressed in human tissues. The cloned coding sequence was expressed in an E. coli strain that carried a disrupted fpg gene, the bacterial functional analog of OGG1. Cell-free extracts from these cultures displayed a specific lyase activity on duplex DNA that carried an 8-oxoG͞C base pair. The products of the reaction are consistent with an enzymatic activity like the one displayed by the yeast Ogg1. Analysis of the substrate specificity reveals a very strong preference for DNA fragments harboring 8-oxoG͞C base pairs. The pattern of specificity correlates well with the one found for the yeast enzyme. Moreover, when the human coding sequence was expressed in a yeast strain mutant in OGG1 it was able to complement the spontaneous mutator phenotype. These results make this novel gene (hOGG1) a strong candidate for the human homolog of the yeast OGG1 and suggest an important role of its product in the protection of the genome from the mutagenic effects of the oxidatively damaged purines.Reactive oxygen species (ROS) formed in cells either as by-products of aerobic metabolism or as a consequence of exposure to environmental mutagens can attack DNA or its precursors, yielding oxidatively damaged bases and strand breakage (1, 2). Unrepaired oxidative damage to DNA has been suggested to play a role in carcinogenesis and aging through mutations in genes controlling these biological processes (3-5). Several lines of evidence suggest that an oxidatively damaged form of guanine, 7,8-dihydro-8-oxoguanine (8-oxoG), is critical in terms of mutagenesis (6, 7). In Escherichia coli, two DNA glycosylases cooperate to prevent mutagenesis by 8-oxoG: the Fpg protein, which excises 8-oxoG in damaged DNA (8-10) and the MutY protein, which excises the adenine residues incorporated by DNA polymerases opposite 8-oxoG (11-13). Inactivation of both the fpg (mutM) and mutY (micA) genes of E. coli results in a strong G⅐C 3 T⅐A mutator phenotype (14-17).In Saccharomyces cerevisiae, the OGG1 gene encodes an 8-oxoG DNA glycosylase activity that reduces the mutator phenotype of the fpg mutY mutant of E. coli (18). The Ogg1 protein contains 376 amino acids, and, although it was cloned by functional complementation of the E. co...

show abstract

Section: Discussionmentioning

confidence: 99%

Cloning and characterization of hOGG1 , a human homolog of the OGG1 gene of Saccharomyces cerevisiae

Radicella

Dhérin

Desmaze

et al. 1997

Proc. Natl. Acad. Sci. U.S.A.

565

305

View full text Add to dashboard Cite

show abstract

“…Recently a human homologue (hMYH) with 41 % identity to the mutY gene was cloned and sequenced. The gene maps on the short arm of chromosome 1 between p32.1 and p34.3, contains 16 exons encoding 535 amino acids and is 7.1 kb long [105].…”

Section: G/t(u)-mismatch Dna Glycosylasesmentioning

confidence: 99%

DNA glycosylases in the base excision repair of DNA

Krokan

Standal

Slupphaug

1997

Biochemical Journal

771

566

View full text Add to dashboard Cite

A wide range of cytotoxic and mutagenic DNA bases are removed by different DNA glycosylases, which initiate the base excision repair pathway. DNA glycosylases cleave the Nglycosylic bond between the target base and deoxyribose, thus releasing a free base and leaving an apurinic\apyrimidinic (AP) site. In addition, several DNA glycosylases are bifunctional, since they also display a lyase activity that cleaves the phosphodiester backbone 3h to the AP site generated by the glycosylase activity. Structural data and sequence comparisons have identified common features among many of the DNA glycosylases. Their active sites have a structure that can only bind extrahelical target bases, as observed in the crystal structure of human uracil-DNA glycosylase in a complex with double-stranded DNA. Nucleotide flipping is apparently actively facilitated by the enzyme. With bacteriophage T4 endonuclease V, a pyrimidine-

show abstract

“…cDNA encoding part of the mouse MutY homolog has been cloned (GenBank accession nos AI0409068 and AA409965), although expression and characterization of the gene product remains unpublished (26). The gene for a human MutY protein (hMYH) has been cloned (27) and the predicted size of this hMYH is 59 kDa similar to the size of a band detected in HeLa nuclear extracts with an anti-MutY antibody (25). Recently the hMYH protein from the cloned cDNA has been expressed in an in vitro transcription/translation system (28) and in E.coli (26,29) and partially characterized.…”

Section: Introductionmentioning

confidence: 99%

“…The gene for a human MutY protein (hMYH) has been cloned (27) and the predicted size of this hMYH is 59 kDa similar to the size of a band detected in HeLa nuclear extracts with an anti-MutY antibody (25). Recently the hMYH protein from the cloned cDNA has been expressed in an in vitro transcription/translation system (28) and in E.coli (26,29) and partially characterized. This expressed recombinant hMYH has adenine glycosylase activity on the A/8-oxoG mismatch but very weak activity on the A/G mismatch.…”

Section: Introductionmentioning

confidence: 99%

“…The mammalian MYH has adenine glycosylase and binding activities on A/8-oxoG and A/G mismatches and has recently been shown to possess glycosylase activity on 2-hydroxyadenine paired with A, G, T, C and 8-oxoG (24). cDNA encoding part of the mouse MutY homolog has been cloned (GenBank accession nos AI0409068 and AA409965), although expression and characterization of the gene product remains unpublished (26). The gene for a human MutY protein (hMYH) has been cloned (27) and the predicted size of this hMYH is 59 kDa similar to the size of a band detected in HeLa nuclear extracts with an anti-MutY antibody (25).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Purification and characterization of a mammalian homolog of Escherichia coli MutY mismatch repair protein from calf liver mitochondria

Parker

2000

Nucleic Acids Research

View full text Add to dashboard Cite

A protein homologous to the Escherichia coli MutY glycosylase, referred to as mtMYH, has been purified from calf liver mitochondria. SDS-polyacrylamide gel electrophoresis, western blot analysis as well as gel filtration chromatography predicted the molecular mass of the purified calf mtMYH to be 35-40 kDa. Gel mobility shift analysis showed that the purified mtMYH formed specific binding complexes with A/8-oxoG, G/8-oxoG and T/8-oxoG, weakly with C/8-oxoG, but not with A/G and A/C mismatches. The purified mtMYH exhibited DNA glycosylase activity removing adenine mispaired with G, C or 8-oxoG and weakly removing guanine mispaired with 8-oxoG. The mtMYH glycosylase activity was insensitive to high concentrations of NaCl and EDTA. The purified mtMYH cross-reacted with antibodies against both intact MutY and a peptide of human MutY homolog (hMYH). DNA glycosylase activity of mtMYH was inhibited by anti-MutY antibodies but not by antihMYH peptide antibodies. Together with the previously described mitochondrial MutT homolog (MTH1) and 8-oxoG glycosylase (OGG1, a functional MutM homolog), mtMYH can protect mitochondrial DNA from the mutagenic effects of 8-oxoG.

show abstract

Cloning and sequencing a human homolog (hMYH) of the Escherichia coli mutY gene whose function is required for the repair of oxidative DNA damage

Cited by 357 publications

References 20 publications

Cloning and characterization of hOGG1 , a human homolog of the OGG1 gene of Saccharomyces cerevisiae

Cloning and characterization of hOGG1 , a human homolog of the OGG1 gene of Saccharomyces cerevisiae

DNA glycosylases in the base excision repair of DNA

Purification and characterization of a mammalian homolog of Escherichia coli MutY mismatch repair protein from calf liver mitochondria

Contact Info

Product

Resources

About