Demethylation of O6-Methylguanine in DNA by O6-Methylguanine-DNA Methyltransferase: Synthesis and Characterization of O6,9-Dimethylguanine Coordinated with cis-Platin at the N7-Position.
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چکیده
منابع مشابه
Inhibition of human O6-methylguanine-DNA methyltransferase by 5-methylcytosine.
The ability of cloned human O6-methylguanine-DNA methyltransferase to repair a methylated guanine in a CpG-containing sequence, i.e., island, was studied by using a synthetic double-stranded 20-mer oligonucleotide from codon 248 of the p53 gene and another designed sequence. The double-stranded oligonucleotides incorporating 5-methylcytosine (5mC) and O6-methylguanine (O6mG) in various combinat...
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Methylation of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter (i.e., gene silencing) occurs in 40% to 50% of patients with glioblastoma and predicts benefit from temozolomide chemotherapy; when unmethylated, MGMT repairs DNA damage induced by temozolomide, contributing to chemoresistance. In this study, we tested the hypothesis that MGMT is regulated by p53 in astrocytic cells,...
متن کاملRibozyme-mediated modulation of human O6-methylguanine-DNA methyltransferase expression.
A synthetic oligonucleotide containing ribozyme sequences targeted to the 5' region of the human O6-methylguanine-DNA methyltransferase (MGMT) mRNA has been constructed. This ribozyme demonstrates cleavage activity in vitro in the presence of Mg2+. To determine whether this ribozyme can function in vivo, HeLa CCL2 cells were transfected with a mammalian expression vector containing the ribozyme...
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A plasmid encoding a recombinant human O6-methylguanine-DNA methyltransferase (MGMT) fused to a fragment of the bacteriophage lambda N protein has been constructed. The fusion protein retained methyltransferase activity when expressed at high levels in E.coli and was purified to essential homogeneity by a simple procedure. Antisera raised against the purified fusion protein recognized MGMT in w...
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We previously generated transgenic C3H/HeN mice by introducing the Escherichia coli O6-methylguanine-DNA methyltransferase (MGMT, DNA-O6-methylguanine:protein-L-cysteine S-methyltransferase, EC2.1.1.63) gene, ada, attached to the Chinese hamster metallothionein I gene promoter. One transgenic mouse line expressing both ada-specific mRNA and Ada protein could be propagated over many generations ...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1994
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.42.903