Evidence has been accumulating at the oligomer level that free radical-initiated DNA damage includes lesions in which two adjacent bases are both modified. Prominent examples are lesions in which a pyrimidine base is degraded to a formamido remnant and an adjacent guanine base is oxidized. An assay has been devised to detect double-base lesions based on the fact that the phosphoester bond 3' to a nuclesoside bearing the formamido lesion is resistant to hydrolysis by nuclease P1. The residual modified dinucleoside monophosphates obtained from a nuclease P1 (plus acid phosphatase) digest of DNA can be (32)P-postlabeled using T4 polynucleotide kinase. Using this assay the formamido single lesion and the formamido-8-oxoguanine double lesion were detected in calf thymus DNA after X-irradiation in oxygenated aqueous solution. The lesions were measured in the forms d(P(F)pG) and d(P(F)pG(H)), where P(F) stands for a pyrimidine nucleoside having the base degraded to a formamido remnant and G(H) stands for 8-oxo-deoxyguanosine. The yields in calf thymus DNA irradiated 60 Gy were 8.6 and 3.2 pmol/microgram DNA, respectively.
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http://dx.doi.org/10.1006/abbi.1999.1640 | DOI Listing |
DNA Repair (Amst)
February 2023
Département de Biologie, Université de Sherbrooke, Sherbrooke, QC, Canada J1K 2R1; Institut de Recherche sur le Cancer de l'Université de Sherbrooke (IRCUS), Sherbrooke, QC, Canada J1E 4K8; Centre de recherche du Centre hospitalier universitaire de Sherbrooke (CRCHUS), Sherbrooke, QC, Canada J1H 5N3. Electronic address:
Illudin S (ILS) is a fungal sesquiterpene secondary metabolite with potent genotoxic and cytotoxic properties. Early genetic studies and more recent genome-wide CRISPR screens showed that Illudin-induced lesions are preferentially repaired by transcription-coupled nucleotide excision repair (TC-NER) with some contribution from post-replication repair pathways. In line with these results, Irofulven, a semi-synthetic ILS analog was recently shown to be particularly effective on cell lines and patient-derived xenografts with impaired NER (e.
View Article and Find Full Text PDFNucleic Acids Res
October 2022
Centre de Biophysique Moléculaire (CBM), UPR4301 CNRS, Université d'Orléans, CS 80054, rue Charles Sadron, F-45071 Orléans cedex 02, France.
8-Oxoguanine (GO) is a major purine oxidation product in DNA. Because of its highly mutagenic properties, GO absolutely must be eliminated from DNA. To do this, aerobic and anaerobic organisms from the three kingdoms of life have evolved repair mechanisms to prevent its deleterious effect on genetic integrity.
View Article and Find Full Text PDFBMC Genomics
February 2022
Princess Máxima Center for Pediatric Oncology, Heidelberglaan 25, 3584CS, Utrecht, The Netherlands.
Background: The collective of somatic mutations in a genome represents a record of mutational processes that have been operative in a cell. These processes can be investigated by extracting relevant mutational patterns from sequencing data.
Results: Here, we present the next version of MutationalPatterns, an R/Bioconductor package, which allows in-depth mutational analysis of catalogues of single and double base substitutions as well as small insertions and deletions.
Metallomics
January 2018
Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, CZ-61265 Brno, Czech Republic.
Polynuclear platinum complexes represent a unique structural class of DNA-binding agents of biological significance. They contain at least two platinum coordinating units bridged by a linker, which means that the formation of double-base lesions (cross-links) in DNA is possible. Here, we show that the lead compound, bifunctional [{trans-PtCl(NH)}μ-trans-Pt(NH){HN(CH)NH}] (Triplatin or BBR3464), forms in DNA specific double-base lesions which affect the biophysical and biochemical properties of DNA in a way fundamentally different compared to the analogous double-base lesions formed by two adducts of monofunctional chlorodiethylenetriamineplatinum(ii) chloride (dienPt).
View Article and Find Full Text PDFFree Radic Res
May 2016
Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Mie , Japan.
Chloramphenicol (CAP) was an old antimicrobial agent. However, the use of CAP is limited because of its harmful side effects, such as leukemia. The molecular mechanism through which CAP has been strongly correlated with leukemogenesis is still unclear.
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