On the epigenetic role of guanosine oxidation

Publication date: Available online 6 December 2019Source: Redox BiologyAuthor(s): Marco Giorgio, Ivan Gaetano Dellino, Valentina Gambino, Niccolo’ Roda, PierGiuseppe PelicciAbstractChemical modifications of DNA and RNA regulate genome functions or trigger mutagenesis resulting in aging or cancer. Oxidations of macromolecules, including DNA, are common reactions in biological systems and often part of regulatory circuits rather than accidental events.DNA alterations are particularly relevant since the unique role of nuclear and mitochondrial genome is coding enduring and inheritable information. Therefore, an alteration in DNA may represent a relevant problem given its transmission to daughter cells. At the same time, the regulation of gene expression allows cells to continuously adapt to the environmental changes that occur throughout the life of the organism to ultimately maintain cellular homeostasis.Here we review the multiple ways that lead to DNA oxidation and the regulation of mechanisms activated by cells to repair this damage. Moreover, we present the recent evidence suggesting that DNA damage caused by physiological metabolism acts as epigenetic signal for regulation of gene expression. In particular, the predisposition of guanine to oxidation might reflect an adaptation to improve the genome plasticity to redox changes.
Source: Redox Biology - Category: Biology Source Type: research

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AbstractThe hallmark of Lynch syndrome (LS)-associated neoplasia is DNA mismatch repair protein (MMR) deficiency. Recent studies have demonstrated that histologically normal colonic crypts in patients with LS can exhibit deficient MMR expression. The aim of this study was to determine the feasibility of detecting MMR deficient crypts in random colonoscopic biopsies of normal mucosa in patients with and without LS. Forty-nine patients, including 33 with LS, 12 without LS, and 4 with germline MMR gene variants of uncertain significance (VUS), were prospectively and blindly evaluated by immunohistochemistry for MMR deficient ...
Source: Familial Cancer - Category: Cancer & Oncology Source Type: research
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Source: Trends in Genetics - Category: Genetics & Stem Cells Source Type: research
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Source: Pharmacology and Therapeutics - Category: Drugs & Pharmacology Source Type: research
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Source: Journal of B.U.ON. - Category: Cancer & Oncology Tags: J BUON Source Type: research
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Source: Cancer Medicine - Category: Cancer & Oncology Authors: Tags: ORIGINAL RESEARCH Source Type: research
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Source: Cancers - Category: Cancer & Oncology Authors: Tags: Article Source Type: research
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Source: The Journal of Molecular Diagnostics - Category: Pathology Source Type: research
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Source: PLoS Computational Biology - Category: Biology Authors: Source Type: research
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Source: International Urogynecology Journal - Category: OBGYN Source Type: research
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Source: The Annals of Thoracic Surgery - Category: Cardiovascular & Thoracic Surgery Source Type: research
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