Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Nuclear Biology & Nuclear Chemistry Aproaches - Structural Fragility and Replication Dynamics Near the ERG11 Subtelomeric Region in Candida albicans - Non-Elaborate Posts - Post 7

 The subtelomeric DNA near ERG11 is especially sensitive to oxidative lesions generated during antifungal exposure. Reactive oxygen species oxidize guanine bases, forming 8-oxoguanine adducts that mispair with adenine, leading to transversion mutations. The base excision repair (BER) pathway attempts to correct these lesions, yet its efficiency declines in heterochromatic contexts. Moreover, heme-dependent nuclear enzymes that buffer oxidative stress also influence repair enzyme activity through redox modulation (Puig & Gutiérrez, 2022). This coupling of chemical oxidation with enzymatic adaptation allows oxidative damage to serve as both a mutagenic and regulatory signal, positioning ERG11’s mutation rate at the intersection of nuclear chemistry and DNA repair.

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