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 5

 Repair pathway selection in subtelomeric chromatin is modulated by histone modifications that define accessibility. During azole stress, increased acetylation of histone H3 at lysines 9 and 14, driven by the histone acetyltransferase Gcn5p, counteracts Sir2p-mediated deacetylation, opening chromatin around ERG11 (Todd & Selmecki, 2020). This shift enhances both transcriptional activation and mutational potential by facilitating polymerase passage and repair enzyme binding. The local nuclear chemistry — including NAD+/NADH ratios that modulate Sir2p activity — thereby regulates the equilibrium between silencing and mutability. What emerges is a redox-sensitive control loop where the chemical metabolism of the nucleus dictates its genetic dynamism.

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