Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Nuclear Biology & Nuclear Chemistry Aproaches - Chromatin Accessibility, Nuclear Chemistry, and Mutation Propensity of the ERG11 Locus in Candida albicans - Non-Elaborate Posts - Post 3

 At the molecular heart of chromatin regulation lies the histone code — a series of covalent modifications that alter nucleosomal charge and binding affinity. Acetylation of histone H3 and H4 tails by Gcn5p weakens DNA-histone interactions, rendering the ERG11 promoter more accessible to transcription factors and polymerases (Todd & Selmecki, 2020). Conversely, deacetylation by Hda1p restores compaction, repressing transcription. These enzymatic modifications depend intimately on intracellular metabolites: acetyl-CoA serves as the substrate for acetyltransferases, while NAD+ drives Sir2p-mediated deacetylation. Thus, the nuclear chemical economy — governed by cellular metabolism — becomes a direct determinant of the genetic expressivity and mutational fate of ERG11.

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