Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Chromatin Landscape - Nuclear Biology & Nuclear Chemistry Aproaches - The Chemical Ecology of the Nuclear Space: Redox Dynamics, Heme Chemistry, and the Molecular Governance of ERG11 - Non-Elaborate Posts - Post 6

 

 Chromatin’s structural plasticity responds directly to nuclear redox fluctuations. Histone acetylation and methylation enzymes depend on cofactors sensitive to redox balance, such as NAD⁺ (for sirtuin activity) and FAD (for demethylase reactions). In oxidative conditions, NAD⁺ depletion suppresses sirtuin-mediated deacetylation, leading to chromatin loosening and enhanced transcription of redox-protective genes — including ERG11. Meanwhile, oxidation of histone cysteines alters nucleosome stability, subtly modulating chromatin fiber elasticity. In subtelomeric domains, these chemical transitions result in transient euchromatinization, providing ERG11 an ephemeral window of transcriptional activation. This dynamic chromatin–redox coupling illustrates how nuclear chemistry establishes feedback between cellular metabolism and genomic accessibility.

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