Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Nuclear Biology & Nuclear Chemistry Aproaches - Chromatin Chemistry and Epigenetic Modulation - Non-Elabirate Pists - Post 3

 

 Histone acetylation plays a defining role in modulating ERG11 transcriptional competency. Acetyltransferases such as Gcn5p and Esa1p deposit acetyl groups onto lysine residues of H3 and H4 tails, neutralizing their positive charge and loosening DNA-histone interactions (Finkel et al., 2021). This chemical relaxation exposes promoter regions, enabling RNA polymerase II recruitment. Conversely, histone deacetylases (Hda1p, Rpd3p, and Sir2p) remove these acetyl groups, reinstating nucleosomal rigidity and reestablishing local repression. In the context of antifungal exposure—particularly to azoles—acetylation levels at ERG11 spike sharply, reflecting a direct chromatin response to metabolic demand. Thus, acetylation serves not merely as an epigenetic mark, but as a biochemical dial modulating gene accessibility in real time.

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