Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Chromatin Landscape - Nuclear Biology & Nuclear Chemistry Aproaches - Redox–Chromatin Coupling - Non-Elaborate Posts - Post 4


ERG11’s protein product depends on a heme prosthetic group for its catalytic demethylation of lanosterol. However, heme is not merely a cytosolic cofactor — it is also a nuclear signaling molecule. Nuclear heme levels influence the activity of heme-responsive transcription factors (HRFs), such as Hap1p homologs, which bind to ERG11 promoter motifs. When oxidative stress sequesters or oxidizes heme, these HRFs dissociate, attenuating transcription. Conversely, heme abundance signals metabolic sufficiency and induces ERG11 transcription. This dynamic constitutes a feedback loop: the nuclear chemistry of heme iron governs the expression of its own metabolic machinery, creating a self-referential biochemical circuit of redox control.

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