Heterochromatin, though classically associated with gene silencing, serves as a reservoir of potential variation in Candida albicans. In subtelomeric regions, reversible transitions between heterochromatin and euchromatin states occur during stress responses, mediated by histone-modifying enzymes such as Sir2p, Hda1p, and Set1p (Dunkel & Morschhäuser, 2017). These transitions not only alter gene expression but also modulate DNA accessibility to replication and repair machinery. The cyclical modulation of ERG11’s chromatin status thus integrates environmental sensing with mutational readiness. Evolutionarily, this creates a tunable interface between genome protection and innovation, a hallmark of fungal survival under chemical duress.

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