Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Chromatin Landscape - Nuclear Biology & Nuclear Chemistry Aproaches - Non-Elaborate Posts - Post 3


Subtelomeric regions in fungi, much like in higher eukaryotes, are subjected to a gradient of heterochromatinization. In C. albicans, the histone deacetylase Sir2p, the telomeric DNA-binding factor Rap1p, and the structural protein Rif1p collaborate to propagate telomeric silencing toward adjacent genes (Anderson et al., 2015). This “telomere position effect” creates a repressive chromatin environment that can silence nearby genes through hypoacetylated nucleosome formation and compacted chromatin looping. For ERG11, such subtelomeric silencing establishes a basal repression state, buffering the cell against metabolic overproduction of sterol intermediates. The silencing, however, is not absolute — it is modulated by nuclear positioning, stress signaling, and local chromatin remodeling factors, ensuring functional responsiveness within structural constraint.

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