Fungi - Candida albicans - Research News, Data, Publications & Aproaches - ERG11 Mutations - Telomeres - Sub-Telomeric Structures - Nuclear Biology & Nuclear Chemistry Aproaches - Chromatin Accessibility, Nuclear Chemistry, and Mutation Propensity of the ERG11 Locus in Candida albicans - Non-Elaborate Posts - Post 6

 The positional stability of nucleosomes modulates DNA exposure time to mutagens and polymerases. Remodelers such as RSC and SWI/SNF reposition nucleosomes at the ERG11 promoter in response to stress, generating nucleosome-depleted regions conducive to transcription initiation (Finkel et al., 2021). However, these regions also become hotspots for oxidative lesions, cytosine deamination, and replication slippage. The frequency of base transitions and insertions within these exposed intervals surpasses that of adjacent nucleosome-occupied DNA. Consequently, the nuclear choreography of nucleosomes determines not only the rhythm of transcription but the probability landscape of mutation — a subtle and beautiful interplay between structure and chemical risk.

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