Fig. 8
From: Transcriptional silencing in Saccharomyces cerevisiae: known unknowns
Hysteresis in gene silencing. An active domain requires deacetylation of 75% of the nucleosomes to become silenced. A silent domain requires acetylation of 75% or more nucleosomes to lose silencing. Red circles denote unacetylated histones and green circles denote acetylated histones. Moon shapes denote Sir proteins; gray rectangles are silencers and black rectangles are enhancers and promoters