Genome-wide, drug-induced changes in H4 acetylation.

<p><b>A</b>) Annotated gene map of a 30 kb representative region of the Drosophila chromosome 3R. The coding region of depicted genes is shown as connected boxes. Genes in the top row are transcribed from the plus (+) strand (left to right); genes in the bottom row are transcribed from the minus (−) strand (right to left). <b>B</b>) Histone acetylation profile of chromatin isolated from wild-type fly heads. Plot shows histone H4 acetylation levels of untreated control flies across the same chromosomal region displayed in (<b>A</b>). Bars represent the normalized IP/input ratios of fluorescently labeled chromatin signals detected by a single DNA tilling array. <b>C–D</b>) Difference plot showing the changes in histone H4 acetylation between control flies and benzyl alcohol-treated flies (<b>C</b>) or control flies and ethanol-treated flies (<b>D</b>) across the same chromosomal region displayed in (<b>A</b>). Bars are log2 values of the normalized IP-treated/IP-control ratios of fluorescently labeled chromatin signals detected by a single DNA tilling array. The red rectangle highlights a representative example of a statistically significant drug-induced acetylation spike shared by both drug treatments. The depicted red gene identifies the closest gene loci associated with the drug-induced acetylation spike. <b>E</b>) Diagrammatic representation of the overlap between the cohorts of genes with significant changes in acetylation induced by benzyl alcohol, ethanol or both.