Histone H3 association with active gene promoters is increased in Mediator mutants.
A, histone H3 association with the CHA1 promoter was measured by ChIP using wild type (BY4742) and gal11/med15Δ med3Δ (LS10) yeast grown in CSM without (uninduced) or with (induced) 1 mg/ml of serine. B, histone H3 association with the indicated promoters was measured in wild type (RMY521) and srb4/med17 ts (RMY522) yeast grown in YPD after 1 h growth at 37 °C. C, histone H3 association with promoters whose transcription is dependent or independent of the Mediator tail module, as indicated, was measured in wild type (BY4742) and gal11/med15Δ med3Δ (LS10) yeast grown in YPD. Relative association in all cases was determined by quantitative PCR analysis of input and immunoprecipitated (IP) samples, and normalized to a non-transcribed region of ChrV (25). Error bars represent S.D. (n = 3).