Analysis of chromatin remodeling at the RBCS2 promoter within the first 10 minutes after onset of heat stress. Chlamydomonas cells of strain 325-412 were subjected to heat stress and samples for ChIP were taken prior to and at the indicated time points after shifting from 24°C to 40°C. qPCR was used to quantify the amount of RBCS2 promoter fragments precipitated with antibodies against histone H3, di-acetylated histone H3, and tetra-acetylated histone H4. The enrichment relative to 10% input DNA was calculated. All values are normalized against those obtained for the CYC6 promoter (control). qPCR data from ChIPs with antibodies against modified histones are given relative to the nucleosome occupancy. Error bars indicate standard errors from two biological replicates, each analyzed in triplicate. Asterisks indicate the significance of change compared with non-stress conditions (Holm-Sidak t-test, p value ≤ 0.05).