Figure 5.

Effects of Curcumin Pretreatment on the Acetylation State of H3 and H4 Histones Associated with the nfc102 Gene and Its Transcription in Confite and B73 Plants.

Leaf nuclei were prepared from UV-B–exposed (UV-B) and control (no UV-B) plants that were previously treated with curcumin as described in Methods. ChIP assays were done using antibodies specific for acetylated histone H3 ([A]; AcH3), acetylated H4 ([B]; AcH4), or total histone H4 ([C]; H4). The immunoprecipitates were analyzed for the presence of promoter and transcribed sequences of nfc102 and a transcribed sequence of a control gene that is not UV-B–regulated (th-like) by quantitative PCR. ChIP data were normalized to input DNA before immunoprecipitation. No signal was detected in control reactions (performed for each sample reaction reported above) incubated in the absence of any antibody. Quantitative RT-PCR analysis was also done to study transcript levels (nfc102 mRNA) in control and UV-B–treated plants (D). Fifty nanograms of cDNA after reverse transcription of RNA was used. All measurements were done at least in triplicate for each of the independent preparations. Error bars indicate se. None of the comparisons between the UV-B and control treatments showed statistically significant differences (Student's t test; P = 0.05).