FIGURE 3.

H3K4 methylation at frq under circadian conditions. ChIP analysis of H3K4me3 occurring at the frq locus. Cross-linked, sonicated lysates enriched for nuclei were isolated from WT (FGSC 2489) under circadian-entrained conditions and immunoprecipitated with an antibody that recognizes H3K4me3. The amount of DNA associated with the modification was determined by quantitative PCR and examined at the C-box (A) and within the FCR (B). A strain lacking SET1 (XB140-10) and a nonspecific IgG were used as negative controls. Values are the average of four independent ChIP experiments, and the error bars indicate the mean ± S.D. (p < 0.05 comparing peak, CT 13–16, and trough, CT 5). DD, constant dark; CT, circadian time.