Fig. 1

The clock regulates expression of histone methyltransferase (SDG2) and demethylase (JMJ14) genes. a, b Relative expression levels (R.E.L.) of SDG2 (a) and JMJ14 (b) in the wild type (WT, Ws), cca1 lhy mutant (Ws) (upper panel), and WT (Col-0) and CCA1-OX (Col-0) (lower panel) plants under a diurnal cycle (16 h light/8 h dark). Black and white bars indicate dark (ZT16, 20, and 24) and light (ZT28, 32, 36, and 40), respectively. c ChIP-qPCR showed the fold enrichment (Y-axis) of CCA1-binding fractions in the promoters of SDG2 and JMJ14 using rosette tissues from 3-week-old A. thaliana at ZT0. The TOC1 promoter containing evening elements was used as the positive control. UBQ10 was used as a nonbinding control for normalization. Error bars in a–c indicate standard deviation of biological replicates (n = 3) with an asterisk showing the statistical significance level (P < 0.05, Student t test). d Binding profiles of H3K4me3 at the TSS ± 1.5 kb in the wild type and cca1 lhy mutant with two biological replicates. e Examples showing decreased binding of H3K4me3 to the genes AT1G21270 (upper panel) and AT3G05880 (lower panel) in cca1 lhy mutant compared with the WT (Ws)