ChIP-qPCR using H3K27me3 antibodies of BrFLC genes before and after four weeks of cold treatment. Upper panel is the gene structure of three BrFLC paralogs. Black boxes represent exon and arrows represent the primer position for ChIP-qPCR. Bottom panel shows the level of H3K27me3 in three BrFLCs before and after four weeks of cold treatment. Y-axis represents the ratio compared to BrSTM, which is an H3K27me3-marked gene. Data presented are the average and standard error (s.e.) from three biological and experimental replications. Statistical tests between NV and 4wkV or between NV and 4wkV + 7d are shown (Student t-test, *p < 0.05, **p < 0.01). NV, non-vernalized; 4wkV, four weeks of cold treatment; 4wkV + 7d, four weeks of cold treatment and then seven days normal growth condition.