ChIP-PCR and ChIP-seq experiments were performed as previously described (17 (link)). Antibodies for histone modifications (anti-H3K4me, anti-H3K27ac, anti-H3K27me3 and anti-H3K36me3) were obtained from Millipore (Billerica, MA, USA). An anti-Flag M2 antibody (Sigma-Aldrich Corporation, St. Louis, MO, USA) was used in the ChIP experiments involving Flag-BmHP1a.