BRD4 is enriched at the promoters of active genes in round spermatids. (A) ChIP-seq of BRD4 and various histone PTMs reveals that BRD4 and histone H3 and H4 acetylation are associated with gene-rich regions of the genome while H3K9me3 is enriched in gene-poor intergenic regions. UCSC-defined genes are shown at the bottom. Genomic location is indicated at the top. The y axis is ChIP enrichment (normalized to the input). The x axis is DNA sequence. (B) Percentages of defined ChIP-seq peaks of BRD4, BRDT, and various histone PTMs in promoter (1 kb upstream of the TSS), gene (intron versus exon), and intergenic regions in round spermatids. (C) ChIP-seq of BRD4 and various histone PTMs at housekeeping (Actb) and spermatogenesis-specific (Tnp1) transcriptionally active genes and an inactive gene, Myc. BRD4 is not present at all gene promoters that are enriched for H3/H4 acetylation (Vps45). UCSC-defined genes are shown at the bottom in dark blue. The y axis is ChIP enrichment (normalized to the input). The x axis is DNA sequence.