Schematic representation of the composition and speculative nucleosome structure of a model B. bovis promoter. Angled arrows, thick lines, big circles, and boxes represent TSSs, DNA, histones, and coding sequences, respectively. Motifs in promoter regions are represented by small circles and the corresponding sequences are indicated by dashed arrows. The TYAYWWW motif over TSS is shown in Figures 1 and 2, and Table 2. The median length from TSS to the 5' end of CDS (5' UTR) was 152 bp (Additional file 2: Table S2). The ATGGGG motif and its reciprocal CCCCAT are distributed around -50 nt from TSS (Figure 3A and B). The ACACA, TGTGT, and TATAT motifs appear every 150 bp (Figure 3C). Positional relationships among the motifs and histones are arbitrarily described in this illustration.