Figure 1.

Degradation pattern for the gap operon in B. cereus ATCC 10987 at single nucleotide resolution, determined by RNA-Seq. The upper panel indicates the position of annotated genes in the operon, with the heights of the bars representing the expression values for each gene at t0, and with estimated half-lives and gene names or locus tags given underneath. Transcriptional terminators, as predicted by TransTermHP, are marked by red vertical lines with filled circles. The middle panel shows the coverage per base pair for each nucleotide in the region at t0, while the lower panel shows the log2 ratio of the coverage per base pair for each of the time points following transcriptional arrest, relative to t0 (red, t = 2.5 minutes; green, t = 5 minutes; blue, t = 10 minutes). The B. cereus gap operon showed a similar degradation pattern to what has been observed in B. subtilis [53]. The solid black vertical line represents the site corresponding to the characterized RNase processing site in B. subtilis, where the part of the mRNA encoding the operon regulator CggR is cleaved off and degraded faster than the rest of the operon. Both the position of the RNase cleavage site and the pattern of faster decay of the cggR mRNA relative to the rest of the operon seem to be conserved in B. cereus. NA, not available.