Global mRNA decay analysis at single nucleotide resolution reveals segmental and positional degradation patterns in a Gram-positive bacterium

Table 2 Determination of directionality of mRNA decay for B. cereus strains ATCC 10987 and ATCC 14579, based on rank statistics (Spearman rho)

^aThe log2 ratio of the coverage at each time-point to the coverage at t0 was calculated, and the rank correlation (Spearman rho) between this ratio (for each time-point separately) and the nucleotide number throughout each ORF (that is, distance to the 5' end) was determined. A positive rho signifies that coverage is dropping faster near the 5' end of the molecule, that is, the mRNA is predominantly degraded from the 5' end. For each ORF a rho higher than 0.3 or lower than -0.3, and a P-value < 0.0005 at t10, was interpreted as 5' to 3' direction of decay or 3' to 5' direction of decay, respectively. ^bThe average rho of the ORFs for which a direction of decay could be determined is given, showing that the directionality increases over time.

ISSN: 1474-760X