Figure 6From: The transcriptome landscape of Prochlorococcus MED4 and the factors for stabilizing the core genome Operon distribution of different expression subclasses. (a) Comparison of nonsynonymous substitution rate between operon genes and non-operon genes in MED4 (Mann–Whitney U Test, two-tailed). A circle represents an outlier. (b) Operon rate of four expression subclasses (HEG, MEG, LEG, and VEG) or the core/flexible genomes (Fisher’s exact test, one-tailed). The operon rate was defined as the ratio of operon genes to total genes in a certain gene collection. The operon rate of each subclass was normalized by the whole genome operon rate (55.5%). P-value ≤ 0.05 was indicated in figure. Core, the core genome; Flexible, the flexible genome; HEG, highly expressed genes; MEG, moderately expressed genes; LEG, lowly expressed genes; VEG, variably expressed genes.Back to article page