Fig. 3

Circular representation and correspondence analysis of expression of trans-encoded sRNAs in Synechocystis under control and five stress conditions. a From outside to inside: (1) Whole chromosome and four plasmids (pSYSM, pSYSA, pSYSG, and pSYSX) of Synechocystis with color order orange, yellow, green, blue, and purple, respectively. Numbers in blue labeled outside the circle reflect the scale, and each unit corresponds to 0.01 M of the genome; (2) Location of sRNAs in the Synechocystis genome. Several key sRNAs were labeled in the outer circle: biofuel-responsive sRNAs are in black; names of the top abundant sRNAs are marked in red; (3) Circular boxplot presentation for the range of sRNA absolute expression levels under various conditions (recorded as the log₁₀-transformed maximum, upper quartile, median, lower quartile, and minimum expression values of sRNA in 18 different samples). Higher sRNA expression is correlated with a further outside boxplot position; (4) Circular heatmap presentation for sRNA log₂-transformed expression changes under five stress conditions at 24, 48, and 72 h. From outside to inside, the order is E24, E48, E72, B24, B48, B72, H24, H48, H72, S24, S48, S72, N24, N48, and N72. The color scale is in the top-left corner of the figure. Several biofuel-responsive sRNAs or stress-specific responsive sRNAs are marked by black framed lines; b Correspondence analysis of sRNA expression under 18 experimental conditions. Samples in control, ethanol, butanol, hexane, salt, or nitrogen starvation conditions are labeled black, red, orange, yellow, green, and blue, respectively. Each gray number represents one of the 133 identified trans-encoded sRNAs. The x-axis and y-axis represent the first dimension and the second dimension, respectively, for correspondence analysis