Figure 3

Genotypic variations in miRNA expression. (a) The miR172 is the most abundantly expressed miRNA in sorghum stems. (b) The rest of the known miRNAs were expressed at very low abundance (less that 0.5% of the total reads in the library) in stem tissue. (c) The miRNA abundances were used to calculate their relative fold change in expression between BTx623 and Rio, and between the LB/EF F2s and HB/LF F2s libraries, respectively. Positive values in the y-axis of the graph denote fold changes in miRNA expression that are higher in BTx623 relative to Rio and higher in LB/EF F2s relative to HB/LF F2s libraries, respectively; the opposite is true for negative values. The expression of miR169 and miR172 was at least twice as high in BTx623 relative to that in Rio and this difference was inherited in the F2. The opposite was true for miR395 expression. (d-f) Quantification of miRNA expression through Taqman Assay in pools of 10 F2 plants each with similar flowering time (10-11 leaves) but different sugar content (Brix 3-5 vs Brix 13-16), respectively. (d) High expression of miR169d in BTx623 relative to Rio correlates with low Brix in the F2 independently of flowering time. (e-f) F2 plants with similar flowering time display no differences in miR395f and miR172a expression regardless Brix degree.