Arabidopsis thaliana Raw sequence reads

We tested the hypothesis that miRNA loading is regulated during de-etiolation. To do this a quantitative and qualitative comparative study was performed between RISC bound (active) and total miRNA samples. Confirming previous studies, we found that miRNAome of input samples is only moderately altered, although expression level of several miRNA was significantly changed, these changes are slight except for miRNA163. We also found that loading efficiency was identical in dark and de-etiolated samples for all miRNAs except for miRNA163, which was five times more efficiently loaded in de-etiolated than in the dark sample.Taken together, although regulated RISC loading could play an important role in the organ-specific gene regulation, we found that RISC loading is non-regulated during de-etiolation except for the specific miRNA163. These finding and previous results support the surprising observation that although miRNAs play essential regulatory role in many phases of plant development, miRNAs are barely involved in the control of dramatic genetic reprogramming that occurs during de-etiolation.