Characterization of AGO1-/AGO4-associated smRNAs

To fully characterize smRNAs associated with AGO1 and AGO4, we developed a two-step protocol to purify AGO/smRNA complexes from flowers, leaves, roots and seedlings with enhanced purity, and sequenced the smRNAs by Illumina’s technology. We identified some additional miRNAs, collateral miRNAs encoded in known miRNA precursors, phased smRNA clusters and nat-siRNAs. Organ specific sequencing provided digital expression profiles of all obtained smRNAs, especially miRNAs. We used extracts from Arabidopsis flowers, leaves and roots as well as ten-day old seedlings to purify smRNAs associated with AGO1 and AGO4 protein complexes using a two-step immunoprecipitation method.