>ath-miR390a trigger TAS3 to produce ta-siRNAs clusters 
AAGCUCAGGAGGGAUAGCGCC
>ath-miR173 trigger TAS1a,b,c and TAS2 to produce ta-siRNAs clusters
UUCGCUUGCAGAGAGAAAUCAC
>ta-siR2140 make PPR to degrade and generate ta-siRNAs clusters
AUAUCCCAUUUCUACCAUCUG