Figure 2.
Alternative models for hc-siRNA/target interactions. Model 1: AGO4-bound hc-siRNAs identify target sites on nascent Pol V RNAs, but don’t cleave them. Model 2: AGO4-bound hc-siRNAs identify target sites in genomic DNA within the Pol V transcription bubble. Model 3: Like model 1, except that AGO4 catalyzes slicing of the Pol V RNA.