Fig. 1: Cy3 labeling of dsRNA does not affect Dcr-2’s cleavage activity.

a Schematic of the double-stranded RNA substrate labeled with 3× Cy3 at designated positions. Scissors represent cleavage sites. b dsRNA cleavage assay using wild-type Dcr-2 or the RNase III mutant (III) (~15 nM), BLT or 3′ovr dsRNAs (5 nM), and ±Loqs-PD (50 nM). n = 3 independent experiments. c dsRNA cleavage assay for the helicase (H) and RNase III mutants. Enzyme and dsRNA concentrations were the same as in b and the incubation time was 10 min. n = 2 independent experiments. d dsRNA cleavage assay with a higher concentration of Dcr-2, using wild-type Dcr-2 or the helicase mutant (~30 nM), and BLT or 3′ovr dsRNA (1 nM) with or without ATP. The incubation time was 120 min. n = 2 independent experiments. e dsRNA cleavage assay for the comparison between non-labeled and Cy3-labeled dsRNAs. In b–e one strand of dsRNAs was radiolabeled at the 5ʹ end and detected by phosphor imaging (see “Methods” section). n = 3 independent experiments. Source data are provided as a Source Data file.