Figure 3.

Higher sensitivity reporter assays do not demonstrate miRNA-like roles for other AGO-bound small RNAs. MDA-MB-231 cells were transfected with 5 × 5-fold serial dilutions of luciferase reporter plasmids containing sites fully complementary to a number of small RNAs assayed in Figure 2. Luciferase activity was determined in triplicate, 48 h post-transfection. Error bars depict standard error of mean. Greater suppression of luciferase reporters with reduced levels of transfected plasmid (for miR-15b-5p and SNORD56) indicates an increased capacity for this assay to detect miRNA-like function, though reporters for most other (non-miRNA/snoRNA-derived) RNAs are still not repressed, re-affirming their inability to perform gene suppressive roles.