Research Paper Volume 3, Issue 3 pp 223—236

Gain of survival signaling by down-regulation of three key miRNAs in brain of calorie-restricted mice


Figure 6. Effect of miRNAs on Bcl-2 3'UTR and rate of apoptosis in cell lines, using transfection assays. (A) miR-34a/−30e/181a-1* and Bcl-2 (3'UTR) co-transfected 293 cells express reduced red fluorescence, which shows that the 3’ UTR of Bcl-2 is repressed by the input miRNAs, but not by scrambled control and Bcl-2 (3'UTR) co-transfected cells. This shows that these miRNAs indeed suppress the target protein (red fluorescence protein) through the 3'-UTR of Bcl-2. This effect is absent when a plasmid carrying a scrambled sequence is used (indicated with arrows). (B) In line with the increase of apoptosome-specific proteins in the over-expression assay for these three miRNAs, over-expression in HEK-293 and NIH/3T3 cells contributes to a decline of the LD50 dose of Staurosporine, thus more cell death at lesser concentration; this effect on the LD50 dose is not present in scrambled and vector alone controls. (**p<0.01, **p<0.0001; all histograms represent average ±