Fig. 10.

MicroRNA (miR)-92 represses small cytoplasmic leucine rich repeat protein (SCLP) expression but not transcript abundance. A: the normalized relative luciferase activity (Renilla/Firefly) of the SCLP constructs when treated with miR-92b. The relative luciferase activity was compared 24 h after cotransfection of COS-1 cells with the construct [SCLP-3′-untranslated region (UTR) or SCLP-siRNA] and 1 µl of 20 nM miR-92b mimic. The 100% complementarity between miR-92b against the SCLP-3′-UTR repressed luciferase expression and served as a positive control for silencing. The use of miR-92b that targets the SCLP 3′-UTR also repressed expression. B: miR-92b was cotransfected with either SCLP-siRNA, a vector with a 3′-UTR target site completely complementary to miR-92b, or SCLP-3′-UTR, a vector with a 3′-UTR target site amplified from the 3′-UTR of SCLP. After 24 h, the cells were lysed, and Renilla luciferase expression was measured via quantitative (q)PCR and compared by the ∆∆Ct- method. Blue = control and red = treated. The use of an siRNA that was 100% complementary to the 3′-UTR led to transcript degradation, while the use of miR-92b against the authentic SCLP 3′-UTR did not alter transcript abundance, suggesting a block in translation. The Student’s t test was used to test statistical significance for the pairwise comparisons.