Figure 5.
Disruption of miRNA function results in up-regulation of disallowed genes. A, βDicer-null (KO, 7 to 8 weeks old) or control Dicerflox/flox (C) mice were injected with 2 mg of tamoxifen for 5 consecutive days. Two weeks after the last injection, total RNA was extracted from isolated islets and RT-qPCR used to evaluate the expression of the indicated genes (n = 9–13 mice/genotype). B, Sequences coding Oat, Fcgrt, Pdgfra, and Igfbp4 3′-UTRs were cloned downstream of the firefly luciferase open reading frame in the plasmid pmirGLO, as indicated. The constructs were transfected into islets extracted 2 weeks after tamoxifen injection of βDicer-null (KO) or control Dicerflox/flox (C) mice, as described under Materials and Methods. Data correspond to 2 technical replicates in islets from 3 to 5 different mice/genotype. *, P < .05; **, P < .01, Student t test.