Fig. 7.

RNAi-mediated suppression of PPARγ reduces adipocyte GIPR expression. A: Effects of PPARγ siRNAs on PPARγ expression are shown. Differentiated 3T3-L1 adipocytes were transfected with a pool of three siRNAs for PPARγ or control scrambled siRNAs (100 nM) and incubated for 72 h. Nuclear extracts were isolated, and Western blot analyses were performed as described in “Experimental Procedures,” using antibodies against PPARγ2, PPARγ, and histone H3. B: Effects of PPARγ siRNAs on GIPR expression are shown. 3T3-L1 adipocytes were treated as described in the legend to panel A, and real-time RT-PCR was performed with extracts to quantify GIPR mRNA levels, shown as the fold difference versus control normalized to 18S rRNA expression levels. All data represent three independent experiments, each carried out in duplicate, and Western blots are representative of n = 3 replicates. Significance was tested using a Student t test, where ** represents P <0.05 versus control siRNA.