Fig. 2: XBP1s enhances insulin-mediated PPARγ activation in adipocytes.

3T3-L1 adipocytes were transfected with control vector (EV) or pcDNA3.1-mXBP1s (XBP1s) and treated for 30 min with insulin (1 μg ml−1). a XBP1s and PPARγ (1 and 2, or total) mRNA and protein levels were analyzed by real-time PCR and/or immunoblotting (left) and quantified with densitometry (right). b The effect of an XBP1s and PPARγ activator (rosiglitazone, Rosi) or inhibitor (GW9662) on DR1 promoter activity (left) and the expression of the PPARγ target genes aP2, CD36, and LPL (right) were examined by real-time PCR. c The effect of GW9662 on the XBP1s-mediated increase in glucose uptake was measured. d The effect of XBP1s on adiponectin mRNA and secreted protein levels were determined using real-time PCR and ELISA, respectively. Values are presented as the means ± SEM of three independent experiments. *P < 0.05 compared to EV. #P < 0.05 compared to XBP1s. n.s. not significant