Figure 3. Ajuba increases LXRα-induced target promoter activities.

A, Coexpression of Ajuba and LXRα-induced SREBP-1C-Luc activity. Human SREBP-1C gene promoter containing 2 functional LXREs (−311/−296 and −260/−245) was inserted into the pGL3 basic luciferase vector to make a SREBP-1C-Luc reporter. Reported assays were performed in 293T cells, and all reporter assays were repeated 3 times in triplicate. Data shown is an average of 3 independent experiments. B, Mouse SCD-1 gene promoter containing a functional LXRE (−1116/−1101) was cloned into pGL3.0 basic luciferase vector to make a SCD-1-Luc reporter and the LXRE was subsequently mutated. The luciferase assays were performed as the same as in A. C–E, Both LXRα and Ajuba bind the LXRE loci of LXRα target genes. ChIP assays in HepG2-vector and HepG2-shLXRα cells were performed using antibodies specific to LXRα and Ajuba. The coeluted DNA fragments were amplified by qPCR using primers flanking the functional LXREs at the promoters of SREBP-1C and SCD-1, the known target genes of LXRα, respectively. F and G, HepG2 cells were treated with DMSO or T090 for 24 hours, and the resulting cells were prepared for ChIP assays. Data shown were an average from 3 independent experiments. *, P < .05.