Fig. 1: Identification of loss of function and dominant negative mutations in the ligand-binding domain of LXRα carried by participants in population biobanks.
We characterized 65 coding variants in the ligand-binding domain of LXRα in two separate assays. a, Stacked bar chart illustrating LXRα mutant activity. HEK293 cells were transfected with an LXR luciferase reporter construct and WT or mutant LXRα. At 4 h after transfection, cells were treated with indicated concentration of the LXRα agonist T0901317 and luminescence was measured as an index of LXRα activity 20 h later. The dashed coloured lines indicate average activity of WT LXRα at the corresponding concentration of T0901317. Statistical analysis of mutant versus WT activity was assessed by two-way ANOVA with Geisser–Greenhouse correction and multiple comparison controlling for false discovery rate (FDR) at each ligand concentration by two-stage step-up method of Benjamini, Krieger and Yekutieli. FDR-corrected P values are presented in Supplementary Table 1. Each mutant was tested in a minimum of three independent experiments, resulting in a total of 25 independent experiments conducted across seven individual batches. The height of bars and error bars represent mean ± s.d. b, Forest plot of mutant LXRα activity in a co-expression assay. WT and mutant LXRα and an LXR luciferase reporter construct were transfected into HEK293 cells. At 24 h later luminescence was measured as an index of LXRα activity. Assuming normal distribution, significant increases and decreases according to a two-tailed one-sample t-test are depicted in green and red, respectively. n = 4–8 independent experiments per variant were performed on different days in the same cell line. Dots and error bars represent mean ± 95% CIs. EV, empty vector; DM, an artificial double mutant that is strongly DN.
