Figure 2

Human LDLR PS2 enhancer exhibits significantly higher activity than orthologous lemur, mouse, and dog enhancers. Luciferase assay analysis of (a) transient transfections into human 293T cells and (b) plasmid DNA transfer into mouse liver. The luciferase reporter constructs tested are either the LDLR promoter alone (promoter) or the promoter in combination with the LDLR PS2 enhancer from one of the indicated species. Error bars indicate standard deviation. 'SRE mutant' refers to the mutagenized human sterol regulatory element (SRE) with four point substitutions relative to the wild-type (WT) SRE (Figure 4a). Luciferase activity is reported in arbitrary units. Each triangle in panel b represents luciferase activity in an individual mouse. Red bars denote the median activity of each construct.