TLR4 −2242 T→C variant increases transcriptional activity of its promoter

ObjectiveTo investigate the effects of −2242, −1892 and −1837 single nucleotide polymorphisms (SNPs) on toll-like receptor 4 (TLR4) promoter activity.MethodsPolymerase chain reaction (PCR) and site direct mutation technology were used to construct TLR4 basic promoter and −2242C, −1892A and −1837G mutate promoter plasmids. Dual-Luciferase Reporter assay system was used to detect the activity of constructed promoter following human embryonic kidney (HEK) 293 cells were transiently cotransfected with the constructed plasmids and the control plasmid pRL-CMV.ResultsIn HEK293 cells, the activity of −2242C mutate promoter was higher than −2242T promoter, and there was no significant difference when both −1892A and −1837G mutate promoter compared with −1892G and −1837A promoter, respectively.ConclusionIt is implied that −2242T→C base variation can enhance the activity of TLR4 promoter, while −1892 and −1837 SNPs have no effect on TLR4 promoter activity.