Two ug of various promoter reporter constructs and 1 ng of Renilla luciferase reporter construct, as internal control, were cotransfected into HEK293 cells using PolyFect reagent. Firefly luciferase activity was normalized to Renilla luciferase activity. Results are expressed as the means of relative luciferase activity (relative to the activity of pGL-2 basic plasmid, arbitrarily set as 1) from five separate experiments, each performed in triplicate. The S.D. is indicated by the error bar. *, p<0.01 for construct −668 to −33 versus construct −454 to −33.