Figure 6. Downstream elements preferentially regulate transcription initiating in the upstream promoter region.

HeLa cells were transfected with the wild type dropout construct (5 ug), which has a deletion in the region between −50 and +3 in the context of −416/+32 construct ligated to the luciferase (luc) reporter (see schematic at bottom on Figure), and derivative downstream elements mutant constructs with mutations at GLE and DPE-L1/2 (top). HeLa cells were also co-transfected with a CIITA-expression vector (or a control vector) and the dropout construct or its derivative downstream element mutants (bottom). The amount of luciferase activities was determined as described in Materials and Methods.