Figure 6.

Identification of the enhancer and the repressive element within the intergenic region of the PDCD10-SERPINI1 gene pair. Various intergenic fragments were cloned upstream of either the SV40 or CMV promoter and of a luciferase reporter gene in the pGL3 vector. All constructs were transiently transfected into human neuroglioma H4 cells and the luciferase activity was measured. The resulting promoter activity was calculated relative to the control SV40 or CMV promoter activity which is artificially set at 100. A) The potential regulatory sequences from nt 176 to 851 of the intergenic region were cloned upstream of the SV40 promoter and their effects on the activity of the SV40 promoter were examined. B) Three intergenic fragments (nt 851-711, nt 710-474 and nt 473-176) in the PDCD10 direction were individually cloned upstream of the SV40 promoter to assess their effects on the activity of the SV40 promoter. C) Three different intergenic fragments (nt 711-851, nt 474-710 and nt 176-473) in the SERPINI1 direction were individually cloned upstream of the CMV promoter in a modified pGL3-Promoter vector. Their effects on the activity of the CMV promoter were then investigated. The numbering system for nucleotide position is the same as those described in Fig. 5. The length and the position of each promoter insert are shown in scale. In the names of constructs, S denotes the SV40 promoter and C denotes the CMV promoter.