Physical and functional mapping of the transcriptional start sites of Plasmodium falciparum proliferating cell nuclear antigen.

RNase protection assays and primer extension analysis have been used to locate a major transcription start site 960 bp upstream from the translational start of the PfPCNA coding sequence. A second, minor, site is situated a further 40 bp upstream. Intraerythrocytic parasite stages were transiently transfected with constructs containing a firefly luciferase reporter gene under the transcriptional control of variously modified elements of the PfPCNA 5' flanking sequence. These experiments identified a 470 bp region essential for promoter activity, which contains the physically mapped transcriptional start sites. In addition, a region between 290 and 620 bp upstream of the transcriptional start sites is required for efficient promoter activity.