Figure 6: A model for coordinated transcriptional regulation of the EhPgp1 gene. This model represents our understanding of the EhPgp1 gene expression in the drug resistant clone C2 from E. histolytica. Our data demonstrate that the DNA sequences contained within the -226 to +24 bp of the EhPgp1 gene promoter are sufficient to direct EhPgp1 gene expression. We speculate that the C/EBP sequences are recognized by a C/EBP-like transcription factor and the R9(2) and may be the R9(1) have been recognized by an EhEBP1 protein. We do not know yet the order in which the proteins specifically recognize each sequence, neither how these proteins interact with the basal machinery, but we go on with the study of the EhPgp1 gene control. TPC, transcriptional preinitiation complex. Arrow, transcription initiation site.