TRANSIENT EXPRESSION OF LUCIFERASE IN ENTAMOEBA-HISTOLYTICA DRIVEN BYTHE FERREDOXIN GENE 5'-REGION AND 3'-REGION

We have successfully transfected Entamoeba histolytica trophozoites wi th constructs containing ferredoxin sequences fused to the reporter ge ne luciferase. We have determined the conditions and parameters necess ary to maximise transient luciferase expression in our system. Our opt imal construct gave values of 268 x 10(3) relative light units per sec ond (RLU s(-1)) when assayed representing a stimulation of 18 000-fold over the control vector. Comparison of differing constructs allowed u s to conclude that the 5' and 3' ferredoxin sequences are both necessa ry for optimal luciferase expression from our vectors. Transcriptional initiation occurs within the consensus sequence ATTCA in both constru ct and chromosomal ferredoxin promoters.