Regulation of an amino acid transporter mRNA in Trypanosoma brucei

Trypanosoma brucei regulates gene expression by post-transcriptional mechanisms, such as mRNA turnover and translation control. This regulation frequently requires specific sequences located in the 3′-untranslated region. Microarray analysis and Northern blot hybridization showed that the amino acid transporter 11 mRNA is up-regulated in insect stages of the parasite. By RT-PCR and sequencing, the AATP11 polyadenylation site was mapped. We show that this 3′-UTR causes higher expression of the chloramphenicol acetyltransferase (CAT) reporter gene in procyclic trypanosomes than in bloodstream forms. Results of deletion analysis suggested that multiple elements located between nucleotides 141 and 618 of the 3′-untranslated region are required for this control.