Figure 5. The direction of translational regulation is determined by the 3′-UTRs.

Using the reporter gene system different combinations of 5′- and 3′-UTRs of the hlr and the hp transcript were studied. (A) The transcript fusions are shown schematically. The DHFR enzymatic activities, the dhfr transcript levels and the translational efficiencies of exponential and stationary growth phases are tabulated. Three biological replicates were performed and average values with standard deviations (in parenthesis) were calculated. (B) The translational efficiencies after normalization to the control transcript without UTRs (No. 1) are shown.