FIG. 2.

Relative positions of var intron sequences from region 2 and their effect on luciferase activities from pVLH constructs. (A) Locations of segments from region 2 and map of the constructed int149/R123 segment containing three imperfect repeats. (B) Levels of luciferase expression from constructs containing different segments of region 2. Control plasmids pVLH and pVLH+intΔ1Δ3 demonstrated complete activity and full silencing of luciferase, respectively. All experiments were repeated at least twice in triplicate, and all Student's t tests yielded P values of <0.05 for comparisons of luciferase levels from pVLH+intΔ1Δ3 and the individual plasmids. Bars on the histogram indicate 95% confidence intervals.