abstract
- During the construction of a physical map for Leishmania major (LV39) chromosome 2 we have rescued and characterized a L. major (LV39) derived genomic clone bearing solely as insert a long stretch of the miniexon gene array. The recombinant was devised as a tool to study the effect of miniexon overexpression on virulence and growth advantage. Such clone, 32D05, contains approximately 40 kb of the miniexon tandem array. We have examined the course of infection in susceptible BALB/c mice inoculated with transfectants carrying 32D05 as an episome. The study was carried out in two different clonal lines of L. major: virulent line LV39 (clone 5) and avirulent LT252 (CC1 clone). The results presented here indicate that high levels of miniexon expression affect negatively the ability of once virulent lines to induce lesions when injected in susceptible mice.