Development of a Sindbis virus expression system that efficiently expresses green fluorescent protein in midguts of Aedes aegypti following per os infection

A double subgenomic Sindbis (dsSIN) virus, MRE/3'2 J/GFP, was constructed t o efficiently express green fluorescent protein (GFP) in the midgut of Aede s aegypti following per os infection. The MRE/3'2 J/GFP RNA genome containe d the nonstructural genes and cis-acting sequences of the dsSIN virus, TE/3 '2 J/GFP, but had the structural genes of MRE16 SIN virus. MRE/3'2 J/GFP vi rus, unlike TE/3'2 J/GFP virus, efficiently infected mosquitoes orally. At 1-2 days postinfection, GFP was observed as multiple foci of expression on the lumenal side of the midgut. At 10-12 days postinfection, thirteen of fi fteen mosquitoes infected with MRE/3'2 J/GFP virus had high levels of GFP e xpression in the mosquito midgut. The MRE3'2 J dsSIN expression system shou ld be an important tool for efficient gene expression in Ae. aegypti midgut s.