Trans-complementation of NS1 is disabled by using cDNA clones possessing deletion in the NS1 genes of JEV or DENV.
(A) An illustration shows the experimental workflow. A schematic representation of the deletion mutants of flaviviruses. The region of the deletion was 12–894 nt (4–298 aa) of NS1. In vitro-transcribed RNAs of the NS1 deletion mutants were transfected into Vero E6 cells expressing NS1, and infectious titers in the culture supernatants were determined upon transfection into Vero E6 cells. Expression of JEV (B) or DENV (C) NS1 was determined by immunoblotting at 48 hpi of lentiviruses into Vero E6 cells. Infectious titers in the culture supernatants were determined upon either transfection of the in vitro-transcribed RNA of the NS1 deletion mutants or infection of wild type viruses at 4 days post-transfection or infection.