FIG. 3.
Construction of viJ1R for conditional expression of J1R protein. (A) Schematic diagram of the parental virus vT7lacOI, the intermediate virus vJ1R/iJ1R, and the final mutant virus viJ1R. The J1R, J2R (thymidine kinase [TK]), and A56R (hemagglutinin) loci are indicated. DNA fragments inserted into these loci are shown below the lines. Abbreviations: T7 pol, bacteriophage T7 RNA polymerase gene; lacO, E. coli lac operator; PL, viral late promoter; PE/L, viral early and late promoters; lacI, E. coli lac repressor; EMC, encephalomyocarditis virus cap-independent translation enhancer element; gpt, E. coli guanine phophoribosyltransferase gene; P7.5 and P11, viral promoters; PT7, promoter for T7 RNA polymerase. (B) Expression of J1R protein in cells infected with viJ1R. Cells were infected with vT7lacOI or viJ1R at an MOI of 5 PFU per cell and harvested for Western blotting with antibody against J1R protein. M, mock-infected cells.