Table 1.

Effect of varying the ratio of wt to mutant DNA on the infectivity of ampho-MuLV Env-pseudotyped virionsa

Molecular clonewt:mutant DNARelative infectivity
pNLuc
 Alone100
 +pNLuc/20LK/73EK/82AT10:133 ± 5
5:119 ± 4
2:14 ± 1
1:10.6 ± 0.1
1:20.2 ± 0.04
1:50.05 ± 0.01
1:100.04 ± 0.01
pNLuc/20LK/73EK/82AT0.03 ± 0.01
  • a pNLuc and/or pNLuc/20LK/73EK/82AT were cotransfected into 293T cells with the ampho-MuLV Env expression vector pSVAMLVenv. Transfections were performed with a total of 5 μg of molecular clone DNA at the indicated ratios, with 5 μg of pSVAMLVenv. Virus stocks were harvested and normalized for RT activity, and infectivity was quantitated by luciferase assay after infection of H9 cells. Data are averages from at least six independent assays ± standard error.