Completion of the HIV-1 replication cycle by uDNA via coinfection with an integrating virus. Jurkat cells were infected with D116N-GFP virus only, washed and incubated with protease to remove residual virus, then 2 days later the resulting culture supernatants were used to infect Jurkat-Tat target cells. A. Cells containing only uDNA show little infectious virus output. B. Cells that were coinfected with WT-DsRedX and D116N-GFP viruses and treated with HIV-1 protease inhibitor Indinavir show little virus output. C. Procedures followed as in B, except no Indinavir was present. Virus transfer to Jurkat-Tat target cells results in both DsRedX fluorescence and GFP fluorescence, indicating that infectious viruses were generated which package and deliver functional genomes derived from unintegrated D116N-GFP DNA within the producer cells. Data are representative of multiple independent experiments. "C = 3%", "W", "G", "R" refer to figure 5.