Fig 3.

Roles of PARP-1 in the expression of avian Rous-associated virus type 1 and in HIV-1 infection of human cells. (a) Reverse transcriptase activity detected in the 20% sucrose cushion-concentrated cell culture supernatant derived from DT40 WT, KO, and h-1 cells. The reverse transcriptase activity was normalized to the total number of viable producer cells. The SD represents triplicate measurements from one experiment. These results are representative of four independent experiments. (b) Levels of PARP-1 protein in control (WT) and PARP-1-knockdown (KD) human CD4⁺ T cells. Alpha tubulin was detected in these samples as a loading control. (c) Susceptibility of control and PARP-1 knockdown human CD4⁺ T cells to HIV-1 infection. The luciferase levels detected in these cells were normalized to the ATP amounts to calculate infectivity. The standard deviation values represent the variability observed in one experiment. The experiment is representative of two independent experiments.