Figure 4
From: The prototype foamy virus protease is active independently of the integrase domain
Co-expression of a mutated GagPol fusion protein with an inactive PR domain together with a GagPR-RT fusion protein leads to both maturated Gag and Pol proteins and viral infectivity. (A) Scheme of the plasmids used in this experiment. (B) Western blot from both transfected cells (upper three panels) and partially purified viruses (lower panel) using αGag and αPol monoclonal antibodies. HEK 293 T cells were transfected with pMD9, pcoPE and pcoPG4 and either pGagPol (lane 1) or a combination of pGagIN and pGagPR-RT (lane 2) or pGagIN and pGagPolD/A (lane 3). The transfected DNA amounts are indicated in [μg]. Determination of cellular GAPDH amounts served as loading control. (C) Viral titers were determined on BHK-ll indicator cells. Transfections were performed in triplicate assays. The error bars represent the standard deviation. The transfected DNA amounts are indicated in [μg].