(a) After a 24 hr infection, total infected Vero cell lysates were collected and proteins were separated by SDS polyacrylamide gel electrophoresis (SDS-PAGE). Blot was probed with anti-VSV-N and anti-VSV-GIN CT, which does not recognize GNJ. IN: rVSV-EnvG4-G6IN; NJ: rVSV-EnvG4-G6NJ. (b-d) Sucrose-gradient purified rVSV-EnvG4-G6 particles were separated by SDS-PAGE. (b) Blots of 106 pfu of rVSV-EnvG4-G6IN and 2.5×106 pfu rVSV-EnvG4-G6NJ vectors were probed separately for EnvG using anti-gp120. (c) Blot of 106 pfu rVSV-EnvG4-G6IN was probed with anti-VSV-GIN CT. (d) Blot of 106 pfu rVSV-EnvG4-G6IN and rVSV-EnvG4-G6NJ was probed with anti-VSV-G. (e) Replication kinetics of rVSV-EnvG4-G6 and rVSV-G4 viruses in Vero cells. Vero cells were infected in 6-well plates at an MOI of 0.1. At various intervals post infection, supernatant was collected from duplicate wells and virus was titrated. Plaques were counted manually after cell fixation.