TABLE 2.

Fusion activity of rSV5 harboring F protein cytoplasmic tail truncationsa

VirusAvg relative CAT activity ± SD
Mock10 ± 9
rSV54,775 ± 83
rSV5 FΔ24,651 ± 69
rSV5 FΔ84,459 ± 220
rSV5 Fd104,388 ± 108
rSV5 FΔ123,841 ± 191
rSV5 FΔ144,116 ± 66
rSV5 FΔ163,591 ± 171
rSV5 FΔ183,660 ± 102
  • a BSR T7/5 cells were infected with wt rSV5 or the indicated rSV5 F cytoplasmic tail-truncated viruses. In parallel, BHK-21F cells were transfected with the plasmid pBH82 (23), which encodes CAT under the control of the T7 RNA polymerase promoter. At 16 h p.i. or p.t., the BHK-21F cells were trypsinized and overlaid onto the BSR T7/5 cells. At 24 h p.i. or p.t., CAT activity was measured as described in Materials and Methods. Each CAT assay was performed in triplicate.