TABLE 1.
Transforming activities of JSRV and ENTV Env mutants in 208F cells during prolonged culture
| Env protein | Transformed foci per dish at weeka:
|
Titer (AP+ FFU/ml)b | ||||||
|---|---|---|---|---|---|---|---|---|
| 2 | 3 | 4 | 5 | 6 | 7 | 8 | ||
| Jenv-FLAG | 250 | TMTC | 1,600 | |||||
| JSRV-MLV | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 200 |
| JSU-hIgG | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ND |
| Jenv-Y590F-FLAG | 0 | 0 | 1 | 2 | 3 | 5 | 10 | 18 |
| Jenv-Y590D-FLAG | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 120 |
| Jenv-Y590C-FLAG | 0 | 0 | 1 | 3 | 7 | 28 | 50 | 270 |
| Jenv-M593E-FLAG | 0 | 0 | 5 | 10 | 30 | 80 | 105 | 380 |
| Jenv-ΔE584-FLAG | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 200 |
| Jenv-ΔMK588/589-FLAG | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 54 |
| FLAG-Eenv-Y590,2,6F | 0 | 0 | 1 | 10 | 35 | 90 | 125 | ND |
| 10A1 Env | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ND |
a
208F cells were transfected with plasmids encoding the indicated Env proteins, and transformed foci were counted at the indicated times (foci per 2 μg of DNA for Jenv-FLAG [cells were split 1:5 after transfection with 10 μg of DNA] or foci per 5 μg of DNA for all other constructs [cells were split 1:2 after transfection with 10 μg of DNA]). The experiment was repeated once, and similar results were obtained. TMTC, too many to count.
b
Plasmids encoding the indicated Env proteins were used to pseudotype the LAPSN retroviral vector encoding AP, and the titer of the vector on HTX cells is given. ND, not done.