TABLE 3.
Redundant roles of K500 and T582 in mediation of X-MLV infections by the M. dunni X-receptor
| X-receptor assayedb | Titer of LacZ pseudotype (CFU/ml)a
|
|
|---|---|---|
| MCF247 | X-MLV (NZB) | |
| None | 0 | 0 |
| M. dunni | 6.1 × 102 | 1.5 × 102 |
| Single substitutions | ||
| D590N | 1.7 × 102 | 3.8 × 102 |
| K500E | 1.1 × 103 | 4.0 × 101 |
| D469N | 1.2 × 103 | 1.4 × 102 |
| Double mutations | ||
| D590N-T582Δ | 7.4 × 102 | 2.0 × 102 |
| K500E-T582Δ | 1.8 × 103 | 0 |
| D469N-T582Δ | 2.0 × 102 | 3.2 × 102 |
| Triple mutations | ||
| K500E-T582Δ-D590N | 4.6 × 102 | 0 |
| D469N-T582Δ-D590N | 4.2 × 102 | 7.7 × 102 |
a
Infectivity assays for the LacZ(MCF) virus were done in CHO cells, whereas those for LacZ(X-MLV) were done in BALB/3T3 fibroblasts because of the zero backgrounds of infections in these control untransfected or mock-transfected cells (Tables 1 and 2). The results are averages of three independent assays.