Table 2.
Properties of mutated gH proteins and virus mutantsa
| Mutant | Substituted aa (affected element) | In vitro fusion (+gB, gD, gL) | Cell-to-cell spread | Penetration |
|---|---|---|---|---|
| gH (WT) | None | ++++ | ++++ | ++++ |
| gHT550A | T550 → A550 (flap) | ++++ | ++++ | NT |
| gHD551A | D551 → A551 (flap) | ++++ | ++++ | NT |
| gHP554A | P554 → A554 (flap) | ++++ | +++ | NT |
| gHE555A | E 555→ A555 (flap) | ++++ | ++ | ++++ |
| gH550/4A | T550 → A550 (flap) | + | ++ | ++++ |
| D551 → A551 | ||||
| P554 → A554 | ||||
| E555 → A555 | ||||
| gHC547S | C547 → S547 (ΔSS3) | ++ | + | +++ |
| gHC571S | C571 → S571 (ΔSS4) | − | + | + |
| gHC573S | C573 → S573 (flap) | ++++ | +++ | ++++ |
| gHE555S | E555 → S555 (flap) | ++++ | +++ | NT |
| gHV630C | V630 → C630 (HP) | ++++ | ++++ | NT |
| gHE555C/V630C | E555 → C555 (+ SS5a) V630 → C630 | + | + | + |
| gHS556C | S556 → C556 (flap) | ++++ | +++ | NT |
| gHV631C | V631 → C631 (HP) | ++++ | ++++ | NT |
| gHS556C/V631C | S556 → C556 (+ SS5b) V631 → C631 | + | + | ++ |
| gHN627Q | N627 → Q627 (Δ NAG) | +++ | +++ | ++++ |
| gH630/4A | V630 → A630 (HP) | + | ++ | ++ |
| V631 → A631 | ||||
| L633 → A633 | ||||
| L634 → A634 | ||||
| No gH | − | − | NT |
a
Efficiency of the mutated gH proteins in fusion assays performed in plasmid-transfected RK13 cells, as well as plaque formation and entry kinetics in RK13 cells infected with corresponding PrV mutants, were roughly quantified (++++ to −); gH mutations entailing severe defects with respect to in vitro fusion and/or virus replication are highlighted. Abbreviations: SS, disulfide bridge; HP, hydrophobic patch; NAG, N-glycosylation; NT, not tested; WT, wild type.