TABLE 1.
Fusion/CSE ratios for WT NiV-F and the N-glycan mutant proteinsa
| NiV-F Env | Fusion/CSE ratio |
|---|---|
| F | 1 |
| F2 | 1 |
| F3 | 6.5 |
| F4 | 1.9 |
| F5 | 3.4 |
| F2F3 | 4.8 |
| F2F4 | 6.8 |
| F2F5 | 4.4 |
| F3F4 | 17.7 |
| F3F5 | 6.6 |
| F4F5 | 8.6 |
| F2F3F5 | 3.9 |
| F2F4F5 | 47.3 |
| F2F3F4F5 | 4.6 |
a
The fusogenicity and cell surface expression of the N-glycan mutants were within the linear range of our assay described for Fig. 2B to E. Therefore, a reasonable indicator of fusogenicity that takes into account the differential expression levels among the various N-glycan mutants is the fusion-to-CSE ratio. Both fusion (nuclei in syncytia per field) and CSE (mean channel fluorescent intensity) levels of the N-glycan mutants were normalized to that of WT NiV-F, which was set at 100%. The ratios of the normalized fusion and CSE values for each mutant were then calculated. By definition, the fusion and CSE ratio for WT NiV-F would be 1.0 (100%/100%).