Fig 3.

Effect of N-glycan removal on viral entry. (A and B) Relative entry levels of NiV-F/G-pseudotyped VSV-Renilla luciferase reporter viruses (VSV-rLuc). NiV-F and the indicated wild-type or individual (A) or double (B) N-glycan mutant NiV-G glycoproteins were pseudotyped onto luciferase reporter viruses as described in Materials and Methods. RLU were quantified 18 to 24 h postinfection and plotted against the number of viral genomes per ml. The relative amounts of genome copies in the viral preparations were analyzed by quantitative reverse transcription-PCR as described in Materials and Methods. The data shown are averages ± the standard deviations from three or more independent experiments. Sometimes the standard deviation bars are not visible because they are too small to be seen in a logarithmic scale. *, Mutants for which P values calculated using the Student t tests showed statistically significant differences (P < 0.05) between the wild-type and mutant levels of viral entry at several given genome copy numbers. (C) Western blot analysis of wild-type or mutant NiV-G glycoproteins contained in viral preparations used in panels A and B and blotted with a mouse anti-HA MAb, as described in Materials and Methods. One representative image out of three independent experiments is shown. –, Vector control.