Figure 1

EB2 surface expression and NiV glycoprotein-mediated cell-to-cell fusion in HeLa cells transfected with different amounts of pCAGGS-EB2. (A) Receptor-negative HeLa cells were transfected with the indicated quantities of an EB2-encoding pCAGGS vector. At 24 h p.t., immunostaining was performed using recombinant EphB4/Fc and rhodamine-conjugated secondary antibodies. Nuclei were visualized by DAPI staining. (B) HeLa cells expressing different amounts of EB2 were incubated with an EB2-specific antibody followed by FITC-conjugated secondary antibodies. FACS analysis was performed at 24 h p.t. (C) HeLa cells were cotransfected with constant quantities of plasmids carrying the NiV F and G genes and the indicated amounts of pCAGGS-EB2. To visualize cell-to-cell fusion, cells were fixed and incubated with Giemsa staining solution at 24 h p.t.. Representative microscopic fields were photographed. (D) Syncytium formation of HeLa cells expressing different amounts of EB2 as shown in panel C was quantified by counting and averaging the number of nuclei per syncytium of twenty randomly chosen syncytia.