FIG 3.

WT PrV gB ectodomain interactions with liposomes. (A) WT gB ectodomains bind to the DOPC-CH liposomes. The presence (+) of liposomes (L) and protein is indicated. Aliquots of the top (t), i.e., liposome, and bottom (b), i.e., unbound protein, fractions were analyzed by SDS-PAGE, and the Strep-tag present on gB was detected by WB using Streptactin-HRP conjugate. The WT protein is found in the top fraction only in the presence of liposomes with 60% DOPC and 40% CH. (B) Coflotation of WT gB and DOPC liposomes with increasing amounts of cholesterol. The liposome composition is indicated at the top. gB is detected in the top fraction only when 40% CH is present. (C) Coflotation of WT gB and liposomes made of combinations of lipids found in the plasma membrane. The CH concentration was fixed at 40% or 0% (top and bottom, respectively), and one or two more lipids were added, resulting in a total of 5 lipid compositions. The protein was detected bound to all of the CH-containing liposomes, while it was found in the unbound fraction in the absence of CH.