CCR5 structural plasticity shapes HIV-1 phenotypic properties
Fig 2
Different HIV-1 gp120s show different modes of binding to CCR5.
The panels show competition binding experiments of 10 nM 35S-gp120 #34 to HEK-R5 membranes by increasing concentrations of unlabeled gp120 #34 (A), #58 (A), #50 (B) and #10 (C). In all experiments, unlabeled gp120 #25 was used as an internal control (A, B and C). Representative experiments out of 3 independent experiments performed in duplicate are shown. Results (means ± SEM) were normalized for non-specific binding (0%) and specific binding in the absence of competitor (100%, B0). In the panels, data points are fitted according to a one-site (gp120 #25, 34 and 58) or a two-site (gp120 #50, F value = 43.9; p < 0.0001) competitive binding model or a sigmoidal dose-response model with a variable slope (gp120 #10). The Hill slope (nH) values were deduced from fitting of the competition curves according to a sigmoidal dose-response model with a variable slope.