Fig. 8

The conserved glutamic acid residue within the hinge region of Vpu modulates the protein functions. a Logo plots demonstrating the amino acid conservation at each position within the 28EYRKIL33 transmembrane-proximal hinge region of Vpu isolates from HIV-1 Clade B (left panel) as well as from all HIV-1 clades (right panel) [49]. b, c CD4 degradation mediated by E28 single-point mutants. b A representative Western Blot indicating steady state levels of CD4 following co-transfections of HEK293T cells with a CD4 expressor and the indicated proviral constructs. c Quantitative densitometric analyses of efficiency of Vpu mutants to degrade CD4 from a compilation of five independent experiments. d, e E28 is important for efficient enhancement of virus release in HeLa cells transfected with proviral constructs encoding Vpu single-point mutations. d A representative Western blot showing the amount of virion-associated p24 released into the supernatant (virion) and Gag products (p24 and p55) in the cell lysate. e A summary of the efficiency of virus release (quantified and expressed as mentioned in Fig. 4 legend) from five different experiments. For both (c) and (e), the error bars represent SD. Statistical analyses were performed using a two-way ANOVA, Tukey’s multiple comparison test