Fig. 1

2-thio-6-azauridine inhibits Vpu-mediated down-regulation of cell surface BST-2. a Illustration of the assay that was used to screen small molecules that antagonize HIV-1 Vpu function and inhibit BST-2 degradation. b Structure of 2-thio-6-azauridine. c HeLa and HeLa-Vpu cells were treated by 2-thio-6-azauridine for 24 h. Levels of cell surface BST-2 were detected using cell-ELISA (left panel), flow cytometry (middle pannel) or Western blotting (right panel) (d) HeLa-Vpu and HeLa cells were treated with increasing concentrations of 2-thio-6-azauridine (0.05, 0.5, 5 µM) for 24 h. Cell surface BST-2 was measured using cell-ELISA. (e) HeLa and HeLa-Vpu cells were treated with DMSO, 2-thio-6-azauridine (5 µM) and ConA (50 nM) for 24 h respectively. The amounts of bst-2 mRNA were measured by real-time RT-PCR. The bst-2 mRNA values are normalized to those in the control cells that were treated with DMSO. f HeLa-Vpu cells were treated with DMSO, 2-thio-6-azauridine (5 µM) and ConA (50 nM) for 24 h respectively. Western blots of cell lysates were probed with anti-Vpu (top panel) and anti-β-actin (bottom panel) antibodies, respectively. (*p < 0.05, t test)