FIG 1.

SUN1 overexpression inhibits HIV-1 infection. (A to C) Plasmids expressing Flag-tagged or untagged SUN1 were transfected into HEK293A cells together with plasmids expressing CD4 and CCR5 or CXCR4. A plasmid expressing renilla luciferase was included to serve as a control for transfection efficiency and sample handling. At 48 h posttransfection, cells were infected with NL4-3luc vectors pseudotyped with the indicated HIV-1 envelopes. At 48 h postinfection, luciferase activities were measured. The firefly luciferase activity was normalized to the renilla luciferase activity. Control cells or HEK293A cells stably expressing SUN1-Flag were infected with VSV_G-pseudotyped NL4-3luc. At 48 h postinfection, luciferase activities were measured. Data presented are means and SD for three independent experiments. Protein levels in the cell lysates were analyzed by Western blotting. **, P < 0.005; ***, P < 0.001. (D) MT4 cells were infected with the replication-competent NL4-3 virus. At 2 and 4 days postinfection, the viral protein levels in the cell lysates were measured by Western blotting. EV, MT4 cells transduced with an empty lentivector; SUN1, MT4 cells transduced with a lentivector expressing SUN1-Flag.