FIG. 7.

Nuclear import and export. (a) Nuclear localization of IRF-2. Cells were transfected with plasmid pEGFP-C1-hIRF-2 for 24 h and then superinfected with SARS-CoV for 16 h (right panel) or left uninfected (left panel). Viral N protein was detected with a specific rabbit antiserum and a Cy3-conjugated secondary antibody. (b) Nuclear export assays. Cells were transfected with the Rev expression construct pcRev, the Rev export-dependent CAT reporter plasmid pDM128 (19), and the Renilla luciferase control plasmid pRL-SV40. After 4 h at 37°C, cells were either infected with SARS-CoV or left uninfected (black columns). As a control, cells were treated in parallel with the CRM-1 inhibitor leptomycin B (LMB) at a concentration of 2 ng/ml (grey columns). At 16 h postinfection, reporter activities were measured. CAT activities were normalized to the corresponding Renilla luciferase activities to determine induction. Data from a representative experiment are shown.