FIG 9.

NoV RdRp-catalyzed RNA synthesis localizes to mitochondria in transfected BSR-T7/5 cells. BSR-T7/5 cells were transfected with pT7-N1-HA and incubated for 19.5 h. Cells were pretreated with Act D for 30 min, then newly synthesized viral RNA was labeled with BrUTP for 4 h in the presence of Act D. At 24 hpt, mitochondria were stained with MTR (red), and cells were fixed and permeabilized. BrU-labeled viral RNA was detected by immunostaining with monoclonal anti-BrdU primary and FITC-labeled secondary antibodies (green; BrU). Merged signals, including DAPI staining of the nuclei (blue), are shown; the yellow signal in the merge image indicates colocalization. Closed arrowheads indicate BrU-labeled viral RNA in transfected cells; open arrowheads indicate untransfected cells. Bar, 10 μm.