FIG 3.

NS1 does not reduce mitochondrial membrane potential. (A) HeLa cells were transfected with an expression plasmid encoding influenza virus PB1-F2 or myc-tagged NS1. Twenty-four hours later, cells were stained with anti-myc, anti-PB1-F2, and anti-Tom20 (mitochondrion marker) antibodies and analyzed by confocal microscopy. Nuclei were visualized by staining with DAPI. (B) HEK293T cells were treated with CCCP (40 μM) or transfected with an expression plasmid encoding influenza virus PB1-F2 or NS1. Twenty-four hours later, the cells were stained with TMRM and analyzed by flow cytometry. Similar results were obtained in three separate experiments. max, maximum.