FIG. 2.
Polymorphism at position 9 is responsible for the differential localization of the PB2 protein. (A) Alignment of the mitochondrial localization signals of influenza A virus PB2 proteins. (B) Images of cellular distribution of wild-type and mutant PB2 proteins in transfected Vero cells. (C) PB2-expressing cells were scored for mitochondrial localization of PB2. Columns represent the percentage of PB2-expressing cells containing mitochondrial PB2 signal. Bars represent standard errors of the means based on three independent experiments (n = 63 to 110 cells/experiment). **, P < 0.0002; *, P < 0.021 (based on an unpaired, two-tailed Student's t test).