MT-RNR2 and infection: Compared to the wt CI, the viruses bearing all the mutated HNs show more infected cells in the CV-1 cell monolayers after 3 days (Fig. 7A, arrows point to examples of individual infected cells); contrast wt CI-1 infection in the top photo to infection with viruses bearing individual HN mutations in the subsequent photos, where these adaptations confer superior growth in cultured cells as expected.