Fig. 5.

Complementation of a recombinant virus expressing M2Ala67-79. MDCK (A), M2Ud-expressing (B), and M2UdAla67-69-expressing (C) cells were infected with the indicated recombinant viruses at an MOI of 0.001. At the indicated hpi, cell supernatants were collected and the numbers of infectious virus particles were determined by TCID₅₀ assay on cells expressing wild-type M2. The means and standard errors of the means for triplicate samples from a representative experiment are shown. The limit of detection is marked by a horizontal dotted line. (D) MDCK cells were infected with the indicated recombinant viruses at an MOI of 0.5. At 16 hpi, expression in cell lysates of M2 and the cell protein loading control, β-actin, was compared by Western blotting.