TAT and infection: When MDCK cells were infected with a TAT-Kα2-treated influenza virus (A/Puerto Rico/8/34, PR8) expressing green fluorescent protein (PR8-GFP), infection of the MDCK cells was strongly diminished relative to infection with untreated virus or virus treated with the TAT peptide fused to a scrambled-sequence peptide (TAT-scramble; Fig. S1A; see Table 1 for the peptide sequence).