ADAR and infection: For expression of ADAR and APOBEC genes in HTBE cells infected with H1N1, H3N2, or H5N1 (Fig. 4), we found that ADAR1 expression increased dramatically along the course of infection for H1N1 and H3N2, but not H5N1, which was consistent with the changes of A-to-I RNA editing levels in H1N1, H3N2, and H5N1 infected cells.