TUFM and infection: Human A549 cells were used for initial viral growth kinetic studies, and A549 cells treated with TUFM siRNA (si-TUFM), si-TUFM plus the FLAG-tagged TUFM plasmid (TUFM-FLAG, for overexpression of TUFM), or a negative control (NC) were, respectively, infected with either rWSN PB2627K or PB2627E at a multiplicity of infection (MOI) of 0.001 or 2 (Fig. 3A to F).