MuSOX expression and PABPC or HA-muSOX localization were analyzed as described previously [16, 23] . Briefly, NIH 3T3, HEK293T, or COS7 cells were grown on coverslips, and infected with MHV68 variants or transfected with HA-muSOX variants. Cells were then stained with rabbit polyclonal anti-muSOX (1:25 dilution), mouse monoclonal anti-PABPC 10e10 (1:25 dilution) (Santa Cruz Biotechnology), or mouse monoclonal anti-HA (1:500 dilution) (Abcam) and AlexaFluor 546-or 488-conjugated goat anti-mouse or goat anti-rabbit secondary antibody (1:1500). Coverslips were mounted in DAPI-containing Vectashield mounting medium (Vector Labs) to stain cell nuclei.