A Myc-tagged expression construct was generated by inserting the cDNA of porcine DDX1 into the pcDNATM3.1/myc-His(–)A vector (Invitrogen, Carlsbad, CA, USA).
The commercial antibodies used in this study include an anti-Myc monoclonal antibody (Santa Cruz Biotechnology, Dallas, TX, USA), an anti-FLAG monoclonal antibody (Santa Cruz Biotechnology), an anti-IRF3 monoclonal antibody (Cell Signaling Technology, Beverly, MA, USA), an anti-P-IRF3 monoclonal antibody (Cell Signaling Technology), an anti-DDX1 polyclonal antibody (Abcam, Cambridge, MA, USA), and an anti-β-actin monoclonal antibody (Santa Cruz Biotechnology). An anti-VP1 polyclonal antibody was prepared in our laboratory (Li et al.2017 (link)). Anti-3D polyclonal antibody (500 μg/mL) was produced in rabbit by immunization with FMDV 3D protein.