Plays a role in virus cell tropism, and may be required for efficient virus replication in macrophages. Inhibits also the host cGAS/STING-mediated type I interferon production by inducing host IRF3 degradation through the proteasome pathway. Interacts with host IRF3 and TRIM21; these interactions mediates degradation of IRF3 through TRIM21 and ubiquitin-meditated proteolysis. Belongs to the asfivirus MGF 360 family.