Inhibits host NF-kappa-B activation stimulated by IL-1 and multiple PRR viral detection pathways. Targets host NF-kappa-B component RELA/p65 for ubiquitin-dependent proteasomal degradation. Interacts with host RELA (via RHD domain), ELOB, ELOC and CUL5; these interactions induce the proteasomal degradation of host RELA.