RIGI and viral infectious disease: Morever, although USP5 reportedly increases K11- and K48-linked ubiquitination of RIG-I upon virus infection and thereby facilitates the degradation of RIG-I (40), the detailed mechanism used by USP5 to enhance K11-linked Ub chains of RIG-I and the exact functions of K11-linked Ub chains implicated in the RIG-I-mediated signaling pathway remain elusive.