E3 ubiquitin ligases, the powerful modulator of innate antiviral immunity.

During viral infection, the innate immune system represents the first defense line of the human body. The pathogen associated molecular patterns (PAMPs) from the viruses are recognized by pattern recognition receptors (PRRs) of the host cell, especially from those of the immune cells. Sensing of PAMPs by PRRs elicits an elegant signal transduction system, ultimately leading to the production of type I interferons (IFNs) and proinflammatory cytokines. Ubiquitination, with its versatile functions, plays a central role in modulating almost every single step of this signaling cascade. Ubiquitin ligases, which catalyze different types of ubiquitination correlating with multiple functions, are the key participant in fine-tuning antiviral signal transduction. In this review, we focus on summarizing the ubiquitin ligases that regulate the key signaling molecules in antiviral innate immunity.