ZFYVE1, also known as DFCP1, is a zinc-finger FYVE domain-containing protein. It is involved in autophagy-related processes, innate immune responses, and may play a role in maintaining tissue homeostasis. In autophagy, it is associated with the biogenesis of autophagosomes, and in the innate immune system, it participates in regulating antiviral responses and TLR3-mediated signaling [2,3,4,5,6].

In terms of functional studies using gene knockout models, Zfyve1-deficiency promoted MDA5-but not RIG-I-mediated transcription of downstream antiviral genes. Zfyve1 -/- mice were significantly protected from lethality induced by encephalomyocarditis virus (EMCV) sensed by MDA5, while Zfyve1 -/- and Zfyve1+/+ mice had comparable responses to vesicular stomatitis virus (VSV) sensed by RIG-I. Mechanistically, ZFYVE1 interacted with MDA5, bound to viral RNA, and decreased the ligand binding and oligomerization of MDA5 [1]. Also, Zfyve1 -/- mice were less susceptible than wild-type mice to inflammatory death induced by the synthetic TLR3 ligand poly(I:C) but not LPS, as ZFYVE1 promoted the transcription of downstream antiviral genes upon poly(I:C) stimulation and was associated with TLR3, increasing its binding affinity to poly(I:C) [6].

In conclusion, ZFYVE1 serves as a crucial regulator in both autophagy and innate immune responses. Gene knockout mouse models have revealed its specific roles in antiviral innate immunity, especially in differentiating between MDA5-and RIG-I-mediated responses, as well as in TLR3-mediated signaling. Understanding ZFYVE1's functions can provide insights into the mechanisms of antiviral defense and inflammatory responses, potentially contributing to the development of strategies for treating related diseases.