Screening And Identification Of VISA Interacting Proteins

The infection of a virus is a great threat to host;the innate immune system is set up as the natural protection system of an organism.VISA(also known as MAVS,CARDIF,IPS-1),is an critical adapter protein required for virus-triggered IFN-? signaling,recruiting RIG-I-like receptors(including RIG-I and MDA5)and downstream signaling proteins to VISA signalosome at mitochondria upon virus infection,leading to activation of transcriptional factor IRF3 and NF-?B,and resulting in the induction of IFNs and other inflammatory cytokines.It is shown that VISA is critically involved in both virus-triggered TLR3-independent and TLR3-mediated antiviral IFN signaling.However,the mystery of VISA for the antiviral function is still not completely figured out.In this study,VISA are used as bait for screening a human 293 T cell cDNA library in a yeast two-hybrid screening,trying to identify the interacting proteins of VISA.Then,coimmunoprecipitation experiments are used to verify the association between VISA and candidates proteins screened from the yeast two-hybrid system assay.It indicated that Sec13L1 associated with VISA.Overexpression of Sec13L1 in 293 cells facilitated to enhance the activation of IFN? promoter induced by VISA and virus infection in a dose-dependent manner.