Research On The Expression Characteristics And Antiviral Effect Of Interferon Induced Transmembrane Protein 3

Interferon induced transmembrane proteins 3(IFITM3)is a kind of transmembrane proteins produced by interferon.IFITM3 can inhibit a variety of RNA viruses,such as Influenza virus,Human immunodeficiency virus,Dengue virus,Ebola virus,Zika virus,etc.IFITM3 can resist viruses by affecting the release and replication of viral nucleic acids.As a transmembrane protein,IFITM3 can regulate membrane permeability by changing membrane curvature and cholesterol content of cell membrane or intracellular membrane,thus preventing the genetic material of virus from entering the membrane.The detailed antiviral mechanism of IFITM3 is a hot and difficult point in the current research..IFITM3 is widely expressed in immune tissue,,indicating that the study of IFITM3 has potential feasibility for the development of clinical antiviral drugs.Therefore,it is of great significance to study the functional characteristics and mechanism of IFITM3.In this work,the IFITM3 gene of African green monkey(AGM)was cloned firstly,and the expression difference of IFITM3 protein in different tissues and organs of AGM was detected by Quantitative real-time PCR(q RT-PCR)and immunohistochemistry.The eukaryotic expression-vector of IFITM3 and the overexpression cell lines of IFITM3 were successfully constructed.Then the Murine Norovirus(MNV)and the Severe Fever with Thrombocytopenia Syndrome virus(SFTSV)were used to infect cell lines to verify the inhibitory effect of IFITM3 protein on the replication of viral genes.The main conclusions are as follows:(1)The IFITM3 sequence of AGM has a high similarity and homology with other species IFITM3.Its conserved specific domain and site play an important role in the function of IFITM3.(2)High expression of both IFITM3 gene and protein were detected in the spleen,skin and lymph nodes of AGM,indicating that IFITM3 is an important immune defense weapon..(3)IFITM3 can effectively inhibit the replication of SFTSV gene,but has no significant effect on the replication of MNV gene.It is speculated that SFTSV invaded the host cell with an intranuclear pathway depending on the protein envelope,and SFTSV was interfered by IFITM3 when it fused with the membrane to produce fusion pore to release viral genetic material.However,MNV does not have the protein envelope,which may enable it to produce the escape mechanism for the immune defense line established by the host IFITM3.In conclusion,this paper analyzed the structure and expression characteristics of IFITM3 in AGM,and successfully established the over expression cell line of IFITM3 and verified its antiviral effect,which can provide reference for further study of antiviral spectrum and functional mechanism of IFITM3.