Study On Regulation Of DNA Sensing Pathway And Interferon Pathway By Golgi Membrane Transmembrane Protein 73

Golgi membrane protein 73(GP73)was first discovered by Kladney et al.In 2000.GP73 is a transmembrane protein located on the Golgi apparatus with a molecular weight of 73 kDa.A large number of studies on GP73 remain in the study of the specificity and sensitivity of GP73 as a marker of liver cancer serum,the role of GP73 in viral infection,cytokine regulation,and the role of cell signaling pathways involved in the study still very vague.Nucleic acid is critical for the replication and reproduction of most viruses,and the detection of abnormal DNA and RNA has evolved into the basic mechanism of host defense against pathogens.In the cGAS-STING cytosolic DNA sensing pathway,DNA receptor cGAS can produce cGAMP as a second messenger,and then the second messenger binds directly to STING to activate downstream signaling.Therefore,this study explored the function of GP73 in the context of DNA virus pathway and the role of GP73 in the downstream pathway of interferon.To activate the natural immune,we must first activate the ISRE promoter,so we designed a luciferase assay to determine whether GP73 affects the ISRE promoter.Our results show that GP73 could significantly inhibit TRIF,MAVS,STING,TBK1-mediated ISRE promoter.We analyzed that the role of GP73 in the cGAS-STING pathway is highly likely to be similar to that in the RNA pathway.In this study,we first explored the role of GP73 in cGAS-STING host DNA pathway,identified the direct interaction between GP73 and STING,and GP73 did not affect the stability of STING.Interferon pathway is a key component of host response to viral infection.Today,interferon has also been widely used in the clinical treatment of viral diseases.Once the interferon pathway is activated,downstream effector proteins are also induced to express.The JAK-STAT signaling pathway is the main effector;its main function is the activation of transcription factors,which induced ISG transcription.At present,we mainly study the function of GP73 in hepatocyte cell line,so we chose HepG2 cells.HepG2 cell lines stably expressing GFP or GP73 were constructed by lentivirus packaging technique.Under the IFNa stimulation,we detected that GP73 can significantly inhibit the downstream of interferon effect protein and antiviral effect of protein expression,further shows that GP73 should be a natural immune negative control factor.