Screening And Function Analysis Of Host Molecules Interacting With Bunyaviral Nucleoproteins

Bunyavirus is a negative segmented single-stranded RNA virus,containing a large number of widely distributed,highly pathogenic,high risk pathogens while currently not targeted vaccines and drugs were built.SFTSV(Severe fever with thrombocytopenia syndrome virus)is a newly discovered virus first isolated and identified in China,and CCHFV(Crimean-Congo hemorrhagic fever virus)is a level-4biosafety virus with extremely high lethality rate and has attracted worldwide attention.Both of them pose a great threat to human health and socioeconomic safety.Nucleocapsid protein(NP)plays an important role in the life cycle of Bunyavirus.In addition to forming the nucleocapsid structure together with RNA-dependent RNA polymerase(Rd Rp),it may also perform a variety of potential functions beneficial to viral replication through interaction with the host factors,and is usually an important antiviral target by the host.However,there is still a lack of research on how and which host factors interacts with NP.This study mainly focuses on the NP proteins of SFTSV and CCHFV.By affinity purification and liquid mass spectrometry(LC-MS),we identified and screened a number of host proteins possibly interacting with NP.Then,with bioinformatic analysis on their function and pathways,such as the GO and KEGG analysis,we found that the host factors are mainly related to the ribosome structure component,protein translation,protein folding functions,etc.Subsequently,we selected the proteins strongly interacting with NP,constructed their expression plasmids,and then preliminarily examined the effects of these genes on SFTSV/CCHFV replication through the SFTSV and CCHFV minigenome reporting system.Through detection,it was found that,compared with negative control,overexpression of the host factors had significant influence on the reporter expression level of SFTSV and CCHFV minigenome systems under different methods.In summary,our research established the interactome of SFTSV and CCHFV NP proteins and preliminarily revealed the probable roles of the identified host factors potentially interacting with these viral proteins in the virus replication.These findings may have great guiding significance to comprehensively understand the influences of host factors in bunyavirus infection and to promote targeting drug design in the future.