title: Genetic interaction between NS4A and NS4B for replication of Japanese encephalitis virus.
abstract: Flavivirus NS4A and NS4B are important membrane proteins for viral replication that are assumed to serve as the scaffold for the formation of replication complexes. We previously demonstrated that a single Lys-to-Arg mutation at position 79 in NS4A (NS4A-K79R) significantly impaired Japanese encephalitis virus (JEV) replication. In this study, the mutant virus was subject to genetic selection to search for the potential interaction between NS4A and other viral components. Sequencing of the recovered viruses revealed that, in addition to an A97E change in NS4A itself, a Y3N compensatory mutation located in NS4B had emerged from independent selections. Mutagenesis analysis, using a genome-length RNA and a replicon of JEV, demonstrated that both adaptive mutations greatly restored the replication defect caused by NS4A-K79R. Our results, for the first time to our knowledge, clearly showed the genetic interaction between NS4A and NS4B, although the mechanism underlying their interaction is unknown.
authors.affiliation: Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Xiao-Dan
authors.initials: XD
authors.lastname: Li
authors.affiliation: Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Han-Qing
authors.initials: HQ
authors.lastname: Ye
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.|Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Cheng-Lin
authors.initials: CL
authors.lastname: Deng
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.|Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Si-Qing
authors.initials: SQ
authors.lastname: Liu
authors.affiliation: Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Hong-Lei
authors.initials: HL
authors.lastname: Zhang
authors.affiliation: Guizhou Fisheries Research Institute, Guiyang 550025, PR China.
authors.forename: Bao-Di
authors.initials: BD
authors.lastname: Shang
authors.affiliation: Wadsworth Center, New York State Department of Health, Albany, NY, USA.
authors.forename: Pei-Yong
authors.initials: PY
authors.lastname: Shi
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D004252:DNA Mutational Analysis; D004664:Encephalitis Virus, Japanese / Q000235:genetics / Q000502:physiology*; D020125:Mutation, Missense; D025941:Protein Interaction Mapping; D012641:Selection, Genetic; D013489:Suppression, Genetic; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication
chemical_list: C080106:NS4A protein, flavivirus; C080107:NS4B protein, flavivirus; D017361:Viral Nonstructural Proteins