title: Mutational and functional analysis of N-linked glycosylation of envelope fusion protein F of Helicoverpa armigera nucleopolyhedrovirus.
abstract: The envelope fusion (F) protein of baculoviruses is a heavily N-glycosylated protein that plays a significant role in the virus infection cycle. N-Linked glycosylation of virus envelope glycoprotein is important for virus envelope glycoprotein folding and its function in general. There are six predicted N-glycosylation sites in the F (HaF) protein of Helicoverpa armigera nucleopolyhedrovirus (HearNPV). The N-glycosylation site located in the F(2) subunit (N104) of HaF has been identified and functionally characterized previously (Long et al., 2007). In this study, the other five potential N-glycosylation sites located in the HaF1 subunit, namely, N293, N361, N526, N571 and N595, were analysed extensively to examine their N-glycosylation and relative importance to the function of HaF. The results showed that four of these five potential glycosylation sites in the F(1) subunit, N293, N361, N526 and N571, were N-glycosylated in F proteins of mature HearNPV budded viruses (BVs) but that N595 was not. In general, the conserved site N526 was critical to the functioning of HaF, as absence of N-glycosylation of N526 reduced the efficiency of HaF folding and trafficking, consequently decreased fusogenicity and modified the subcellular localization of HaF proteins, and thus impaired virus production and infectivity. The absence of N-glycosylation at other individual sites was found to have different effects on the fusogenicity and subcelluar distribution of HaF proteins in HzAM1 cells. In summary, N-glycosylation plays comprehensive roles in HaF function and virus infectivity, which is further discussed.
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Shu
authors.initials: S
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Manli
authors.initials: M
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.|Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, The Netherlands.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Shufen
authors.initials: S
authors.lastname: Li
authors.affiliation: Laboratory of Virology, Wageningen University, The Netherlands.
authors.forename: Monique M
authors.initials: MM
authors.lastname: van Oers
authors.affiliation: Laboratory of Virology, Wageningen University, The Netherlands.
authors.forename: Just M
authors.initials: JM
authors.lastname: Vlak
authors.affiliation: Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, The Netherlands.
authors.forename: Ineke
authors.initials: I
authors.lastname: Braakman
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Fei
authors.initials: F
authors.lastname: Deng
authors.affiliation: State Key Laboratory of Virology, and Joint Laboratory of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PRChina.
authors.forename: Hualin
authors.initials: H
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D006031:Glycosylation; D007915:Lepidoptera / Q000821:virology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D017924:Nucleopolyhedroviruses / Q000235:genetics* / Q000472:pathogenicity; D010449:Peptide Mapping; D017510:Protein Folding; D011499:Protein Processing, Post-Translational; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D014760:Viral Fusion Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014774:Virulence
chemical_list: D021122:Protein Subunits; D014760:Viral Fusion Proteins