title: Helicoverpa armigera nucleopolyhedrovirus occlusion-derived virus-associated protein, HA100, affects oral infectivity in vivo but not virus replication in vitro.
abstract: ORF100 (ha100) of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) has been reported as one of the unique genes of group II alphabaculoviruses encoding a protein located in the occlusion-derived virus (ODV) envelope and nucleocapsid. The protein consists of 510 aa with a predicted mass of 58.1 kDa and is a homologue of poly(ADP-ribose) glycohydrolase in eukaryotes. Western blot analysis detected a 60 kDa band in HearNPV-infected HzAM1 cells starting at 18 h post-infection. Transient expression of GFP-fused HA100 in HzAM1 cells resulted in cytoplasmic localization of the protein, but after superinfection with HearNPV, GFP-fused HA100 was localized in the nucleus. To study the function of HA100 further, an ha100-null virus was constructed using bacmid technology. Viral one-step growth curve analyses showed that the ha100-null virus had similar budded virus production kinetics to that of the parental virus. Electron microscopy revealed that deletion of HA100 did not alter the morphology of ODVs or occlusion bodies (OBs). However, bioassays in larvae showed that the 50 % lethal concentration (LC(50)) value of HA100-null OBs was significantly higher than that of parental OBs; the median lethal time (LT(50)) of ha100-null OBs was about 24 h later than control virus. These results indicate that HA100 is not essential for virus replication in vitro. However, it significantly affects the oral infectivity of OBs in host insects, suggesting that the association HA100 with the ODV contributes to the infectivity of OBs in vivo.
authors.affiliation: State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Sijiani
authors.initials: S
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Faculty of Biosciences, Nanjing Normal University, Nanjing 210097, PR China.|State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Xushi
authors.initials: X
authors.lastname: Xu
authors.affiliation: Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors.forename: Marcel
authors.initials: M
authors.lastname: Westenberg
authors.affiliation: Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors.forename: Just M
authors.initials: JM
authors.lastname: Vlak
authors.affiliation: State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Hualin
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Virology and CAS Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Deng
mesh_terms: D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000821:virology; D015967:Gene Expression Regulation, Viral; D007181:Inclusion Bodies, Viral; D045586:Intranuclear Inclusion Bodies / Q000821:virology; D008969:Molecular Sequence Data; D009036:Moths; D017924:Nucleopolyhedroviruses / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D021381:Protein Transport; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D057074:Virus Release; D014779:Virus Replication
chemical_list: D014764:Viral Proteins