title: Characterization of a novel envelope protein (VP281) of shrimp white spot syndrome virus by mass spectrometry.
abstract: The primary structure of a novel envelope protein from shrimp white spot syndrome virus (WSSV) was characterized using a combination of SDS-PAGE and mass spectrometry. The resulting amino acid sequence matched an open reading frame (ORF), ORF1050, of the WSSV genome ORF database. ORF1050 contained 843 nt, encoding 281 aa, and was termed the vp281 gene. Computer-assisted analysis showed that both the vp281 gene and its product shared no significant homology with other known viruses. However, they shared striking identity/similarity with another WSSV structural protein, VP292, at both the nucleotide and amino acid sequence level, suggesting that vp281 and vp292 might have evolved by gene duplication from a common ancestral gene. WSSV VP281 cDNA was cloned into a pET32a(+) expression vector containing a T7 RNA polymerase promoter to produce (His)(6)-tagged fusion proteins in Escherichia coli strain BL21. Specific mouse antibodies were raised using the purified fusion protein (His)(6)-VP281. Western blot analysis showed that the mouse anti-(His)(6)-VP281 antibodies bound specifically to VP281 of WSSV, without cross-reactivity with VP292. The transmission electron microscope immunogold-labelling method was used to localize VP281 in the WSSV virion as an envelope protein. The cell attachment 'Arg-Gly-Asp' motif in VP281 indicated that this protein might play an important role in mediating WSSV infectivity.
authors.affiliation: Tropical Marine Science Institute, National University of Singapore, Singapore 1192602.|Department of Biological Sciences, National University of Singapore, Singapore 1175431.
authors.forename: Canhua
authors.initials: C
authors.lastname: Huang
authors.affiliation: Tropical Marine Science Institute, National University of Singapore, Singapore 1192602.|Department of Biological Sciences, National University of Singapore, Singapore 1175431.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Tropical Marine Science Institute, National University of Singapore, Singapore 1192602.|Department of Biological Sciences, National University of Singapore, Singapore 1175431.
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Lin
authors.affiliation: Key Laboratory of Marine Biotechnology, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, People's Republic of China3.
authors.forename: Xun
authors.initials: X
authors.lastname: Xu
authors.affiliation: Tropical Marine Science Institute, National University of Singapore, Singapore 1192602.|Department of Biological Sciences, National University of Singapore, Singapore 1175431.
authors.forename: Choy-L
authors.initials: CL
authors.lastname: Hew
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western / Q000379:methods; D004267:DNA Viruses / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D004279:DNA, Viral; D033364:Decapoda / Q000821:virology*; D005814:Genes, Viral; D006639:Histidine; D016253:Microscopy, Immunoelectron / Q000379:methods; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014759:Viral Envelope Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology
chemical_list: D004279:DNA, Viral; D011993:Recombinant Fusion Proteins; D014759:Viral Envelope Proteins; D006639:Histidine