title: Identification of an antibody-binding epitope on the rotavirus A non-structural protein NSP2 using phage display analysis.
abstract: The non-structural protein 2 (NSP2) of rotavirus has important roles in rotavirus replication associated with RNA binding, hydrolysis of NTPs and RNA, and helix destabilizing properties. A cell-culture assay using an NSP2-specific mAb and polyclonal antiserum to block virus replication showed a 73 and 96 % reduction in the amount of virus produced during replication, respectively. Phage display technology was used to identify the antibody-binding region on the NSP2 protein with the motif (244)T-(Y/F)-Ø-Ø-Ø-X-K-Ø-G(252), where Ø is a hydrophilic residue and X is any amino acid. This region was mapped to the three-dimensional NSP2 crystal structure to visualize the epitope. Analysis revealed identity to a region on NSP2 that mapped to a site exposed on the surface of the protein, which could possibly interfere with a functionally important region of the protein. Antibody binding to this region could disrupt the essential roles of NSP2, such as the formation of viroplasms with NSP5 or the interaction with viral RNA, thereby indicating a possible mechanism for the observed inhibition of virus replication. Genetic analysis of the putative binding region of NSP2 revealed a high level of conservation, suggesting that the region is under strict control.
authors.affiliation: Department of Microbiology, La Trobe University, Bundoora, Victoria 3083, Australia.|Enteric Virus Group, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
authors.forename: Nicole C
authors.initials: NC
authors.lastname: Donker
authors.affiliation: Department of Biochemistry, La Trobe University, Bundoora, Victoria 3083, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Foley
authors.affiliation: Department of Biochemistry, La Trobe University, Bundoora, Victoria 3083, Australia.
authors.forename: Debra C
authors.initials: DC
authors.lastname: Tamvakis
authors.affiliation: Enteric Virus Group, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
authors.forename: Ruth
authors.initials: R
authors.lastname: Bishop
authors.affiliation: Department of Microbiology, La Trobe University, Bundoora, Victoria 3083, Australia.|Enteric Virus Group, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
authors.forename: Carl D
authors.initials: CD
authors.lastname: Kirkwood
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology* / Q000378:metabolism; D017124:Conserved Sequence; D018604:Epitope Mapping; D000939:Epitopes / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D019151:Peptide Library; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D012401:Rotavirus / Q000235:genetics / Q000276:immunology; D017422:Sequence Analysis, DNA; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism
chemical_list: D000914:Antibodies, Viral; D000939:Epitopes; D019151:Peptide Library; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D017361:Viral Nonstructural Proteins; C079234:NS35 protein, rotavirus