title: Mapping the surface-exposed regions of papaya mosaic virus nanoparticles.
abstract: In general, the structure of the papaya mosaic virus (PapMV) and other members of the potexviruses is poorly understood. Production of PapMV coat proteins in a bacterial expression system and their self-assembly in vitro into nanoparticles is a very useful tool to study the structure of this virus. Using recombinant PapMV nanoparticles that are similar in shape and appearance to the plant virus, we evaluated surface-exposed regions by two different methods, immunoblot assay and chemical modification with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide or diethyl-pyrocarbonate followed by mass spectrometry. Three regions were targeted by the two techniques. The N- and C-termini were shown to be surfaced exposed as expected. However, the region 125-136 was revealed for the first time as the major surface-exposed region of the nanoparticles. The presence of linear peptides at the surface was finally confirmed using antibodies directed to those peptides. It is likely that region 125-136 plays a key role in the lifecycle of PapMV and other members of the potexvirus group.
authors.affiliation: Department of Microbiology Infectiology and Immunology, Infectious Disease Research Centre, Laval University, Quebec City, Canada.
authors.forename: Gervais
authors.initials: G
authors.lastname: Rioux
authors.forename: Nathalie
authors.initials: N
authors.lastname: Majeau
authors.forename: Denis
authors.initials: D
authors.lastname: Leclerc
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics; D029441:Carica / Q000821:virology; D004047:Diethyl Pyrocarbonate / Q000737:chemistry; D005022:Ethyldimethylaminopropyl Carbodiimide / Q000737:chemistry; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009029:Mosaic Viruses / Q000737:chemistry* / Q000235:genetics; D053758:Nanoparticles / Q000737:chemistry*; D010449:Peptide Mapping; D010455:Peptides / Q000737:chemistry* / Q000235:genetics; D010935:Plant Diseases / Q000821:virology; D011994:Recombinant Proteins / Q000737:chemistry* / Q000235:genetics
chemical_list: D036022:Capsid Proteins; D010455:Peptides; D011994:Recombinant Proteins; D004047:Diethyl Pyrocarbonate; D005022:Ethyldimethylaminopropyl Carbodiimide