title: Encapsidation of DNA, a protein and a fluorophore into virus-like particles by the capsid protein of cucumber mosaic virus.
abstract: An important property of some spherical plant viruses is their ability to reassemble in vitro from native capsid protein (CP) and RNA into infectious virus-like particles (VLPs). Virions of cucumber mosaic virus (CMV) are stabilized by protein-RNA interactions and the nucleic acid is essential for assembly. This study demonstrated that VLPs will form in the presence of both ssDNA and dsDNA oligonucleotides, and with a lower size limit of 20 nt. Based on urea disruption assays, assembled VLPs from CMV CP and RNA (termed ReCMV) exhibited a level of stability similar to that of virions purified from plants, whilst VLPs from CMV CP and a 20mer exhibited comparable or greater stability. Fluorescent labelling of VLPs was achieved by the encapsidation of an Alexa Fluor 488-labelled 45mer oligonucleotide (ReCMV-Alexa488-45) and confirmed by transmission electron and confocal microscopy. Using ssDNA as a nucleating factor, encapsidation of fluorescently labelled streptavidin (53 kDa) conjugated to a biotinylated oligonucleotide was observed. The biological activity and stability of ReCMV and ReCMV-Alexa488-45 was confirmed in infectivity assays and insect vector feeding assays. This work demonstrates the utility of CMV CP as a protein cage for use in the growing repertoire of nanotechnological applications.
authors.affiliation: Department of Plant Pathology and Plant-Microbe Biology, 334 Plant Science, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Plant Pathology and Plant-Microbe Biology, 334 Plant Science, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: Thompson
authors.affiliation: Department of Plant Pathology and Plant-Microbe Biology, 334 Plant Science, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Keith L
authors.initials: KL
authors.lastname: Perry
mesh_terms: D000818:Animals; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism*; D017799:Cucumovirus / Q000235:genetics*; D004247:DNA / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism*; D007313:Insecta; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D055503:Protein Multimerization; D022701:Virosomes / Q000235:genetics / Q000378:metabolism*
chemical_list: D036022:Capsid Proteins; D004277:DNA, Single-Stranded; D005456:Fluorescent Dyes; D022701:Virosomes; D004247:DNA