title: Structural and electrostatic characterization of pariacoto virus: implications for viral assembly.
abstract: We present the first all-atom model for the structure of a T = 3 virus, pariacoto virus (PaV), which is a nonenveloped, icosahedral RNA virus and a member of the Nodaviridae family. The model is an extension of the crystal structure, which reveals about 88% of the protein structure but only about 35% of the RNA structure. New modeling methods, combining coarse-grained and all-atom approaches, were required for developing the model. Evaluation of alternative models confirms our earlier observation that the polycationic N- and C-terminal tails of the capsid proteins must penetrate deeply into the core of the virus, where they stabilize the structure by neutralizing a substantial fraction of the RNA charge. This leads us to propose a model for the assembly of small icosahedral RNA viruses: nonspecific binding of the protein tails to the RNA leads to a collapse of the complex, in a fashion reminiscent of DNA condensation. The globular protein domains are excluded from the condensed phase but are tethered to it, so they accumulate in a shell around the condensed phase, where their concentration is high enough to trigger oligomerization and formation of the mature virus.
authors.affiliation: School of Biology, Georgia Institute of Technology, Atlanta, GA 30332-0230, USA.
authors.forename: Batsal
authors.initials: B
authors.lastname: Devkota
authors.forename: Anton S
authors.initials: AS
authors.lastname: Petrov
authors.forename: Sébastien
authors.initials: S
authors.lastname: Lemieux
authors.forename: Mustafa Burak
authors.initials: MB
authors.lastname: Boz
authors.forename: Liang
authors.initials: L
authors.lastname: Tang
authors.forename: Anette
authors.initials: A
authors.lastname: Schneemann
authors.forename: John E
authors.initials: JE
authors.lastname: Johnson
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Harvey
mesh_terms: D016679:Genome, Viral / Q000235:genetics; D008958:Models, Molecular; D030381:Nodaviridae / Q000737:chemistry* / Q000235:genetics; D012367:RNA, Viral / Q000737:chemistry; D055672:Static Electricity; D019065:Virus Assembly
chemical_list: D012367:RNA, Viral