title: STRUCTURAL VIROLOGY. Conformational plasticity of a native retroviral capsid revealed by x-ray crystallography.
abstract: Retroviruses depend on self-assembly of their capsid proteins (core particle) to yield infectious mature virions. Despite the essential role of the retroviral core, its high polymorphism has hindered high-resolution structural analyses. Here, we report the x-ray structure of the native capsid (CA) protein from bovine leukemia virus. CA is organized as hexamers that deviate substantially from sixfold symmetry, yet adjust to make two-dimensional pseudohexagonal arrays that mimic mature retroviral cores. Intra- and interhexameric quasi-equivalent contacts are uncovered, with flexible trimeric lateral contacts among hexamers, yet preserving very similar dimeric interfaces making the lattice. The conformation of each capsid subunit in the hexamer is therefore dictated by long-range interactions, revealing how the hexamers can also assemble into closed core particles, a relevant feature of retrovirus biology.
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Biophysics, Mataojo 2020, 11400, Montevideo, Uruguay. Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Avenida General Flores 2125, 11800, Montevideo, Uruguay.
authors.forename: G
authors.initials: G
authors.lastname: Obal
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Crystallography, Mataojo 2020, 11400, Montevideo, Uruguay.
authors.forename: F
authors.initials: F
authors.lastname: Trajtenberg
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Biophysics, Mataojo 2020, 11400, Montevideo, Uruguay.
authors.forename: F
authors.initials: F
authors.lastname: Carrión
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Biophysics, Mataojo 2020, 11400, Montevideo, Uruguay. Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Avenida General Flores 2125, 11800, Montevideo, Uruguay.
authors.forename: L
authors.initials: L
authors.lastname: Tomé
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Crystallography, Mataojo 2020, 11400, Montevideo, Uruguay.
authors.forename: N
authors.initials: N
authors.lastname: Larrieux
authors.affiliation: Institut Pasteur, Unité de Virologie Structurale, Département de Virologie and CNRS Unité Mixte de Recherche 3569, 28, Rue du Docteur Roux, 75015, Paris, France.
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Biophysics, Mataojo 2020, 11400, Montevideo, Uruguay. Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Avenida General Flores 2125, 11800, Montevideo, Uruguay. pritsch@pasteur.edu.uy alebus@pasteur.edu.uy.
authors.forename: O
authors.initials: O
authors.lastname: Pritsch
authors.affiliation: Institut Pasteur de Montevideo, Unit of Protein Crystallography, Mataojo 2020, 11400, Montevideo, Uruguay. Institut Pasteur, Department of Structural Biology and Chemistry, 25, Rue du Dr Roux, 75015, Paris, France. pritsch@pasteur.edu.uy alebus@pasteur.edu.uy.
authors.forename: A
authors.initials: A
authors.lastname: Buschiazzo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002213:Capsid / Q000737:chemistry*; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics; D002417:Cattle; D018360:Crystallography, X-Ray; D001909:Leukemia Virus, Bovine / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D055503:Protein Multimerization; D017433:Protein Structure, Secondary
chemical_list: D036022:Capsid Proteins