title: The structure and flexibility of conical HIV-1 capsids determined within intact virions.
abstract: HIV-1 contains a cone-shaped capsid encasing the viral genome. This capsid is thought to follow fullerene geometry-a curved hexameric lattice of the capsid protein, CA, closed by incorporating 12 CA pentamers. Current models for core structure are based on crystallography of hexameric and cross-linked pentameric CA, electron microscopy of tubular CA arrays, and simulations. Here, we report subnanometer-resolution cryo-electron tomography structures of hexameric and pentameric CA within intact HIV-1 particles. Whereas the hexamer structure is compatible with crystallography studies, the pentamer forms using different interfaces. Determining multiple structures revealed how CA flexes to form the variably curved core shell. We show that HIV-1 CA assembles both aberrant and perfect fullerene cones, supporting models in which conical cores assemble de novo after maturation.
authors.affiliation: Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.|Molecular Medicine Partnership Unit, European Molecular Biology Laboratory-Universitätsklinikum Heidelberg, Heidelberg, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Mattei
authors.affiliation: Department of Infectious Diseases, Virology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Glass
authors.affiliation: Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Wim J H
authors.initials: WJ
authors.lastname: Hagen
authors.affiliation: Molecular Medicine Partnership Unit, European Molecular Biology Laboratory-Universitätsklinikum Heidelberg, Heidelberg, Germany.|Department of Infectious Diseases, Virology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Kräusslich
authors.affiliation: Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany. john.briggs@embl.de.|Molecular Medicine Partnership Unit, European Molecular Biology Laboratory-Universitätsklinikum Heidelberg, Heidelberg, Germany.
authors.forename: John A G
authors.initials: JA
authors.lastname: Briggs
mesh_terms: D002213:Capsid / Q000737:chemistry / Q000648:ultrastructure*; D036022:Capsid Proteins / Q000737:chemistry / Q000648:ultrastructure*; D020285:Cryoelectron Microscopy; D055032:Electron Microscope Tomography; D037741:Fullerenes / Q000737:chemistry; D016679:Genome, Viral; D015497:HIV-1 / Q000737:chemistry / Q000648:ultrastructure*; D006801:Humans; D011487:Protein Conformation; D055503:Protein Multimerization; D014771:Virion / Q000737:chemistry / Q000648:ultrastructure*; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000737:chemistry / Q000648:ultrastructure*
chemical_list: D036022:Capsid Proteins; D037741:Fullerenes; D054301:gag Gene Products, Human Immunodeficiency Virus