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Structure and assembly of immature HIV.

ABSTRACT: The major structural components of HIV are synthesized as a 55-kDa polyprotein, Gag. Particle formation is driven by the self-assembly of Gag into a curved hexameric lattice, the structure of which is poorly understood. We used cryoelectron tomography and contrast-transfer-function corrected subtomogram averaging to study the structure of the assembled immature Gag lattice to approximately 17-A resolution. Gag is arranged in the immature virus as a single, continuous, but incomplete hexameric lattice whose curvature is mediated without a requirement for pentameric defects. The resolution of the structure allows positioning of individual protein domains. High-resolution crystal structures were fitted into the reconstruction to locate protein-protein interfaces involved in Gag assembly, and to identify the structural transformations associated with virus maturation. The results of this study suggest a concept for the formation of nonsymmetrical enveloped viruses of variable sizes.

SUBMITTER: Briggs JA

PROVIDER: S-EPMC2700151 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Structure and assembly of immature HIV.

Briggs J A G JA Riches J D JD Glass B B Bartonova V V Zanetti G G Kräusslich H-G HG

Proceedings of the National Academy of Sciences of the United States of America 20090622 27

The major structural components of HIV are synthesized as a 55-kDa polyprotein, Gag. Particle formation is driven by the self-assembly of Gag into a curved hexameric lattice, the structure of which is poorly understood. We used cryoelectron tomography and contrast-transfer-function corrected subtomogram averaging to study the structure of the assembled immature Gag lattice to approximately 17-A resolution. Gag is arranged in the immature virus as a single, continuous, but incomplete hexameric la ...[more]

PMID: 19549863

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