Cryo-electron tomography of porcine reproductive and respiratory syndrome virus: Organization of the nucleocapsid

Academic Article


  • Porcine reproductive and respiratory virus (PRRSV) is an enveloped positive-sense RNA virus of the family Arteriviridae that causes severe and persistent disease in pigs worldwide. The PRRSV virion consists of a lipid envelope that contains several envelope proteins surrounding a nucleocapsid core that encapsidates the RNA genome. To provide a better understanding of the structure and assembly of PRRSV, we have carried out cryo-electron microscopy and tomographic reconstruction of virions grown in MARC-145 cells. The virions are pleomorphic, round to egg-shaped particles with an average diameter of 58 nm. The particles display a smooth outer surface with only a few protruding features, presumably corresponding to the envelope protein complexes. The virions contain a double-layered, hollow core with an average diameter of 39 nm, which is separated from the envelope by a 2-3 nm gap. Analysis of the three-dimensional structure suggests that the core is composed of a double-layered chain of nucleocapsid proteins bundled into a hollow ball. © 2009 SGM.
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Spilman MS; Welbon C; Nelson E; Dokland T
  • Start Page

  • 527
  • End Page

  • 535
  • Volume

  • 90
  • Issue

  • 3