Cryo-electron Tomography of Porcine Reproductive and Respiratory Syndrome Virus: Organization of the Nucleocapsid
Porcine reproductive and respiratory virus (PRRSV) is an enveloped positive-sense RNA virus of the familyArteriviridae 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.
Journal of General Virology
DOI of Published Version
Spilman, Michael S.; Welbon, Craig; Nelson, Eric A.; and Dokland, Terje, "Cryo-electron Tomography of Porcine Reproductive and Respiratory Syndrome Virus: Organization of the Nucleocapsid" (2009). Veterinary and Biomedical Sciences Faculty Publications. 39.