[Source: Science, full page: (LINK). Abstract, edited.]
Published Online November 22 2012 / Science 21 December 2012: Vol. 338 no. 6114 pp. 1634-1637 / DOI: 10.1126/science.1228172
The Structure of Native Influenza Virion Ribonucleoproteins
Rocío Arranz1, Rocío Coloma2,3, Francisco Javier Chichón1, José Javier Conesa1, José L. Carrascosa1,4, José M. Valpuesta1, Juan Ortín2,3,*, Jaime Martín-Benito1,*
Author Affiliations: 1Department of Macromolecular Structure, Centro Nacional de Biotecnología [Consejo Superior de Investigaciones Cienfícas (CSIC)], Madrid, Spain. 2Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología (CSIC), Madrid, Spain. 3Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Respiratorias (Instituto National de Salud Carlos III), Madrid, Spain. 4Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia), Madrid, Spain.
The influenza viruses cause annual epidemics of respiratory disease and occasional pandemics, which constitute a major public-health issue. The segmented negative-stranded RNAs are associated with the polymerase complex and nucleoprotein (NP), forming ribonucleoproteins (RNPs), which are responsible for virus transcription and replication. We describe the structure of native RNPs derived from virions. They show a double-helical conformation in which two NP strands of opposite polarity are associated with each other along the helix. Both strands are connected by a short loop at one end of the particle and interact with the polymerase complex at the other end. This structure will be relevant for unraveling the mechanisms of nuclear import of parental virus RNPs, their transcription and replication, and the encapsidation of progeny RNPs into virions.
Received for publication 30 July 2012. - Accepted for publication 31 October 2012.