[Source: Science, full page: (LINK). Abstract, edited.]
Published Online November 22 2012 / Science 21 December 2012: Vol. 338 no. 6114 pp. 1631-1634 / DOI: 10.1126/science.1227270
Organization of the Influenza Virus Replication Machinery
Arne Moeller1,*, Robert N. Kirchdoerfer2,*, Clinton S. Potter1, Bridget Carragher1,†, Ian A. Wilson2,3,†
Author Affiliations: 1National Resource for Automated Molecular Microscopy, Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA. 2Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA. 3The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
* These authors contributed equally to this work.
Influenza virus ribonucleoprotein complexes (RNPs) are central to the viral life cycle and in adaptation to new host species. RNPs are composed of the viral genome, viral polymerase, and many copies of the viral nucleoprotein. In vitro cell expression of all RNP protein components with four of the eight influenza virus gene segments enabled structural determination of native influenza virus RNPs by means of cryogenic electron microscopy (cryo-EM). The cryo-EM structure reveals the architecture and organization of the native RNP, defining the attributes of its largely helical structure and how polymerase interacts with nucleoprotein and the viral genome. Observations of branched-RNP structures in negative-stain electron microscopy and their putative identification as replication intermediates suggest a mechanism for viral replication by a second polymerase on the RNP template.
Received for publication 11 July 2012. - Accepted for publication 26 October 2012.