title: Organization of the influenza virus replication machinery.
abstract: 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.
authors.affiliation: National Resource for Automated Molecular Microscopy, Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Arne
authors.initials: A
authors.lastname: Moeller
authors.forename: Robert N
authors.initials: RN
authors.lastname: Kirchdoerfer
authors.forename: Clinton S
authors.initials: CS
authors.lastname: Potter
authors.forename: Bridget
authors.initials: B
authors.lastname: Carragher
authors.forename: Ian A
authors.initials: IA
authors.lastname: Wilson
mesh_terms: D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D016679:Genome, Viral; D007091:Image Processing, Computer-Assisted; D053118:Influenza A Virus, H1N1 Subtype / Q000737:chemistry* / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D019590:Nucleocapsid Proteins; D011487:Protein Conformation; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D012367:RNA, Viral / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D012261:Ribonucleoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D014158:Transcription, Genetic; D014758:Viral Core Proteins / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D014764:Viral Proteins / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D014779:Virus Replication
chemical_list: C048842:NP protein, Influenza A virus; D019590:Nucleocapsid Proteins; D021122:Protein Subunits; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; D014758:Viral Core Proteins; D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1; D012324:RNA-Dependent RNA Polymerase