title: Influenza NA and PB1 Gene Segments Interact during the Formation of Viral Progeny: Localization of the Binding Region within the PB1 Gene.
abstract: The influenza A virus genome comprises eight negative-sense viral RNAs (vRNAs) that form individual ribonucleoprotein (RNP) complexes. In order to incorporate a complete set of each of these vRNAs, the virus uses a selective packaging mechanism that facilitates co-packaging of specific gene segments but whose molecular basis is still not fully understood. Recently, we used a competitive transfection model where plasmids encoding the A/Puerto Rico/8/34 (PR8) and A/Udorn/307/72 (Udorn) PB1 gene segments were competed to show that the Udorn PB1 gene segment is preferentially co-packaged into progeny virions with the Udorn NA gene segment. Here we created chimeric PB1 genes combining both Udorn and PR8 PB1 sequences to further define the location within the Udorn PB1 gene that drives co-segregation of these genes and show that nucleotides 1776-2070 of the PB1 gene are crucial for preferential selection. In vitro assays examining specific interactions between Udorn NA vRNA and purified vRNAs transcribed from chimeric PB1 genes also supported the importance of this region in the PB1-NA interaction. Hence, this work identifies an association between viral genes that are co-selected during packaging. It also reveals a region potentially important in the RNP-RNP interactions within the supramolecular complex that is predicted to form prior to budding to allow one of each segment to be packaged in the viral progeny. Our study lays the foundation to understand the co-selection of specific genes, which may be critical to the emergence of new viruses with pandemic potential.
authors.affiliation: Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute of Infection and Immunity, Parkville 3010, Victoria, Australia. bg@unimelb.edu.au.
authors.forename: Brad
authors.initials: B
authors.lastname: Gilbertson
authors.affiliation: Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute of Infection and Immunity, Parkville 3010, Victoria, Australia. tianchi.zheng@gmail.com.
authors.forename: Tian
authors.initials: T
authors.lastname: Zheng
authors.affiliation: Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 15 rue René Descartes, Strasbourg 67084, France. m.gerber@ibmc-cnrs.unistra.fr.
authors.forename: Marie
authors.initials: M
authors.lastname: Gerber
authors.affiliation: Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 15 rue René Descartes, Strasbourg 67084, France. A.schweigert@ibmc-cnrs.unistra.fr.
authors.forename: Anne
authors.initials: A
authors.lastname: Printz-Schweigert
authors.affiliation: Seqirus, 63 Poplar Rd, Parkville 3052, Victoria, Australia. Chi.Ong@seqirus.com.
authors.forename: Chi
authors.initials: C
authors.lastname: Ong
authors.affiliation: Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 15 rue René Descartes, Strasbourg 67084, France. r.marquet@ibmc-cnrs.unistra.fr.
authors.forename: Roland
authors.initials: R
authors.lastname: Marquet
authors.affiliation: Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, IBMC, 15 rue René Descartes, Strasbourg 67084, France. c.isel@ibmc-cnrs.unistra.fr.|Unité de Génétique Moléculaire des Virus à ARN, Département de virologie, Institut Pasteur, Paris 75005, France. c.isel@ibmc-cnrs.unistra.fr.
authors.forename: Catherine
authors.initials: C
authors.lastname: Isel
authors.affiliation: Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute of Infection and Immunity, Parkville 3010, Victoria, Australia. Steve.Rockman@seqirus.com.|Seqirus, 63 Poplar Rd, Parkville 3052, Victoria, Australia. Steve.Rockman@seqirus.com.
authors.forename: Steven
authors.initials: S
authors.lastname: Rockman
authors.affiliation: Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute of Infection and Immunity, Parkville 3010, Victoria, Australia. lorena@unimelb.edu.au.
authors.forename: Lorena
authors.initials: L
authors.lastname: Brown
mesh_terms: D000818:Animals; D002460:Cell Line; D004252:DNA Mutational Analysis; D006801:Humans; D009980:Influenza A virus / Q000502:physiology*; D009439:Neuraminidase / Q000235:genetics*; D010957:Plasmids; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism*; D059386:Reverse Genetics; D014764:Viral Proteins / Q000235:genetics*; D019065:Virus Assembly
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1; C487630:NA protein, influenza A virus; D009439:Neuraminidase
keywords: RNA-RNA interaction; competitive transfection; gene segments; influenza virus; packaging; reassortment; viral polymerase