title: Selective incorporation of vRNP into influenza A virions determined by its specific interaction with M1 protein.
abstract: Influenza A viruses contain eight single-stranded, negative-sense RNA segments as viral genomes in the form of viral ribonucleoproteins (vRNPs). During genome replication in the nucleus, positive-sense complementary RNPs (cRNPs) are produced as replicative intermediates, which are not incorporated into progeny virions. To analyze the mechanism of selective vRNP incorporation into progeny virions, we quantified vRNPs and cRNPs in the nuclear and cytosolic fractions of infected cells, using a strand-specific qRT-PCR. Unexpectedly, we found that cRNPs were also exported to the cytoplasm. This export was chromosome region maintenance 1 (CRM1)-independent unlike that of vRNPs. Although both vRNPs and cRNPs were present in the cytosol, viral matrix (M1) protein, a key regulator for viral assembly, preferentially bound vRNPs over cRNPs. These results indicate that influenza A viruses selectively uptake cytosolic vRNPs through a specific interaction with M1 during viral assembly.
authors.affiliation: Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States; Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
authors.forename: Chutikarn
authors.initials: C
authors.lastname: Chaimayo
authors.affiliation: Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States.
authors.forename: Andrew
authors.initials: A
authors.lastname: Underwood
authors.affiliation: Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States.
authors.forename: Erin
authors.initials: E
authors.lastname: Hodges
authors.affiliation: Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States. Electronic address: toru_takimoto@urmc.rochester.edu.
authors.forename: Toru
authors.initials: T
authors.lastname: Takimoto
mesh_terms: D000072283:A549 Cells; D021581:Active Transport, Cell Nucleus; D000818:Animals; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000821:virology; D003593:Cytoplasm / Q000821:virology; D004285:Dogs; D016679:Genome, Viral / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D009980:Influenza A virus / Q000235:genetics*; D028884:Karyopherins / Q000378:metabolism; D061985:Madin Darby Canine Kidney Cells; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012261:Ribonucleoproteins / Q000378:metabolism*; D014763:Viral Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D019065:Virus Assembly / Q000235:genetics / Q000502:physiology*; D014779:Virus Replication / Q000235:genetics / Q000502:physiology*; D000097606:Exportin 1 Protein
chemical_list: D028884:Karyopherins; D012367:RNA, Viral; D018160:Receptors, Cytoplasmic and Nuclear; D012261:Ribonucleoproteins; D014763:Viral Matrix Proteins; D000097606:Exportin 1 Protein; C488936:M1 protein, Influenza A virus
keywords: Assembly; CRM1; CRNP; Influenza; M1; Nuclear export; Trafficking; VRNP