title: The influenza virus variant A/FM/1/47-MA possesses single amino acid replacements in the hemagglutinin, controlling virulence, and in the matrix protein, controlling virulence as well as growth.
abstract: Genetic analysis of mouse-adapted influenza virus variant A/FM/1/47 (FM) MA has previously identified four genome segments, 4, 5, 7, and 8, that are statistically associated with virulence. On sequencing these genome segments, we found single amino acid replacements at amino acid 47 of the HA2 subunit of the hemagglutinin and at amino acid 139 of the matrix protein. Mutation was not detected in segments 5 and 8, obviating a role for these genes in FM-MA virulence. FM-MA replicates to higher titer than FM in MDCK cells and in mouse lung. FM X FM-MA reassortants were used to show that the M1 gene controlled replication in MDCK cells as well as in mouse lung.
authors.affiliation: Department of Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ontario, Canada.
authors.forename: C A
authors.initials: CA
authors.lastname: Smeenk
authors.forename: E G
authors.initials: EG
authors.lastname: Brown
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D004285:Dogs; D014644:Genetic Variation; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral / Q000737:chemistry / Q000235:genetics*; D009980:Influenza A virus / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D051379:Mice; D008969:Molecular Sequence Data; D013045:Species Specificity; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics*; D014774:Virulence / Q000235:genetics; D014779:Virus Replication / Q000235:genetics
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral; D014763:Viral Matrix Proteins