title: The influenza A virus spliced messenger RNA M mRNA3 is not required for viral replication in tissue culture.
abstract: Influenza A virus genome RNA segment 7 encodes three known mRNAs, two of which, M2 mRNA and M mRNA3, are derived by alternative splicing of the primary collinear mRNA transcript using alternative 5' splice sites. The function of M mRNA3 is currently unknown, therefore we attempted to determine whether it is essential for virus replication. Recombinant viruses unable to produce M mRNA3 and/or M2 mRNA were created by mutating the shared 3' splice site. Growth of the mutant viruses in M2-expressing MDCK cells was not significantly affected by the lack of M mRNA3. During the course of a wild-type virus infection, levels of M mRNA3 began to decrease while those of M2 mRNA increased, which may indicate a potential mechanism of alternative splicing control. These data suggest that neither M mRNA3 nor any potential protein product are essential for influenza virus replication in tissue culture.
authors.affiliation: Howard Hughes Medical Institute and Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208-3500, USA.
authors.forename: David
authors.initials: D
authors.lastname: Jackson
authors.affiliation: Howard Hughes Medical Institute and Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208-3500, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Lamb
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D002460:Cell Line; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D009154:Mutation; D022821:RNA Splice Sites; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism; D014763:Viral Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication; D000086082:Viroporin Proteins
chemical_list: D022821:RNA Splice Sites; D012333:RNA, Messenger; D012367:RNA, Viral; D014763:Viral Matrix Proteins; C031540:M-protein, influenza virus; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins