A Mutation on Influenza C Virus M1 Protein Affects Virion Morphology by Altering the Membrane Affinity of the Protein
Autor: | Emi Takashita, Seiji Hongo, Yasushi Muraki, Kanetsu Sugawara, Toshio Murata, Yoko Matsuzaki |
---|---|
Rok vydání: | 2007 |
Předmět: |
Threonine
Influenzavirus C viruses Molecular Sequence Data Immunology M1 protein Orthomyxoviridae medicine.disease_cause Recombinant virus Microbiology Virus Viral Matrix Proteins Virology Influenza A virus medicine Humans Amino Acid Sequence Cloning Molecular Alanine Viral matrix protein biology Cell Membrane Virion biology.organism_classification Molecular biology Genome Replication and Regulation of Viral Gene Expression Amino Acid Substitution Insect Science Mutation biology.protein RNA Viral Influenza C Virus |
Zdroj: | Journal of Virology. 81:8766-8773 |
ISSN: | 1098-5514 0022-538X |
Popis: | Reverse genetics has been documented for influenza A, B, and Thogoto viruses belonging to the family Orthomyxoviridae . We report here the reverse genetics of influenza C virus, another member of this family. The seven viral RNA (vRNA) segments of C/Ann Arbor/1/50 were expressed in 293T cells from cloned cDNAs, together with nine influenza C virus proteins. At 48 h posttransfection, the infectious titer of the culture supernatant was determined to be 2.51 × 10 3 50% egg infectious doses/ml, which is lower than the number of influenza C virus-like particles (VLPs) (10 6 /ml) generated using the same system. By generating influenza C VLPs containing a given vRNA segment, we showed that each of the vRNA segments was similarly synthesized in the plasmid-transfected cells but that some segments were less efficiently incorporated into the VLPs. This finding leads us to speculate that the differences in incorporation efficiency into VLPs between segments might be a reason for the inefficient production of infectious viruses. Second, we generated a mutant recombinant virus, rMG96A, which possesses an Ala→Thr mutation at residue 24 of the M1 protein, a substitution demonstrated to be involved in the morphology (filamentous or spherical) of the influenza C VLPs. As expected, rMG96A exhibited a spherical morphology, whereas recombinant wild-type of C/Ann Arbor/1/50, rWT, exhibited a mainly filamentous morphology. Membrane flotation analysis of the cells infected with rWT or rMG96A revealed a difference in the ratio of membrane-associated M1 proteins, suggesting that the affinity of M1 protein to the cell membrane is a determinant for virion morphology. |
Databáze: | OpenAIRE |
Externí odkaz: |