tetano
Editor, Senior Moderator
J Virol. 2013 Dec 11. [Epub ahead of print]
Specific nucleoprotein residues affect influenza virus morphology.
Bialas KM, Bussey KA, Stone RL, Takimoto T.
Author information
Abstract
Influenza virus strains are often pleiomorphic, a characteristic that is largely attributed to specific residues in the matrix protein 1 (M1). Although the mechanism by which M1 controls virion morphology has not yet been defined, it is suggested that the M1 interaction with other viral proteins plays an important role. In this study, we rescued recombinant virus WSN-AichiM1 containing the spherical A/WSN/33 (WSN) backbone and the M1 protein from A/Aichi/2/68 (Aichi). Aichi M1 differs from WSN M1 by 7 amino acids, but includes those identified to be responsible for filamentous virion formation. Interestingly, Aichi produced spherical virions, while WSN-AichiM1 exhibited long filamentous morphology as detected by immunofluorescence and electron microscopy. Additional incorporation of Aichi NP, but not HA, NA, or M2 genes to WSN-AichiM1 abrogated filamentous virion formation, suggesting that specific M1-NP interactions affect virion morphology. Further characterization of viruses containing WSN/Aichi chimeric NPs identified residues 214, 217 and 253 of Aichi NP as necessary and sufficient for the formation of spherical virions. NP residues 214 and 217 localize at the minor groove between the two opposite-polarity NP helical strands of viral ribonucleocapsids, and residue 253 also localizes near the surface of the groove. These findings indicate that NP plays a critical role in influenza morphology, possibly through its interaction with the M1 layer during virus budding.
PMID:
24335312
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24335312
Specific nucleoprotein residues affect influenza virus morphology.
Bialas KM, Bussey KA, Stone RL, Takimoto T.
Author information
Abstract
Influenza virus strains are often pleiomorphic, a characteristic that is largely attributed to specific residues in the matrix protein 1 (M1). Although the mechanism by which M1 controls virion morphology has not yet been defined, it is suggested that the M1 interaction with other viral proteins plays an important role. In this study, we rescued recombinant virus WSN-AichiM1 containing the spherical A/WSN/33 (WSN) backbone and the M1 protein from A/Aichi/2/68 (Aichi). Aichi M1 differs from WSN M1 by 7 amino acids, but includes those identified to be responsible for filamentous virion formation. Interestingly, Aichi produced spherical virions, while WSN-AichiM1 exhibited long filamentous morphology as detected by immunofluorescence and electron microscopy. Additional incorporation of Aichi NP, but not HA, NA, or M2 genes to WSN-AichiM1 abrogated filamentous virion formation, suggesting that specific M1-NP interactions affect virion morphology. Further characterization of viruses containing WSN/Aichi chimeric NPs identified residues 214, 217 and 253 of Aichi NP as necessary and sufficient for the formation of spherical virions. NP residues 214 and 217 localize at the minor groove between the two opposite-polarity NP helical strands of viral ribonucleocapsids, and residue 253 also localizes near the surface of the groove. These findings indicate that NP plays a critical role in influenza morphology, possibly through its interaction with the M1 layer during virus budding.
PMID:
24335312
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24335312