tetano
Editor, Senior Moderator
J Virol. 2017 Oct 18. pii: JVI.00858-17. doi: 10.1128/JVI.00858-17. [Epub ahead of print]
[h=1]Mutations in the Influenza A virus M1 protein enhance virus budding to complement lethal mutations in the M2 cytoplasmic tail.[/h] Liu H[SUP]1[/SUP], Grantham ML[SUP]1[/SUP], Pekosz A[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] The influenza A virus M1 and M2 proteins play important roles in virus assembly and in the morphology of virus particles. Mutations in the distal cytoplasmic tail region of M2, and in particular a tyrosine to alanine substitution at residue 76 (Y76A) was essential for infectious virus production and filament formation while having limited effects on total virus particle budding. Using a novel selection method, mutations at seven different M1 amino acids (residue 73, 94, 135, 136, or 138 or a double mutation 93/244) that are not found in circulating influenza virus strains or been previously identified to play a role in influenza A virus assembly were found to complement the lethal M2Y76A mutation. These M1 suppressor mutations restored infectious virus production in the presence of M2Y76A and mediated increased budding and filament formation even in the absence of M2. However, the efficiency of infectious virus replication was still dependent on the presence of the distal region of the M2 cytoplasmic tail. The data suggest influenza A virus budding and genome incorporation can occur independently, and provide further support for complementary roles of the M1 and M2 proteins in virus assembly.Importance Influenza virus particle assembly involves the careful coordination of various viral and host factors to optimally produce infectious virus particles. We have previously identified a mutation at position 76 of the influenza A virus M2 protein that drastically reduces infectious virus production and filament formation with minimal effects on virus budding. In this manuscript, we identified suppressor mutations in the M1 protein which complement this lethal M2 mutation by increasing the efficiency in which virus particles bud from infected cells and restoring filament formation at the infected cell surface. M2 distal cytoplasmic domain sequences were still required for optimal infectivity. This indicates that M1 and M2 can functionally replace each other in some, but not all aspects of virus particle assembly.
Copyright ? 2017 American Society for Microbiology.
PMID: 29046451 DOI: 10.1128/JVI.00858-17
[h=1]Mutations in the Influenza A virus M1 protein enhance virus budding to complement lethal mutations in the M2 cytoplasmic tail.[/h] Liu H[SUP]1[/SUP], Grantham ML[SUP]1[/SUP], Pekosz A[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] The influenza A virus M1 and M2 proteins play important roles in virus assembly and in the morphology of virus particles. Mutations in the distal cytoplasmic tail region of M2, and in particular a tyrosine to alanine substitution at residue 76 (Y76A) was essential for infectious virus production and filament formation while having limited effects on total virus particle budding. Using a novel selection method, mutations at seven different M1 amino acids (residue 73, 94, 135, 136, or 138 or a double mutation 93/244) that are not found in circulating influenza virus strains or been previously identified to play a role in influenza A virus assembly were found to complement the lethal M2Y76A mutation. These M1 suppressor mutations restored infectious virus production in the presence of M2Y76A and mediated increased budding and filament formation even in the absence of M2. However, the efficiency of infectious virus replication was still dependent on the presence of the distal region of the M2 cytoplasmic tail. The data suggest influenza A virus budding and genome incorporation can occur independently, and provide further support for complementary roles of the M1 and M2 proteins in virus assembly.Importance Influenza virus particle assembly involves the careful coordination of various viral and host factors to optimally produce infectious virus particles. We have previously identified a mutation at position 76 of the influenza A virus M2 protein that drastically reduces infectious virus production and filament formation with minimal effects on virus budding. In this manuscript, we identified suppressor mutations in the M1 protein which complement this lethal M2 mutation by increasing the efficiency in which virus particles bud from infected cells and restoring filament formation at the infected cell surface. M2 distal cytoplasmic domain sequences were still required for optimal infectivity. This indicates that M1 and M2 can functionally replace each other in some, but not all aspects of virus particle assembly.
Copyright ? 2017 American Society for Microbiology.
PMID: 29046451 DOI: 10.1128/JVI.00858-17