tetano
Editor, Senior Moderator
J Interferon Cytokine Res. 2019 Apr 2. doi: 10.1089/jir.2018.0157. [Epub ahead of print]
[h=1]Anti-Influenza A Virus Activities of Type I/III Interferons-Induced Mx1 GTPases from Different Mammalian Species.[/h] Dam Van P[SUP]1,[/SUP][SUP]2[/SUP], Desmecht D[SUP]2[/SUP], Garigliany MM[SUP]2[/SUP], Bui Tran Anh D[SUP]3[/SUP], Van Laere AS[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Type I/III interferons provide powerful and universal innate intracellular defense mechanisms against viruses. Among the antiviral effectors induced, Mx proteins of some species appear as key components of defense against influenza A viruses. It is expected that such an antiviral protein must display a platform dedicated to the recognition of said viruses. In an attempt to identify such platform in human MxA, an evolution-guided approach capitalizing on the antagonistic arms race between MxA and its viral targets and the genomic signature it left on primate genomes revealed that the surface-exposed so-called "loop L4", which protrudes from the compact structure of the MxA stalk, is a hotspot of recurrent positive selection. Since MxA is archetypic of Mx1 proteins in general, we reasoned that the L4 loop also functions as a recognition platform for influenza viruses in the Mx1 proteins of other species that had been exposed to the virus for ever. In this study, the anti-influenza activity of 5 distinct mammalian Mx1 proteins was measured by comparing the number of viral nucleoprotein-positive cells 7 h after infection in a sample of 100,000 cells expected to contain both Mx1-positive and Mx1-negative cell subpopulations. The systematic depletion (P < 0.001) of virus nucleoprotein-positive cells among equine, bubaline, porcine, and bovine Mx1-expressing cell populations compared with Mx-negative cells suggests a strong anti-influenza A activity. Looking for common anti-influenza signature elements in the sequence of these Mx proteins, we found that an aromatic residue at positions 561 or 562 in the L4 loop seems critical for the anti-influenza function and/or specificity of mammalian Mx1.
[h=4]KEYWORDS:[/h] Mx1; buffalo; cow; dog; horse; influenza; pig; type I/III interferons
PMID: 30939061 DOI: 10.1089/jir.2018.0157
[h=1]Anti-Influenza A Virus Activities of Type I/III Interferons-Induced Mx1 GTPases from Different Mammalian Species.[/h] Dam Van P[SUP]1,[/SUP][SUP]2[/SUP], Desmecht D[SUP]2[/SUP], Garigliany MM[SUP]2[/SUP], Bui Tran Anh D[SUP]3[/SUP], Van Laere AS[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Type I/III interferons provide powerful and universal innate intracellular defense mechanisms against viruses. Among the antiviral effectors induced, Mx proteins of some species appear as key components of defense against influenza A viruses. It is expected that such an antiviral protein must display a platform dedicated to the recognition of said viruses. In an attempt to identify such platform in human MxA, an evolution-guided approach capitalizing on the antagonistic arms race between MxA and its viral targets and the genomic signature it left on primate genomes revealed that the surface-exposed so-called "loop L4", which protrudes from the compact structure of the MxA stalk, is a hotspot of recurrent positive selection. Since MxA is archetypic of Mx1 proteins in general, we reasoned that the L4 loop also functions as a recognition platform for influenza viruses in the Mx1 proteins of other species that had been exposed to the virus for ever. In this study, the anti-influenza activity of 5 distinct mammalian Mx1 proteins was measured by comparing the number of viral nucleoprotein-positive cells 7 h after infection in a sample of 100,000 cells expected to contain both Mx1-positive and Mx1-negative cell subpopulations. The systematic depletion (P < 0.001) of virus nucleoprotein-positive cells among equine, bubaline, porcine, and bovine Mx1-expressing cell populations compared with Mx-negative cells suggests a strong anti-influenza A activity. Looking for common anti-influenza signature elements in the sequence of these Mx proteins, we found that an aromatic residue at positions 561 or 562 in the L4 loop seems critical for the anti-influenza function and/or specificity of mammalian Mx1.
[h=4]KEYWORDS:[/h] Mx1; buffalo; cow; dog; horse; influenza; pig; type I/III interferons
PMID: 30939061 DOI: 10.1089/jir.2018.0157