tetano
Editor, Senior Moderator
Antimicrob Agents Chemother. 2015 Apr 27. pii: AAC.00306-15. [Epub ahead of print]
[h=1]Cross Protection of Influenza A Virus Infection by A DNA Aptamer targeting The PA Endonuclease Domain.[/h] Yuan S[SUP]1[/SUP], Zhang N[SUP]1[/SUP], Singh K[SUP]2[/SUP], Shuai H[SUP]1[/SUP], Chu H[SUP]1[/SUP], Zhou J[SUP]1[/SUP], Chow BK[SUP]2[/SUP], Zheng BJ[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Amino acid residues in the N-terminal of the PA subunit (PA[SUB]N[/SUB]) of the Influenza A polymerase play critical roles in endonuclease activity, protein stability and vRNA promoter binding. In addition, PA[SUB]N[/SUB] is highly conserved among different subtypes of the influenza virus, which suggests PA[SUB]N[/SUB] to be a desired target for the development of anti-influenza agents. We selected DNA aptamers targeting the intact PA protein or the PA[SUB]N[/SUB] domain of an H5N1 virus strain using Systematic evolution of ligands by exponential enrichment (SELEX). Binding affinities of selected aptamers were measured, followed by evaluation of in vitro endonuclease inhibitory activity. Next, antiviral effects of enriched aptamers against influenza A virus infections were examined. A total of three aptamers targeting PA and six aptamers targeting PA[SUB]N[/SUB] were selected. Our data demonstrated that all three PA-selected aptamers neither inhibited endonuclease activity nor exhibited antiviral efficacy, whereas four of the six PA[SUB]N[/SUB]-selected aptamers inhibited both endonuclease activity and H5N1 virus infection. Among the four effective aptamers, one exhibited cross-protection against infections of H1N1, H5N1, H7N7 and H7N9 influenza viruses with 50% inhibitory concentration (IC[SUB]50[/SUB]) around 10 nM. Notably, this aptamer was identified at the 5th round but disappeared after the 10th round of the selection, suggesting that the identification and evaluation of aptamers at early rounds of the selection may be highly helpful for screening effective aptamers. Overall, our study provides novel insights for screening and developing effective aptamers as anti-influenza drugs.
Copyright ? 2015, American Society for Microbiology. All Rights Reserved.
PMID: 25918143 [PubMed - as supplied by publisher]
[h=1]Cross Protection of Influenza A Virus Infection by A DNA Aptamer targeting The PA Endonuclease Domain.[/h] Yuan S[SUP]1[/SUP], Zhang N[SUP]1[/SUP], Singh K[SUP]2[/SUP], Shuai H[SUP]1[/SUP], Chu H[SUP]1[/SUP], Zhou J[SUP]1[/SUP], Chow BK[SUP]2[/SUP], Zheng BJ[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Amino acid residues in the N-terminal of the PA subunit (PA[SUB]N[/SUB]) of the Influenza A polymerase play critical roles in endonuclease activity, protein stability and vRNA promoter binding. In addition, PA[SUB]N[/SUB] is highly conserved among different subtypes of the influenza virus, which suggests PA[SUB]N[/SUB] to be a desired target for the development of anti-influenza agents. We selected DNA aptamers targeting the intact PA protein or the PA[SUB]N[/SUB] domain of an H5N1 virus strain using Systematic evolution of ligands by exponential enrichment (SELEX). Binding affinities of selected aptamers were measured, followed by evaluation of in vitro endonuclease inhibitory activity. Next, antiviral effects of enriched aptamers against influenza A virus infections were examined. A total of three aptamers targeting PA and six aptamers targeting PA[SUB]N[/SUB] were selected. Our data demonstrated that all three PA-selected aptamers neither inhibited endonuclease activity nor exhibited antiviral efficacy, whereas four of the six PA[SUB]N[/SUB]-selected aptamers inhibited both endonuclease activity and H5N1 virus infection. Among the four effective aptamers, one exhibited cross-protection against infections of H1N1, H5N1, H7N7 and H7N9 influenza viruses with 50% inhibitory concentration (IC[SUB]50[/SUB]) around 10 nM. Notably, this aptamer was identified at the 5th round but disappeared after the 10th round of the selection, suggesting that the identification and evaluation of aptamers at early rounds of the selection may be highly helpful for screening effective aptamers. Overall, our study provides novel insights for screening and developing effective aptamers as anti-influenza drugs.
Copyright ? 2015, American Society for Microbiology. All Rights Reserved.
PMID: 25918143 [PubMed - as supplied by publisher]