tetano
Editor, Senior Moderator
J Virol. 2014 Dec 24. pii: JVI.02953-14. [Epub ahead of print]
[h=1]Ribonuclease L Targets Distinct Sites in Influenza A Virus RNAs.[/h] Cooper DA[SUP]1[/SUP], Banerjee S[SUP]2[/SUP], Chakrabarti A[SUP]2[/SUP], Garc?a-Sastre A[SUP]3[/SUP], Hesselberth JR[SUP]4[/SUP], Silverman RH[SUP]2[/SUP], Barton DJ[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A virus (IAV) infections are influenced by type 1 interferon-mediated antiviral defenses and by viral countermeasures to these defenses. When IAV NS1 protein is disabled, ribonuclease L (RNase L) restricts virus replication; however, the RNAs targeted for cleavage by RNase L under these conditions have not been defined. In this study, we used deep sequencing methods to identify RNase L cleavage sites within host and viral RNAs from IAV PR8ΔNS1-infected A549 cells. ShRNA knockdown of RNase L allowed us to distinguish between RNase L-dependent and RNase L-independent cleavage sites. RNase L-dependent cleavage sites were evident at discrete locations in IAV RNA segments [both (+) and (-) strands]. Cleavage in PB2, PB1 and PA genomic RNAs suggests that viral RNPs are susceptible to cleavage by RNase L. Prominent amounts of cleavage mapped to specific regions within IAV RNAs, including some areas of increased synonymous site conservation. Among cellular RNAs, RNase L-dependent cleavage was most frequent at precise locations in ribosomal RNAs. Our data show that RNase L targets specific sites in both host and viral RNAs to restrict influenza virus replication when NS1 protein is disabled.
[h=4]IMPORTANCE:[/h] Ribonuclease L (RNase L) is a critical component of interferon-regulated and dsRNA-activated antiviral host responses. We sought to determine how RNase L exerts its antiviral activity during influenza virus infection. We enhanced the antiviral activity of RNase L by disabling a viral protein, NS1, that inhibits the activation of RNase L. Then, using deep sequencing methods, we identified the host and viral RNAs targeted by RNase L. We found that RNase L cleaved viral RNAs and ribosomal RNAs at very precise locations. The direct cleavage of IAV RNAs by RNase L highlights an intimate battle between viral RNAs and an antiviral endonuclease.
Copyright ? 2014, American Society for Microbiology. All Rights Reserved.
PMID: 25540362 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25540362
[h=1]Ribonuclease L Targets Distinct Sites in Influenza A Virus RNAs.[/h] Cooper DA[SUP]1[/SUP], Banerjee S[SUP]2[/SUP], Chakrabarti A[SUP]2[/SUP], Garc?a-Sastre A[SUP]3[/SUP], Hesselberth JR[SUP]4[/SUP], Silverman RH[SUP]2[/SUP], Barton DJ[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A virus (IAV) infections are influenced by type 1 interferon-mediated antiviral defenses and by viral countermeasures to these defenses. When IAV NS1 protein is disabled, ribonuclease L (RNase L) restricts virus replication; however, the RNAs targeted for cleavage by RNase L under these conditions have not been defined. In this study, we used deep sequencing methods to identify RNase L cleavage sites within host and viral RNAs from IAV PR8ΔNS1-infected A549 cells. ShRNA knockdown of RNase L allowed us to distinguish between RNase L-dependent and RNase L-independent cleavage sites. RNase L-dependent cleavage sites were evident at discrete locations in IAV RNA segments [both (+) and (-) strands]. Cleavage in PB2, PB1 and PA genomic RNAs suggests that viral RNPs are susceptible to cleavage by RNase L. Prominent amounts of cleavage mapped to specific regions within IAV RNAs, including some areas of increased synonymous site conservation. Among cellular RNAs, RNase L-dependent cleavage was most frequent at precise locations in ribosomal RNAs. Our data show that RNase L targets specific sites in both host and viral RNAs to restrict influenza virus replication when NS1 protein is disabled.
[h=4]IMPORTANCE:[/h] Ribonuclease L (RNase L) is a critical component of interferon-regulated and dsRNA-activated antiviral host responses. We sought to determine how RNase L exerts its antiviral activity during influenza virus infection. We enhanced the antiviral activity of RNase L by disabling a viral protein, NS1, that inhibits the activation of RNase L. Then, using deep sequencing methods, we identified the host and viral RNAs targeted by RNase L. We found that RNase L cleaved viral RNAs and ribosomal RNAs at very precise locations. The direct cleavage of IAV RNAs by RNase L highlights an intimate battle between viral RNAs and an antiviral endonuclease.
Copyright ? 2014, American Society for Microbiology. All Rights Reserved.
PMID: 25540362 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25540362