Single-stranded DNA aptamer that specifically binds to the influenza virus NS1 protein suppresses interferon antagonism.
Non-structural protein 1 (NS1) of the influenza A virus (IAV) inhibits the host's innate immune response by suppressing the induction of interferons (IFNs). Therefore, blocking NS1 activity can be a potential strategy in the development of antiviral agents against IAV infection. In the present study, we selected a single-stranded DNA aptamer specific to the IAV NS1 protein after 15 cycles of systematic evolution of ligands by exponential enrichment (SELEX) procedure and examined the ability of the selected aptamer to inhibit the function of NS1. The selected aptamer binds to NS1 with a Kd of 18.91±3.95nM and RNA binding domain of NS1 is determined to be critical for the aptamer binding. The aptamer has a G-rich sequence in the random sequence region and forms a G-quadruplex structure. The localization of the aptamer bound to NS1 in cells was determined by confocal images, and flow cytometry analysis further demonstrated that the selected aptamer binds specifically to NS1. In addition, luciferase reporter gene assay, quantitative RT-PCR, and enzyme-linked immunosorbent assay (ELISA) experiments demonstrated that the selected aptamer had the ability to induce IFN-β by suppressing the function of NS1. Importantly, we also found that the selected aptamer was able to inhibit the viral replication without affecting cell viability. These results indicate that the selected ssDNA aptamer has strong potential to be further developed as a therapeutic agent against IAV.
Department of Bio and Nanochemistry, Kookmin University, Seoul 136-702, Republic of Korea.
Hye-Min
HM
Woo
Ki-Sun
KS
Kim
Jin-Moo
JM
Lee
Hee-Sup
HS
Shim
Seong-Je
SJ
Cho
Won-Kyu
WK
Lee
Hyuk Wan
HW
Ko
Young-Sam
YS
Keum
Soo-Youl
SY
Kim
Prabuddha
P
Pathinayake
Chul-Joong
CJ
Kim
Yong-Joo
YJ
Jeong
D000818:Animals; D000998:Antiviral Agents / Q000302:isolation & purification / Q000378:metabolism*; D052157:Aptamers, Nucleotide / Q000302:isolation & purification / Q000378:metabolism*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004277:DNA, Single-Stranded / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects* / Q000276:immunology / Q000502:physiology; D007372:Interferons / Q000096:biosynthesis* / Q000276:immunology; D007700:Kinetics; D051379:Mice; D011485:Protein Binding; D052156:SELEX Aptamer Technique; D017361:Viral Nonstructural Proteins / Q000378:metabolism*; D014779:Virus Replication / Q000187:drug effects
D000998:Antiviral Agents; D052157:Aptamers, Nucleotide; D004277:DNA, Single-Stranded; C085820:INS1 protein, influenza virus; D017361:Viral Nonstructural Proteins; D007372:Interferons
Aptamer; G-quadruplex; Influenza virus; Interferon; NS1