TY - JOUR
T1 - Establishment of a Replicon Reporter of the Emerging Tick-Borne Bourbon Virus and Use It for Evaluation of Antivirals
AU - Hao, Siyuan
AU - Ning, Kang
AU - Wang, Xiaomei
AU - Wang, Jianke
AU - Cheng, Fang
AU - Ganaie, Safder S.
AU - Tavis, John E.
AU - Qiu, Jianming
N1 - Funding Information:
We are grateful to Dr. Zekun Wang and other members of the Qiu Laboratory for technical support and valuable discussions. We thank Dr. Wenjun Ma at Kansas State University for providing the pHW2000 plasmid. The following reagent was obtained through BEI Resources, NIAID, NIH: Bourbon Virus, Original, NR-50132. Funding. This study was supported by PHS grant AI144564 from the National Institute of Allergy and Infectious Diseases. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Publisher Copyright:
© Copyright © 2020 Hao, Ning, Wang, Wang, Cheng, Ganaie, Tavis and Qiu.
PY - 2020/9/8
Y1 - 2020/9/8
N2 - Bourbon virus (BRBV) was first isolated from a patient hospitalized at the University of Kansas Hospital in 2014. Since then, several deaths have been reported to be caused by BRBV infection in the Midwest and Southern United States. BRBV is a tick-borne virus that is widely carried by lone star ticks. It belongs to genus Thogotovirus of the Orthomyxoviridae family. Currently, there are no treatments or vaccines available for BRBV or thogotovirus infection caused diseases. In this study, we reconstituted a replicon reporter system, composed of plasmids expressing the RNA-dependent RNA polymerase (RdRP) complex (PA, PB1, and PB2), nucleocapsid (NP) protein, and a reporter gene flanked by the 3′ and 5′ untranslated region (UTR) of the envelope glycoprotein (GP) genome segment. By using the luciferase reporter, we screened a few small molecule compounds of anti-endonuclease that inhibited the nicking activity by parvovirus B19 (B19V) NS1, as well as FDA-approved drugs targeting the RdRP of influenza virus. Our results demonstrated that myricetin, an anti-B19V NS1 nicking inhibitor, efficiently inhibited the RdRP activity of BRBV and virus replication. The IC50 and EC50 of myricetin are 2.22 and 4.6 μM, respectively, in cells. Myricetin had minimal cytotoxicity in cells, and therefore the therapeutic index of the compound is high. In conclusion, the BRBV replicon system is a useful tool to study viral RNA replication and to develop antivirals, and myricetin may hold promise in treatment of BRBV infected patients.
AB - Bourbon virus (BRBV) was first isolated from a patient hospitalized at the University of Kansas Hospital in 2014. Since then, several deaths have been reported to be caused by BRBV infection in the Midwest and Southern United States. BRBV is a tick-borne virus that is widely carried by lone star ticks. It belongs to genus Thogotovirus of the Orthomyxoviridae family. Currently, there are no treatments or vaccines available for BRBV or thogotovirus infection caused diseases. In this study, we reconstituted a replicon reporter system, composed of plasmids expressing the RNA-dependent RNA polymerase (RdRP) complex (PA, PB1, and PB2), nucleocapsid (NP) protein, and a reporter gene flanked by the 3′ and 5′ untranslated region (UTR) of the envelope glycoprotein (GP) genome segment. By using the luciferase reporter, we screened a few small molecule compounds of anti-endonuclease that inhibited the nicking activity by parvovirus B19 (B19V) NS1, as well as FDA-approved drugs targeting the RdRP of influenza virus. Our results demonstrated that myricetin, an anti-B19V NS1 nicking inhibitor, efficiently inhibited the RdRP activity of BRBV and virus replication. The IC50 and EC50 of myricetin are 2.22 and 4.6 μM, respectively, in cells. Myricetin had minimal cytotoxicity in cells, and therefore the therapeutic index of the compound is high. In conclusion, the BRBV replicon system is a useful tool to study viral RNA replication and to develop antivirals, and myricetin may hold promise in treatment of BRBV infected patients.
KW - antivirals
KW - Bourbon virus
KW - replicon reporter
KW - RNA-dependent RNA polymerase
KW - thogotovirus
KW - tick-borne virus
UR - http://www.scopus.com/inward/record.url?scp=85091451362&partnerID=8YFLogxK
U2 - 10.3389/fmicb.2020.572631
DO - 10.3389/fmicb.2020.572631
M3 - Article
AN - SCOPUS:85091451362
SN - 1664-302X
VL - 11
JO - Frontiers in Microbiology
JF - Frontiers in Microbiology
M1 - 572631
ER -