{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T15:59:52Z","timestamp":1790870392283,"version":"4.1.0"},"reference-count":40,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,7,27]],"date-time":"2020-07-27T00:00:00Z","timestamp":1595808000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008783","name":"National Research Council of Science and Technology","doi-asserted-by":"publisher","award":["CRC-16-01-KRICT, NSN1621350, NST-KIOM Postdoctoral Fellowship for YS"],"award-info":[{"award-number":["CRC-16-01-KRICT, NSN1621350, NST-KIOM Postdoctoral Fellowship for YS"]}],"id":[{"id":"10.13039\/501100008783","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19) are emerging zoonotic diseases caused by coronavirus (CoV) infections. The viral RNA-dependent RNA polymerase (RdRp) has been suggested as a valuable target for antiviral therapeutics because the sequence homology of CoV RdRp is highly conserved. We established a cell-based reporter assay for MERS-CoV RdRp activity to test viral polymerase inhibitors. The cell-based reporter system was composed of the bicistronic reporter construct and the MERS-CoV nsp12 plasmid construct. Among the tested nine viral polymerase inhibitors, ribavirin, sofosbuvir, favipiravir, lamivudine, zidovudine, valacyclovir, vidarabine, dasabuvir, and remdesivir, only remdesivir exhibited a dose-dependent inhibition. Meanwhile, the Z-factor and Z\u2032-factor of this assay for screening inhibitors of MERS-CoV RdRp activity were 0.778 and 0.782, respectively. Ribavirin and favipiravir did not inhibit the MERS-CoV RdRp activity, and non-nucleoside HCV RdRp inhibitor, dasabuvir, partially inhibited MERS-CoV RdRp activity. Taken together, the cell-based reporter assay for MERS-CoV RdRp activity confirmed remdesivir as a direct inhibitor of MERS-CoV RdRp in cells. A cell-based MERS-CoV RdRp activity reporter assay is reliable and accurate for screening MERS-CoV RdRp-specific inhibitors. It may provide a valuable platform for developing antiviral drugs for emerging CoV infections.<\/jats:p>","DOI":"10.3390\/jcm9082399","type":"journal-article","created":{"date-parts":[[2020,7,30]],"date-time":"2020-07-30T03:36:38Z","timestamp":1596080198000},"page":"2399","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["A Cell-Based Reporter Assay for Screening Inhibitors of MERS Coronavirus RNA-Dependent RNA Polymerase Activity"],"prefix":"10.3390","volume":"9","author":[{"given":"Jung Sun","family":"Min","sequence":"first","affiliation":[{"name":"Herbal Medicine Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"},{"name":"Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geon-Woo","family":"Kim","sequence":"additional","affiliation":[{"name":"Herbal Medicine Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"},{"name":"Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0942-8164","authenticated-orcid":false,"given":"Sunoh","family":"Kwon","sequence":"additional","affiliation":[{"name":"Herbal Medicine Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"},{"name":"Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9916-1418","authenticated-orcid":false,"given":"Young-Hee","family":"Jin","sequence":"additional","affiliation":[{"name":"Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea"},{"name":"KM Application Center, Korea Institute of Oriental Medicine, Daegu 41062, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S2260","DOI":"10.21037\/jtd.2018.03.80","article-title":"Current understanding of middle east respiratory syndrome coronavirus infection in human and animal models","volume":"10","author":"Wang","year":"2018","journal-title":"J. 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