The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), urgently needs effective prophylactic and therapeutic drugs. RNA-dependent RNA polymerase (RdRp), essential for replicating and transcribing a viral RNA genome, is highly conserved in coronaviruses; thus, it is a potential target for inhibiting coronavirus infection. In this study, we generated the cell-based SARS-CoV-2 RdRp activity assay system by modifying a previously reported cell-based MERS-CoV RdRp activity assay system to screen for SARS-CoV-2 RdRp inhibitors. The assay system consisted of an expression plasmid encoding SARS-CoV-2 RdRp and an RdRp activity reporter plasmid. RdRp activity in the cells could be conveniently detected by luminescence after transfection. We confirmed that SARS-CoV-2 RdRp replicated double-stranded RNA using immunofluorescence staining and the inhibition of RdRp activity by remdesivir and lycorine using this system. Moreover, the Z-factor of this system was calculated to be 0.798, suggesting the reproducibility and reliability of the high-throughput screening system. Finally, we screened nucleoside and nucleotide analogs and identified adefovir dipivoxil, emtricitabine, telbivudine, entecavir hydrate, moroxydine and rifampin as novel SARS-CoV-2 RdRp inhibitors and therapeutic candidates for COVID-19 This system provides an effective high-throughput screening system platform for developing potential prophylactic and therapeutic drugs for COVID-19 and emerging coronavirus infections.
【저자키워드】 COVID-19, SARS-CoV-2, Therapeutics, Remdesivir, RdRP, RNA-dependent RNA polymerase, rifampin, Cepharanthine, emtricitabine, telbivudine, lycorine, adefovir dipivoxil, entecavir hydrate, moroxydine, 【초록키워드】 Coronavirus infection, coronavirus, reliability, COVID-19 pandemic, drugs, Prophylactic, MERS-CoV, inhibitors, Coronavirus infections, therapeutic, immunofluorescence, expression, platform, Luminescence, SARS-CoV-2 RdRp, nucleotide, double-stranded RNA, Plasmid, acute respiratory syndrome, this system, candidate, viral RNA genome, reproducibility, staining, effective, Cell, caused, conserved, reported, screened, calculated, provide, replicated, inhibiting, reporter plasmid, SARS-CoV-2 RdRp inhibitor, therapeutic drug, Z-factor, 【제목키워드】 activity, SARS-CoV-2 RdRp, System,