tetano
Editor, Senior Moderator
Sci Rep
. 2025 May 26;15(1):18443.
doi: 10.1038/s41598-025-03813-y. Construction and validation of a cell based reporter assay for identifying inhibitors of SARS coronavirus 2 RNA dependent RNA polymerase activity
Eunjeong Kang[SUP] #[/SUP][SUP] 1 [/SUP], Haelim Yoon[SUP] #[/SUP][SUP] 1 [/SUP], Junho Lee[SUP] 1 [/SUP], JinAh Lee[SUP] 2 [/SUP], Seungtaek Kim[SUP] 2 [/SUP], Inseong Jo[SUP] 3 [/SUP], Soo Bong Han[SUP] 3 4 [/SUP], Dae Gwin Jeong[SUP] 5 [/SUP], Sayeon Cho[SUP] 6 [/SUP]
Affiliations
Targeting RNA-dependent RNA polymerase (RdRp), a highly conserved enzyme essential for SARS coronavirus 2 (SARS-CoV-2) replication and transcription, represents a promising antiviral strategy due to its lower mutation rate than structural proteins such as Spike. This study introduces a cell-based assay system for screening potential SARS-CoV-2 RdRp inhibitors, contributing to ongoing efforts to identify effective antiviral agents. The assay utilizes a reporter vector containing the 3' untranslated region (UTR), luciferase reporter gene, and 5' UTR gene, sequentially arranged in reverse under the control of the cytomegalovirus promoter in the pcDNA3.1 vector. Co-transfection with SARS-CoV-2 RdRp resulted an increase in luminescence-based quantification of RdRp activity, achieving a Z-factor of 0.605, indicative of high reproducibility and reliability for high-throughput screening. Established RdRp inhibitors, including remdesivir, molnupiravir, tenofovir, and sofosbuvir, significantly reduced reporter activity, with remdesivir exhibiting the strongest inhibition. A newly identified RdRp inhibitor was further validated through primer extension polymerase and NMPylation assays, along with virus-based experiments, confirming its inhibitory mechanism. These results highlight the utility of this screening system in identifying effective RdRp-targeting antivirals, reinforcing the strategic importance of RdRp inhibition in combating SARS-CoV-2 and emerging variants.
Keywords: Cell-based reporter assay; High-throughput screening; RdRp; SARS-CoV-2; SARS-CoV-2 RdRp inhibitor.
. 2025 May 26;15(1):18443.
doi: 10.1038/s41598-025-03813-y. Construction and validation of a cell based reporter assay for identifying inhibitors of SARS coronavirus 2 RNA dependent RNA polymerase activity
Eunjeong Kang[SUP] #[/SUP][SUP] 1 [/SUP], Haelim Yoon[SUP] #[/SUP][SUP] 1 [/SUP], Junho Lee[SUP] 1 [/SUP], JinAh Lee[SUP] 2 [/SUP], Seungtaek Kim[SUP] 2 [/SUP], Inseong Jo[SUP] 3 [/SUP], Soo Bong Han[SUP] 3 4 [/SUP], Dae Gwin Jeong[SUP] 5 [/SUP], Sayeon Cho[SUP] 6 [/SUP]
Affiliations
- PMID: 40419748
- DOI: 10.1038/s41598-025-03813-y
Targeting RNA-dependent RNA polymerase (RdRp), a highly conserved enzyme essential for SARS coronavirus 2 (SARS-CoV-2) replication and transcription, represents a promising antiviral strategy due to its lower mutation rate than structural proteins such as Spike. This study introduces a cell-based assay system for screening potential SARS-CoV-2 RdRp inhibitors, contributing to ongoing efforts to identify effective antiviral agents. The assay utilizes a reporter vector containing the 3' untranslated region (UTR), luciferase reporter gene, and 5' UTR gene, sequentially arranged in reverse under the control of the cytomegalovirus promoter in the pcDNA3.1 vector. Co-transfection with SARS-CoV-2 RdRp resulted an increase in luminescence-based quantification of RdRp activity, achieving a Z-factor of 0.605, indicative of high reproducibility and reliability for high-throughput screening. Established RdRp inhibitors, including remdesivir, molnupiravir, tenofovir, and sofosbuvir, significantly reduced reporter activity, with remdesivir exhibiting the strongest inhibition. A newly identified RdRp inhibitor was further validated through primer extension polymerase and NMPylation assays, along with virus-based experiments, confirming its inhibitory mechanism. These results highlight the utility of this screening system in identifying effective RdRp-targeting antivirals, reinforcing the strategic importance of RdRp inhibition in combating SARS-CoV-2 and emerging variants.
Keywords: Cell-based reporter assay; High-throughput screening; RdRp; SARS-CoV-2; SARS-CoV-2 RdRp inhibitor.