A fluorescence-based high throughput-screening assay for the SARS-CoV RNA synthesis complex

Area of Science:

• Virology
• Drug Discovery
• Biochemistry

Background:

• The emergence of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) in 2003 highlighted the threat of novel human coronaviruses.
• Conserved viral enzymes, such as RNA-dependent RNA polymerases, are key targets for antiviral therapies.
• The high homology between SARS-CoV and SARS-CoV-2 RNA synthesis machinery suggests shared vulnerabilities.

Purpose of the Study:

• To establish a high-throughput screening (HTS) assay for identifying inhibitors of coronavirus RNA synthesis.
• To leverage the conserved nature of SARS-CoV replication enzymes for broader antiviral applications.
• To accelerate the discovery of potential drug candidates against SARS-CoV-2.

Main Methods:

• Purification of a highly active Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) replication/transcription complex (RTC).
• Development and implementation of a high-throughput screening assay utilizing the purified SARS-CoV RTC.
• Screening of a chemical library comprising 1520 FDA-approved drugs.

Main Results:

• Demonstration of the assay's robustness in identifying potential inhibitors.
• Successful screening of a library of FDA-approved drugs against the SARS-CoV RTC.
• Identification of compounds that may inhibit coronavirus RNA synthesis.

Conclusions:

• The developed HTS assay is effective for discovering coronavirus RNA synthesis inhibitors.
• The conserved nature of SARS-CoV replication machinery allows for the identification of broad-spectrum antiviral compounds.
• This platform can expedite drug discovery efforts against emerging viral threats like SARS-CoV-2, enhancing pandemic preparedness.