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bioRxiv · 10.1101/2021.02.03.429625

A high-throughput radioactivity-based assay for screening SARS-CoV-2 nsp10-nsp16 complex

Khalili Yazdi, A.·Li, F.·Devkota, K.·Perveen, S.·Ghiabi, P.·Hajian, T.·Bolotokova, A.·Vedadi, M.
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Abstract

Frequent outbreaks of novel coronaviruses (CoVs), highlighted by the current SARS-CoV-2 pandemic, necessitate the development of therapeutics that could be easily and effectively administered world-wide. The conserved mRNA-capping process enables CoVs to evade their host immune system and is a target for antiviral development. Nonstructural protein (nsp) 16 in complex with nsp10 catalyzes the final step of coronaviral mRNA-capping through its 2-O-methylation activity. Like other methyltransferases, SARS-CoV-2 nsp10-nsp16 complex is druggable. However, the availability of an optimized assay for high-throughput screening (HTS) is an unmet need. Here, we report the development of a radioactivity-based assay for methyltransferase activity of nsp10-nsp16 complex in a 384-well format, and kinetic characterization, and optimization of the assay for HTS (Z'-factor: 0.83). Considering the high conservation of nsp16 across known CoV species, the potential inhibitors targeting SARS-CoV-2 nsp10-nsp16 complex may also be effective against other emerging pathogenic CoVs.

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Khalili Yazdi, A., Li, F., Devkota, K., Perveen, S., Ghiabi, P., Hajian, T., Bolotokova, A., Vedadi, M.. 2021-02-03. A high-throughput radioactivity-based assay for screening SARS-CoV-2 nsp10-nsp16 complex. https://doi.org/10.1101/2021.02.03.429625

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