High-throughput Activity Assay for Screening Inhibitors of the SARS-CoV-2 Mac1 Macrodomain

Dasovich, M. A.; Zhou, J.; Thomas, A. G.; Goodman, J. A.; McPherson, R. L.; Jayabalan, A. K.; Busa, V. F.; Cheng, S.-J.; Murphy, B.; Redinger, K. R.; Tsukamoto, T.; Slusher, B. S.; Bosch, J.; Wei, J.; Leung, A.

doi:10.1101/2021.10.07.463234

bioRxiv · 10.1101/2021.10.07.463234

High-throughput Activity Assay for Screening Inhibitors of the SARS-CoV-2 Mac1 Macrodomain

Dasovich, M. A.·Zhou, J.·Thomas, A. G.·Goodman, J. A.·McPherson, R. L.·Jayabalan, A. K.·Busa, V. F.·Cheng, S.-J.·Murphy, B.·Redinger, K. R.·Tsukamoto, T.·Slusher, B. S.·Bosch, J.·Wei, J.·Leung, A.

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Abstract

Macrodomains are a class of conserved ADP-ribosylhydrolases expressed by viruses of pandemic concern, including coronaviruses and alphaviruses. Viral macrodomains are critical for replication and virus-induced pathogenesis; therefore, these enzymes are a promising target for antiviral therapy. However, no potent or selective viral macrodomain inhibitors currently exist, in part due to the lack of a high-throughput assay for this class of enzymes. Here, we developed a high-throughput ADP-ribosylhydrolase assay using the SARS-CoV-2 macrodomain Mac1. We performed a pilot screen which identified dasatinib and dihydralazine as ADP-ribosylhydrolase inhibitors. Importantly, dasatinib does not inhibit MacroD2, the closest Mac1 homolog in humans. Our study demonstrates the feasibility of identifying selective inhibitors based on ADP-ribosylhydrolase activity, paving the way for screening large compound libraries to identify improved macrodomain inhibitors and explore their potential as antiviral therapies for SARS-CoV-2 and future viral threats.

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Dasovich, M. A., Zhou, J., Thomas, A. G., Goodman, J. A., McPherson, R. L., Jayabalan, A. K., Busa, V. F., Cheng, S.-J., Murphy, B., Redinger, K. R., Tsukamoto, T., Slusher, B. S., Bosch, J., Wei, J., Leung, A.. 2021-10-07. High-throughput Activity Assay for Screening Inhibitors of the SARS-CoV-2 Mac1 Macrodomain. https://doi.org/10.1101/2021.10.07.463234

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