Small-molecule ligands can inhibit -1 programmed ribosomal frameshifting in a broad spectrum of coronaviruses

Munshi, S.; Neupane, K.; Ileperuma, S. M.; Halma, M. T.; Kelly, J. A.; Halpern, C. F.; Dinman, J. D.; Loerch, S.; Woodside, M. T.

doi:10.1101/2021.08.06.455424

bioRxiv · 10.1101/2021.08.06.455424

Small-molecule ligands can inhibit -1 programmed ribosomal frameshifting in a broad spectrum of coronaviruses

Munshi, S.·Neupane, K.·Ileperuma, S. M.·Halma, M. T.·Kelly, J. A.·Halpern, C. F.·Dinman, J. D.·Loerch, S.·Woodside, M. T.

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Abstract

Recurrent outbreaks of novel zoonotic coronavirus (CoV) diseases since 2000 have high-lighted the importance of developing therapeutics with broad-spectrum activity against CoVs. Because all CoVs use -1 programmed ribosomal frameshifting (-1 PRF) to control expression of key viral proteins, the frameshift signal in viral mRNA that stimulates -1 PRF provides a promising potential target for such therapeutics. To test the viability of this strategy, we explored a group of 6 small-molecule ligands, evaluating their activity against the frameshift signals from a panel of representative bat CoVs--the most likely source of future zoonoses--as well as SARS-CoV-2 and MERS-CoV. We found that whereas some ligands had notable activity against only a few of the frameshift signals, the serine protease inhibitor nafamostat suppressed -1 PRF significantly in several of them, while having limited to no effect on -1 PRF caused by frameshift signals from other viruses used as negative controls. These results suggest it is possible to find small-molecule ligands that inhibit -1 PRF specifically in a broad spectrum of CoVs, establishing the frameshift signal as a viable target for developing pan-coronaviral therapeutics.

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Munshi, S., Neupane, K., Ileperuma, S. M., Halma, M. T., Kelly, J. A., Halpern, C. F., Dinman, J. D., Loerch, S., Woodside, M. T.. 2021-08-06. Small-molecule ligands can inhibit -1 programmed ribosomal frameshifting in a broad spectrum of coronaviruses. https://doi.org/10.1101/2021.08.06.455424

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