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bioRxiv · 10.1101/2020.03.24.005900

Topoisomerase III-beta is required for efficient replication of positive-sense RNA viruses

Prasanth, K. R.·Hirano, M.·Fagg, W. S.·McAnarney, E.·Chan, S.·Xie, X.·Hage, A.·Pietzsch, C.·Bukreyev, A.·Rajsbaum, R.·Shi, P.-Y.·Bedford, M.·Bradrick, S.·Menachery, V. D.·Garcia-Blanco, M. A.
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Abstract

Based on genome-scale loss-of-function screens we discovered that Topoisomerase III-{beta} (TOP3B), a human topoisomerase that acts on DNA and RNA, is required for yellow fever virus and dengue virus-2 replication. Remarkably, we found that TOP3B is required for efficient replication of all positive-sense-single stranded RNA viruses tested, including SARS-CoV-2. While there are no drugs that specifically inhibit this topoisomerase, we posit that TOP3B is an attractive anti-viral target.

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Prasanth, K. R., Hirano, M., Fagg, W. S., McAnarney, E., Chan, S., Xie, X., Hage, A., Pietzsch, C., Bukreyev, A., Rajsbaum, R., Shi, P.-Y., Bedford, M., Bradrick, S., Menachery, V. D., Garcia-Blanco, M. A.. 2020-03-27. Topoisomerase III-beta is required for efficient replication of positive-sense RNA viruses. https://doi.org/10.1101/2020.03.24.005900

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