Identification of potent inhibitors of arenavirus and SARS-CoV-2 exoribonucleases by fluorescence polarization assay

Sergio Hernández (1) , Mikael Feracci (1) , Carolina Trajano de Jesus (1) , Priscila El Kazzi (1) , Rafik Kaci (1) , Laura Garlatti (1) , Clemence Mondielli (2) , Fabrice Bailly (3) , Philippe Cotelle (3, 4) , Franck Touret (5) , Xavier de Lamballerie (5) , Bruno Coutard (6) , Etienne Decroly (1) , Bruno Canard (1) , François Ferron (1) , Karine Alvarez (1)

1 AFMB - Architecture et fonction des macromolécules biologiques
2 Evotec [Toulouse]
3 LilNCog - Lille Neurosciences & Cognition - U 1172
4 Centrale Lille
5 UVE - Unité des Virus Emergents
6 IHU Marseille - Institut Hospitalier Universitaire Méditerranée Infection

Viral exoribonucleases are uncommon in the world of RNA viruses. To date, they have only been identified in the Arenaviridae and the Coronaviridae families. The exoribonucleases of these viruses play a crucial role in the pathogenicity and interplay with host innate immune response. Moreover, coronaviruses exoribonuclease is also involved in a proofreading mechanism ensuring the genetic stability of the viral genome. Because of their key roles in virus life cycle, they constitute attractive target for drug design. Here we developed a sensitive, robust and reliable fluorescence polarization assay to measure the exoribonuclease activity and its inhibition in vitro. The effectiveness of the method was validated on three different viral exoribonucleases, including SARS-CoV-2, Lymphocytic Choriomeningitis and Machupo viruses. We performed a screening of a focused library consisting of 113 metal chelators. Hit compounds were recovered with an IC50 at micromolar level. We confirmed 3 hits in SARS-CoV-2 infected Vero-E6 cells.

Mots clés: Exoribonuclease activity; Fluorescence polarization; Screening; Inhibitors; IC50; Cellular assays; Phosphohydrolase activity; Arenaviridae; Coronaviridae

Domaines: Virologie

Sergio Hernández, Mikael Feracci, Carolina Trajano de Jesus, Priscila El Kazzi, Rafik Kaci, et al.. Identification of potent inhibitors of arenavirus and SARS-CoV-2 exoribonucleases by fluorescence polarization assay. Antiviral Research, 2022, 204, pp.105364. ⟨10.1016/j.antiviral.2022.105364⟩. ⟨hal-03860671⟩