Download MendeleyCovalent inhibition of the SARS-CoV-2 NiRAN domain via an active-site cysteine.
Hernandez, G., Osinski, A., Majumdar, A., Eitson, J.L., Antczak, M., Pawlowski, K., Niederstrasser, H., Servage, K.A., Posner, B., Schoggins, J.W., Ready, J.M., Tagliabracci, V.S.(2025) J Biological Chem 301: 108378-108378
- PubMed: 40049411
- DOI: https://doi.org/10.1016/j.jbc.2025.108378
- Primary Citation of Related Structures:
9CGV - PubMed Abstract:
The kinase-like NiRAN domain of nsp12 in SARS-CoV-2 catalyzes the formation of the 5' RNA cap structure. This activity is required for viral replication, offering a new target for the development of antivirals. Here, we develop a high-throughput assay to screen for small molecule inhibitors targeting the SARS-CoV-2 NiRAN domain. We identified NCI-2, a compound with a reactive chloromethyl group that covalently binds to an active site cysteine (Cys53) in the NiRAN domain, inhibiting its activity. NCI-2 can enter cells, bind to, and inactivate ectopically expressed nsp12. A cryo-EM reconstruction of the SARS-CoV-2 replication-transcription complex (RTC) bound to NCI-2 offers a detailed structural blueprint for rational drug design. Although NCI-2 showed limited potency against SARS-CoV-2 replication in cells, our work lays the groundwork for developing more potent and selective inhibitors targeting the NiRAN domain. This approach presents a promising therapeutic strategy for effectively combating COVID-19 and potentially mitigating future coronavirus outbreaks.
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
Organizational Affiliation:
