Crimean-Congo haemorrhagic fever virus (CCHFV) is a tick-borne virus and causes severe, often fatal, human infections. Lacking licensed vaccines or drugs, CCHFV is a World Health Organization priority pathogen requiring urgent development of medical countermeasures 1,2 . The CCHFV Large (L) protein functions as the viral RNA-dependent RNA polymerase CCHFV-L, representing a promising antiviral target, and is among the largest viral polymerases in the order Bunyavirales. Here we define the cofactors required for CCHFV-L RNA synthesis in vitro, enabling capture and determination of elongating CCHFV-L-RNA complex structures. The structures show a markedly enlarged polymerase architecture, revealing that CCHFV-L RNA synthesis is accompanied by ordering of the polymerase peripheral domains. We also define how the baloxavir-derived experimental drug WXSH0208 (ref. 3 ) and the nucleoside analogue 2'-deoxy-2'-fluorocytidine 4,5 , which has nanomolar cellular potency, inhibit this polymerase through endonuclease inhibition and post-translocation chain termination, respectively. Together, these results should structurally guide rational optimization of inhibitors directed against CCHFV-L.
Organizational Affiliation:
State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
The Guangdong-Hong Kong-Macao Joint Laboratory for Cell Fate Regulation and Diseases, GMU-GIBH Joint School of Life Sciences, Guangdong Provincial Key Laboratory of Protein Modification and Disease, Guangzhou Medical University, Guangzhou, China.
University of Chinese Academy of Sciences, Beijing, China.
State Key Laboratory of Virology and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.
Department of Medicinal Chemistry, State Key Laboratory of Discovery and Utilization of Functional Components in Traditional Chinese Medicine, Shandong Key Laboratory of Druggability Optimization and Evaluation for Lead Compounds, Shandong Basic Science Special Academic Zone (Pharmacy), School of Pharmaceutical Sciences, Shandong University, Jinan, China.
Guangzhou National Laboratory, Guangzhou, China.
Tianjin Cisen Pharmaceutical Research Co. Ltd, Tianjin, China.
Departments of Microbiology and Immunology, College of Medicine, University of Illinois Chicago, Chicago, IL, USA.
State Key Laboratory of Virology and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China. dengzengqin@wh.iov.cn.
State Key Laboratory of Virology and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China. wangml@wh.iov.cn.
Department of Medicinal Chemistry, State Key Laboratory of Discovery and Utilization of Functional Components in Traditional Chinese Medicine, Shandong Key Laboratory of Druggability Optimization and Evaluation for Lead Compounds, Shandong Basic Science Special Academic Zone (Pharmacy), School of Pharmaceutical Sciences, Shandong University, Jinan, China. zhanpeng1982@sdu.edu.cn.
Guangzhou National Laboratory, Guangzhou, China. chen_xinwen@gzlab.ac.cn.
State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. chen_xinwen@gzlab.ac.cn.
State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, GIBH-CUHK Joint Research Laboratory on Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China. xiong_xiaoli@gzlab.ac.cn.
The Guangdong-Hong Kong-Macao Joint Laboratory for Cell Fate Regulation and Diseases, GMU-GIBH Joint School of Life Sciences, Guangdong Provincial Key Laboratory of Protein Modification and Disease, Guangzhou Medical University, Guangzhou, China. xiong_xiaoli@gzlab.ac.cn.
Guangzhou National Laboratory, Guangzhou, China. xiong_xiaoli@gzlab.ac.cn.
Download Mendeley
