Ebola virus is among the deadliest viruses known and has caused on ongoing and sustained epidemic in Western Africa 2013-2015. The mysteries behind Ebola virus RNA transcription, replication and viral assembly remain mysteries in part, because no high- resolution structural models yet exist by which we may interpret these processes. The mission of this project is to define the structural and biochemical mechanisms governing Ebola virus RNA synthesis and viral assembly. The viral nucleocapsid is a multi-protein-RNA complex at the core of each virion that serves as a molecular machine to synthesize and encapsidate new copies of the viral RNA genome. The viral proteins in this machine have both positive and negative influences on viral RNA synthesis and control the balance of transcription and replication. Understanding the structures, protein-protein interactions, and assemblies of this nucleocapsid machine is key to development of antivirals. However, current low resolution models of the nucleocapsid present conflicting models. Here, we propose complementary crystallographic analysis of each complex that builds the nucleocapsid (NP-RNA, NP-VP35, NP-VP24, NP-VP30 and NP-VP40), combined with high-resolution electron microscopy reconstructions of assembled nucleocapsids. The EM reconstructions will be achieved using state-of-the-art instrumentation, innovative techniques, and high-quality purified samples, and the structural findings will be supported by biochemical, biophysical and functional analysis. Importantly, crystals are in hand for nearly all proposed complexes and functional assays are operational in the laboratory. The resulting structures of the viral nucleocapsid and its component assemblies will transform our understanding of the assembly and replication of Ebola and emerging filoviruses. Further, the results of this proposal will provide roadmaps for functional analysis of these viruses as well as strategies for development of antivirals to defend human populations against them.

Public Health Relevance

Ebola virus can be up to 90% lethal and is responsible for the ongoing epidemic in Western Africa. This project will provide molecular images of the viral nucleocapsid, will illuminate how the virus assembles and replicates, and will provide blueprints for development of antiviral drugs.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI118016-02
Application #
9228308
Study Section
Special Emphasis Panel (ZRG1-IDM-B (02)M)
Program Officer
Repik, Patricia M
Project Start
2016-03-01
Project End
2020-02-29
Budget Start
2017-03-01
Budget End
2018-02-28
Support Year
2
Fiscal Year
2017
Total Cost
$503,705
Indirect Cost
$242,040
Name
Scripps Research Institute
Department
Type
Research Institutes
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Bruhn, Jessica F; Kirchdoerfer, Robert N; Urata, Sarah M et al. (2017) Crystal Structure of the Marburg Virus VP35 Oligomerization Domain. J Virol 91:
Kirchdoerfer, Robert N; Moyer, Crystal L; Abelson, Dafna M et al. (2016) The Ebola Virus VP30-NP Interaction Is a Regulator of Viral RNA Synthesis. PLoS Pathog 12:e1005937
Kirchdoerfer, Robert N; Abelson, Dafna M; Li, Sheng et al. (2015) Assembly of the Ebola Virus Nucleoprotein from a Chaperoned VP35 Complex. Cell Rep 12:140-149
Bruhn, Jessica F; Barnett, Katherine C; Bibby, Jaclyn et al. (2014) Crystal structure of the nipah virus phosphoprotein tetramerization domain. J Virol 88:758-62