Ebola virus is a Category A virus and an emerging human pathogen that causes devastating outbreaks of hemorrhagic fever. Assembly and budding are important late events in the replication cycle of Ebola virus. While much has been learned regarding these dynamic and multifaceted stages of virus replication, the molecular mechanisms of assembly and budding remain unclear. This proposal focuses on the VP40 matrix protein of Ebola virus. Ebola VP40 protein contains late budding domains (L-domain) that play a key role in virus egress by mediating interactions with host proteins, such as tsg101. We hypothesize that host innate immune responses inhibit Ebola virus budding by targeting VP40 L-domain activity. Preliminary data implicate interferon stimulated gene 15 (ISG15) in inhibiting Ebola VP40 VLP budding. To test our hypothesis, we propose 3 Specific Aims: 1) To determine whether expression of ISG15 inhibits release of Ebola VP40 VLPs in an L-domain dependent manner, 2) To determine whether expression of ISG15 inhibits release of Ebola virus or VSV recombinants expressing Ebola virus L-domains, and 3) To determine whether expression of ISG15 inhibits Ebola VP40/host tsg101 interactions. Results from these studies should provide fundamental knowledge of how specific components of the innate immune response may inhibit Ebola virus budding, and provide the foundation for future studies to elucidate further the mechanisms and biological significance of these innate immune responses to Ebola virus infection. ? ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI077014-02
Application #
7497911
Study Section
Special Emphasis Panel (ZAI1-PA-I (S2))
Program Officer
Miller, Lara R
Project Start
2007-09-25
Project End
2011-08-31
Budget Start
2008-09-01
Budget End
2011-08-31
Support Year
2
Fiscal Year
2008
Total Cost
$193,134
Indirect Cost
Name
University of Pennsylvania
Department
Pathology
Type
Schools of Veterinary Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Okumura, Atsushi; Rasmussen, Angela L; Halfmann, Peter et al. (2015) Suppressor of Cytokine Signaling 3 Is an Inducible Host Factor That Regulates Virus Egress during Ebola Virus Infection. J Virol 89:10399-406
Liu, Yuliang; Lee, Michael S; Olson, Mark A et al. (2011) Bimolecular Complementation to Visualize Filovirus VP40-Host Complexes in Live Mammalian Cells: Toward the Identification of Budding Inhibitors. Adv Virol 2011:
Liu, Yuliang; Stone, Sasha; Harty, Ronald N (2011) Characterization of filovirus protein-protein interactions in mammalian cells using bimolecular complementation. J Infect Dis 204 Suppl 3:S817-24
Okumura, Atsushi; Pitha, Paula M; Yoshimura, Akihiko et al. (2010) Interaction between Ebola virus glycoprotein and host toll-like receptor 4 leads to induction of proinflammatory cytokines and SOCS1. J Virol 84:27-33
Liu, Yuliang; Harty, Ronald N (2010) Viral and host proteins that modulate filovirus budding. Future Virol 5:481-491
Harty, Ronald N (2009) No exit: targeting the budding process to inhibit filovirus replication. Antiviral Res 81:189-97
Harty, Ronald N; Pitha, Paula M; Okumura, Atsushi (2009) Antiviral activity of innate immune protein ISG15. J Innate Immun 1:397-404