Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infections, morbidity, and mortality in infants and young children, the elderly, and immunocompromised individuals worldwide. Despite decades of intensive research, treatment options are limited and in need of improvement. Non-structural proteins 1 (NS1) and 2 (NS2) are multifunctional proteins that play critical roles in RSV virulence and pathogenesis. NS1/2 are involved in host immune suppression, including inhibition of Type I interferon (IFN) induction and signaling, as well as inhibition of the NF-?B pathway and apoptosis. Although many host factors are thought to be targeted by RSV NS1/2 protein, currently no structures of NS1 or NS2 are available. The lack of structural studies limits our knowledge and corresponding mechanistic insights into immune evasion facilitated by these non-structural proteins. Moreover, this gap in knowledge also restricts our ability to develop countermeasures. In order to address this gap, we will (a) develop a structural and mechanistic understanding of viral immune antagonists NS1/2 proteins and (b) characterize their interactions with IFN production and response signaling pathways, including IRF3, STAT1, and STAT2 using biochemical and structural methods. Findings from these studies will be tested in vivo to identify residues critical for immune antagonist function. Through these studies, we expect to define the molecular basis for how RSV NS1/2 contributes to immune evasion and identify new targets for therapeutic and antiviral development.

Public Health Relevance

Respiratory syncytial virus (RSV) is a major contributor to lower respiratory tract infections in infants and young children worldwide. There are major gaps in our understanding as to the mechanisms by which these viruses interact with host factors and evade immune responses. We will study interaction of the RSV non-structural proteins, NS1 and NS2, with cellular proteins, including RIG-I, IRF3, and STAT2, in order to shed light on these interactions and identify novel antiviral approaches.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI107056-05
Application #
9284383
Study Section
Virology - A Study Section (VIRA)
Program Officer
Kim, Sonnie
Project Start
2013-06-01
Project End
2019-05-31
Budget Start
2017-06-01
Budget End
2019-05-31
Support Year
5
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Washington University
Department
Pathology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Holze, Cathleen; Michaudel, ChloƩ; Mackowiak, Claire et al. (2018) Oxeiptosis, a ROS-induced caspase-independent apoptosis-like cell-death pathway. Nat Immunol 19:130-140
Johnson, Britney; VanBlargan, Laura A; Xu, Wei et al. (2018) Human IFIT3 Modulates IFIT1 RNA Binding Specificity and Protein Stability. Immunity 48:487-499.e5
Chanthamontri, C Ken; Jordan, David; Wang, Wenjie et al. (2018) Ebola Viral Protein 35 N-terminus is a Parallel Tetramer. Biochemistry :
Postler, Thomas S; Clawson, Anna N; Amarasinghe, Gaya K et al. (2017) Possibility and Challenges of Conversion of Current Virus Species Names to Linnaean Binomials. Syst Biol 66:463-473
Xu, Wei; Luthra, Priya; Wu, Chao et al. (2017) Ebola virus VP30 and nucleoprotein interactions modulate viral RNA synthesis. Nat Commun 8:15576
Liu, Gai; Nash, Peter J; Johnson, Britney et al. (2017) A Sensitive in Vitro High-Throughput Screen To Identify Pan-filoviral Replication Inhibitors Targeting the VP35-NP Interface. ACS Infect Dis 3:190-198
Luthra, Priya; Aguirre, Sebastian; Yen, Benjamin C et al. (2017) Topoisomerase II Inhibitors Induce DNA Damage-Dependent Interferon Responses Circumventing Ebola Virus Immune Evasion. MBio 8:
Chatterjee, Srirupa; Luthra, Priya; Esaulova, Ekaterina et al. (2017) Structural basis for human respiratory syncytial virus NS1-mediated modulation of host responses. Nat Microbiol 2:17101
Edwards, Megan R; Liu, Gai; Mire, Chad E et al. (2016) Differential Regulation of Interferon Responses by Ebola and Marburg Virus VP35 Proteins. Cell Rep 14:1632-1640
Leung, Daisy W; Amarasinghe, Gaya K (2016) When your cap matters: structural insights into self vs non-self recognition of 5' RNA by immunomodulatory host proteins. Curr Opin Struct Biol 36:133-41

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