Viruses with an RNA genome are important human pathogens and exhibit distinct genetic and immunological properties from DNA viruses. Plant and invertebrate hosts produce virus-derived small interfering RNAs (siRNAs) of 21-24 nucleotides in length to guide specific clearance of RNA viruses by RNA interference (RNAi). However, it has been unclear if the conserved RNAi pathway has a similar antiviral role in mammals. New findings described here and in two recent papers in Science by the principal investigator provide evidence for the induction of antiviral RNAi and specific sterilizing immunity in mice by a mosquito-transmissible positive-strand RNA virus. Preliminary studies also indicate a role for the viral suppression of RNAi in mouse infection and for a known innate immune sensor of RNA viruses in the biogenesis of the predominantly 22- nucleotide viral siRNAs. Using the established mouse model, a complementary set of studies is proposed to characterize the function and mechanism of the mammalian RNAi- mediated antiviral immunity. Moreover, possible regulatory roles of interferon signaling and the interferon-stimulated innate immune sensors of RNA viruses in the new form of mammalian antiviral immunity will be examined. These studies will likely open up a new area of research on the antiviral immunity mechanisms in mammals.

Public Health Relevance

The goal of this project is to characterize a new innate immunity mechanism that mammals use to defend themselves from viral infections. Understanding the antiviral mechanism may lead to the development of therapeutic interventions against viral diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
High Priority, Short Term Project Award (R56)
Project #
1R56AI110579-01A1
Application #
9014138
Study Section
Virology - B Study Section (VIRB)
Program Officer
Palker, Thomas J
Project Start
2015-03-15
Project End
2017-02-28
Budget Start
2015-03-15
Budget End
2017-02-28
Support Year
1
Fiscal Year
2015
Total Cost
Indirect Cost
Name
University of California Riverside
Department
Other Basic Sciences
Type
Earth Sciences/Resources
DUNS #
627797426
City
Riverside
State
CA
Country
United States
Zip Code
92521
Ding, Shou-Wei; Han, Qingxia; Wang, Jinyan et al. (2018) Antiviral RNA interference in mammals. Curr Opin Immunol 54:109-114
Jeffrey, Kate L; Li, Yang; Ding, Shou-Wei (2017) Reply to 'Questioning antiviral RNAi in mammals'. Nat Microbiol 2:17053
Li, Yang; Basavappa, Megha; Lu, Jinfeng et al. (2016) Induction and suppression of antiviral RNA interference by influenza A virus in mammalian cells. Nat Microbiol 2:16250