The objective of this project is to analyze host-defense mechanisms against viral infection in the model organism Drosophila melanogaster, and to do so in the light of concurrent studies of viral infection in mice, carried out by our colleagues in La Jolla and in Osaka. By studying the response of Drosophila to viral infection we will uncover evolutionarily conserved mechanisms of innate immunity that, together with the programs developed in the other participating laboratories, will help to unravel the essential aspects of the antiviral response in mammals. The project has two specific aims, which are based on the original results obtained by the laboratory in the past five years. The picture emerging from these studies is that of a complex, multi-faceted program of defense, essentially based on RNA interference and an inducible response, on which our knowledge is still fragmentary. In this new application, we aim to produce an integrative view of the sensing, signaling and effector mechanisms leading to resistance to virus infection in drosophila.
The first aim i s to conduct unbiased forward genetic screens to identify mutations that impair the antiviral response. The readout for the screens will be the viral load (using GFP-expressing recombinant viruses), and the survival to viral infection. We propose to take advantage of the technological breakthrough of SOLiD high throughput sequencing to rapidly identify the mutated genes in a cost effective manner by whole genome resequencing.
The second aim i s to characterize the role of three evolutionarily conserved pathways, namely RNAi, Toll and Imd, in antiviral defense in drosophila. The experimental strategy will be to identify by a powerful method combining the unparalleled affinity of avidin for biotin and the exquisite sensitivity of nanoLC-tandem mass spectrometry the molecules interacting with selected components of the RNA interference, Imd and Toll pathways. The composition of these complexes will be compared in cells either uninfected or infected by viruses replicating in different cytoplasmic locations. The function of the identified molecules will be characterized in cells and flies. In addition, we will study by live imaging in infected cells the interaction of the canonical molecules of the RNAi pathway (Dicer-2, R2D2 and AGO2) with viral RNAs.

Public Health Relevance

We anticipate that this project will allow us to reveal novel evolutionarily conserved pathways of host-defense, as we earlier did for Toll-like receptors. Understanding the molecular mechanisms of antiviral immunity in drosophila may also lead us to propose novel strategies to fight viral infections. Finally, this project is expected to shed light on the interaction between vector insects and the pathogenic arthropod- borne viruses they transmit to humans.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
5P01AI070167-08
Application #
8678819
Study Section
Special Emphasis Panel (ZAI1)
Project Start
Project End
Budget Start
2014-07-01
Budget End
2015-06-30
Support Year
8
Fiscal Year
2014
Total Cost
Indirect Cost
City
Dallas
State
TX
Country
United States
Zip Code
75390
Goto, Akira; Okado, Kiyoshi; Martins, Nelson et al. (2018) The Kinase IKK? Regulates a STING- and NF-?B-Dependent Antiviral Response Pathway in Drosophila. Immunity 49:225-234.e4
Maeda, Kazuhiko; Akira, Shizuo (2017) Regulation of mRNA stability by CCCH-type zinc-finger proteins in immune cells. Int Immunol 29:149-155
Satoh, Takashi; Nakagawa, Katsuhiro; Sugihara, Fuminori et al. (2017) Identification of an atypical monocyte and committed progenitor involved in fibrosis. Nature 541:96-101
Kozaki, Tatsuya; Komano, Jun; Kanbayashi, Daiki et al. (2017) Mitochondrial damage elicits a TCDD-inducible poly(ADP-ribose) polymerase-mediated antiviral response. Proc Natl Acad Sci U S A 114:2681-2686
Mager, Lukas Franz; Koelzer, Viktor Hendrik; Stuber, Regula et al. (2017) The ESRP1-GPR137 axis contributes to intestinal pathogenesis. Elife 6:
Mussabekova, Assel; Daeffler, Laurent; Imler, Jean-Luc (2017) Innate and intrinsic antiviral immunity in Drosophila. Cell Mol Life Sci 74:2039-2054
Kuhn, Lauriane; Majzoub, Karim; Einhorn, Evelyne et al. (2017) Definition of a RACK1 Interaction Network in Drosophila melanogaster Using SWATH-MS. G3 (Bethesda) 7:2249-2258
Takahama, Michihiro; Fukuda, Mitsunori; Ohbayashi, Norihiko et al. (2017) The RAB2B-GARIL5 Complex Promotes Cytosolic DNA-Induced Innate Immune Responses. Cell Rep 20:2944-2954
Lamiable, Olivier; Arnold, Johan; de Faria, Isaque Joao da Silva et al. (2016) Analysis of the Contribution of Hemocytes and Autophagy to Drosophila Antiviral Immunity. J Virol 90:5415-5426
Marques, João T; Imler, Jean-Luc (2016) The diversity of insect antiviral immunity: insights from viruses. Curr Opin Microbiol 32:71-76

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