UPR 9022 CNRS
The CNRS Research Unit (UPR 9022 CNRS), “Immune Response and Development in Insects” is one of three laboratories hosted by the Institute of Molecular and Cellular Biology located on the central campus of the University of Strasbourg, France.
The research of UPR 9022 focuses on the cellular and molecular bases of the potent immune system of invertebrates, using both the models of the fruit fly Drosophila melanogaster and the mosquito, Anopheles. These models have emerged in recent years as tools for the study of innate immunity and host responses against pathogens or parasites like plasmodium, the causative agent of malaria.
Animal defence against infections is primarily based on the innate immune response, which activates the adaptive immune response in vertebrates. Starting with our discovery of the involvement of the Toll receptor in the defence against fungal infections, which led to the identification of the role of the Toll-like receptors (TLRs) in mammalian immunity, numerous studies have now established Drosophila as an excellent model for the dissection of the innate immune response. Also, the evolutionary conservation with the mammals and the large number of technical tools available, not the least being genetics, has established Drosophila as a model for an increasing number of human diseases.
The Drosophila immune response relies on multifaceted defence mechanisms consisting in humoral, cellular and epithelial responses. Additionaly, proteolytic cascades are activated in the hemolymph leading to coagulation and melanization of the wound. During the past years, our research has mainly focused on the humoral arm of this response.
The Drosophila humoral immune response can discriminate between different classes of microorganisms and activate appropriate defence mechanisms via two signalling pathways. Gram-positive bacteria and fungi activate, through circulating receptors and a proteolytic cascade, the cytokine-like Spaetzle protein, which then activates the Toll pathway. Gram-negative bacterial infections are sensed by membrane bound receptors that activate the IMD pathway. Activation of both pathways leads to the nuclear translocation of an NF-κB-like transcription factor and the transient synthesis of antimicrobial peptides that are predominantly active against the inducing pathogens.
- Cytokine Diedel and a viral homologue suppress the IMD pathway in Drosophila
PNAS, 113 (3), pp. 698–703, 2016.
- Sequence-independent characterization of viruses based on the pattern of viral small RNAs produced by the host Nucleic Acids Res., 43 (13), 2015.
Sensing viral RNAs by Dicer/RIG-I like ATPases across species Curr. Opin. Immunol., 32 , 2015.