title: Draper/CED-1 mediates an ancient damage response to control inflammatory blood cell migration in vivo.
abstract: Tissue damage leads to a robust and rapid inflammatory response whereby leukocytes are actively drawn toward the wound. Hydrogen peroxide (H2O2) has been shown to be an immediate damage signal essential for the recruitment of these inflammatory blood cells to wound sites in both Drosophila and vertebrates [1, 2]. Recent studies in zebrafish have shown that wound-induced H2O2 is detected by the redox-sensitive Src family kinase (SFK) Lyn within the responding blood cells [3]. Here, we show the same signaling occurs in Drosophila inflammatory cells in response to wound-induced H2O2 with mutants for the Lyn homolog Src42A displaying impaired inflammatory migration to wounds. We go on to show that activation of Src42A is necessary to trigger a signaling cascade within the inflammatory cells involving the ITAM domain-containing protein Draper-I (a member of the CED-1 family of apoptotic cell clearance receptors) and a downstream kinase, Shark, that is required for migration to wounds. The Src42A-Draper-Shark-mediated signaling axis is homologous to the well-established SFK-ITAM-Syk-signaling pathway used in vertebrate adaptive immune responses. Consequently, our results suggest that adaptive immunoreceptor-signaling pathways important in distinguishing self from non-self appear to have evolved from a more-ancient damage response. Furthermore, this changes the role of H2O2 from an inflammatory chemoattractant to an activator signal that primes immune cells to respond to damage cues via the activation of damage receptors such as Draper.
authors.affiliation: Department of Infection and Immunity and Bateson Centre, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK. Electronic address: i.r.evans@sheffield.ac.uk.
authors.forename: Iwan Robert
authors.initials: IR
authors.lastname: Evans
authors.affiliation: School of Cellular and Molecular Medicine, Faculty of Medical Sciences, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK.
authors.forename: Frederico S L M
authors.initials: FS
authors.lastname: Rodrigues
authors.affiliation: Department of Infection and Immunity and Bateson Centre, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.
authors.forename: Emma Louise
authors.initials: EL
authors.lastname: Armitage
authors.affiliation: School of Cellular and Molecular Medicine, Faculty of Medical Sciences, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK. Electronic address: w.wood@bristol.ac.uk.
authors.forename: Will
authors.initials: W
authors.lastname: Wood
mesh_terms: D000818:Animals; D002465:Cell Movement; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology* / Q000235:genetics / Q000378:metabolism*; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029721:Drosophila Proteins; D008565:Membrane Proteins; C495322:drpr protein, Drosophila; C092552:Shark protein, Drosophila; D011505:Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src); C100382:Src42A protein, Drosophila