title: Cross-Species Interferon Signaling Boosts Microbicidal Activity within the Tick Vector.
abstract: Evolution of hematophagy in blood-sucking parasites likely involves communication with their hosts. We find that Ixodes ticks are responsive to IFNγ acquired in a blood meal from mice infected with the Lyme disease-causing bacteria Borrelia burgdorferi, leading to induction of antimicrobial responses. Ixodes ticks parasitizing B. burgdorferi-infected mice upregulated an I. scapularis Rho-like GTPase (IGTPase). IGTPase knockdown enhanced B. burgdorferi levels in post-fed ticks, suggesting this protein controls spirochete survival. Notably, IGTPase was only induced during pathogen acquisition from mice and not upon transmission to naive hosts. Microinjection of ticks with IFNγ induced IGTPase, and ticks parasitizing IFNγ knockout mice, failed to upregulate IGTPase. Additionally, ticks lacking the transcription factor STAT, which signals downstream of IFNγ, did not induce IGTPase. IGTPase expression induced antimicrobial peptides, including Dae2, previously shown to inhibit B. burgdorferi. These results identify an interspecies signaling cascade allowing ticks to detect invading bacteria and mount microbicidal responses.
authors.affiliation: Department of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
authors.forename: Alexis A
authors.initials: AA
authors.lastname: Smith
authors.affiliation: CIC bioGUNE, 48160 Derio, Bizkaia, Spain.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Navasa
authors.affiliation: Department of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
authors.forename: Cara N
authors.initials: CN
authors.lastname: Wilder
authors.affiliation: Department of Microbiology, Faculty of Veterinary Medicine, Ondokuz Mayis University, Samsun 55139, Turkey.
authors.forename: Ozlem
authors.initials: O
authors.lastname: Buyuktanir
authors.affiliation: Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.
authors.forename: Adriana
authors.initials: A
authors.lastname: Marques
authors.affiliation: CIC bioGUNE, 48160 Derio, Bizkaia, Spain; Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Bizkaia, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Anguita
authors.affiliation: Department of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA; Virginia-Maryland Regional College of Veterinary Medicine, College Park, MD 20742, USA. Electronic address: upal@umd.edu.
authors.forename: Utpal
authors.initials: U
authors.lastname: Pal
mesh_terms: D000818:Animals; D001769:Blood / Q000276:immunology* / Q000382:microbiology; D025065:Borrelia burgdorferi / Q000276:immunology*; D005247:Feeding Behavior; D055785:Gene Knockdown Techniques; D007113:Immunity, Innate; D007372:Interferons / Q000378:metabolism*; D018884:Ixodes / Q000276:immunology / Q000382:microbiology / Q000502:physiology*; D008809:Mice, Inbred C3H; D018345:Mice, Knockout; D020559:Monomeric GTP-Binding Proteins / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D007372:Interferons; D020559:Monomeric GTP-Binding Proteins