title: Ixodes ricinus and Its Endosymbiont Midichloria mitochondrii: A Comparative Proteomic Analysis of Salivary Glands and Ovaries.
abstract: Hard ticks are hematophagous arthropods that act as vectors of numerous pathogenic microorganisms of high relevance in human and veterinary medicine. Ixodes ricinus is one of the most important tick species in Europe, due to its role of vector of pathogenic bacteria such as Borrelia burgdorferi and Anaplasma phagocytophilum, of viruses such as tick borne encephalitis virus and of protozoans as Babesia spp. In addition to these pathogens, I. ricinus harbors a symbiotic bacterium, Midichloria mitochondrii. This is the dominant bacteria associated to I. ricinus, but its biological role is not yet understood. Most M. mitochondrii symbionts are localized in the tick ovaries, and they are transmitted to the progeny. M. mitochondrii bacteria have however also been detected in the salivary glands and saliva of I. ricinus, as well as in the blood of vertebrate hosts of the tick, prompting the hypothesis of an infectious role of this bacterium. To investigate, from a proteomic point of view, the tick I. ricinus and its symbiont, we generated the protein profile of the ovary tissue (OT) and of salivary glands (SG) of adult females of this tick species. To compare the OT and SG profiles, 2-DE profiling followed by LC-MS/MS protein identification were performed. We detected 21 spots showing significant differences in the relative abundance between the OT and SG, ten of which showed 4- to 18-fold increase/decrease in density. This work allowed to establish a method to characterize the proteome of I. ricinus, and to detect multiple proteins that exhibit a differential expression profile in OT and SG. Additionally, we were able to use an immunoproteomic approach to detect a protein from the symbiont. Finally, the method here developed will pave the way for future studies on the proteomics of I. ricinus, with the goals of better understanding the biology of this vector and of its symbiont M. mitochondrii.
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Di Venere
authors.affiliation: Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Fumagalli
authors.affiliation: Department of Veterinary Science and Public Health, University of Milan, Milan, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Cafiso
authors.affiliation: Department of Biology and Biotechnology, University of Pavia, Pavia, Italy; School of Bioscience and Veterinary Medicine, University of Camerino, Camerino, Italy.
authors.forename: Leone
authors.initials: L
authors.lastname: De Marco
authors.affiliation: Department of Veterinary Science and Public Health, University of Milan, Milan, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Epis
authors.affiliation: INRA, UMR1300 Biologie, Epidémiologie et Analyse de Risque en santé animale, CS 40706, Nantes, France; LUNAM Université, Oniris, Ecole nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique, UMR BioEpAR, Nantes, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Plantard
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Bardoni
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Salvini
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Viglio
authors.affiliation: Department of Veterinary Science and Public Health, University of Milan, Milan, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bazzocchi
authors.affiliation: Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Iadarola
authors.affiliation: Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Sassera
mesh_terms: D000818:Animals; D015153:Blotting, Western; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006863:Hydrogen-Ion Concentration; D018884:Ixodes / Q000378:metabolism* / Q000469:parasitology; D010053:Ovary / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D040901:Proteomics; D012287:Rickettsiaceae / Q000378:metabolism*; D012469:Salivary Glands / Q000378:metabolism*