title: Antibacterial peptide defensin is involved in midgut immunity of the soft tick, Ornithodoros moubata.
abstract: Two defensin genes A and B were previously demonstrated to be up-regulated by blood feeding in the soft tick, Ornithodoros moubata [Nakajima et al. (2001) Two isoforms of a member of the arthropod defensin family from the soft tick, Ornithodoros moubata (Acari: Argasidae). Insect Biochem Mol Biol 31: 747-751]. In this study, two defensin isoforms C and D similar to defensins A and B were newly cloned. A total of four defensins have been identified in O. moubata. All four Ornithodoros defensins are coded as prepro-defensins. Ornithodoros defensin genes consist of four exons and three introns, an organization reported in mussel defensins but not insect defensins. Ornithodoros defensin C and D genes are predominantly expressed in the midgut and up-regulated in response to blood feeding. The mature peptide of the previously cloned Ornithodoros defensin A was purified from the midgut lumen, indicating defensin is secreted into the midgut. These findings confirm the involvement of Ornithodoros defensin in midgut immunity.
authors.affiliation: Institute of Agriculture and Forestry, University of Tsukuba, Tsukuba, Ibaraki, Japan. yamakawa@nias.affrc.go.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Nakajima
authors.forename: A
authors.initials: A
authors.lastname: van der Goes van Naters-Yasui
authors.forename: D
authors.initials: D
authors.lastname: Taylor
authors.forename: M
authors.initials: M
authors.lastname: Yamakawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D017931:DNA Primers; D023082:Defensins / Q000235:genetics*; D005091:Exons; D007438:Introns; D008969:Molecular Sequence Data; D026861:Ornithodoros / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D010802:Phylogeny; D020033:Protein Isoforms / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
chemical_list: D017931:DNA Primers; D023082:Defensins; D020033:Protein Isoforms; C058181:insect defensin A