title: Cysteine-rich antimicrobial peptides of the cattle tick Boophilus microplus: isolation, structural characterization and tissue expression profile.
abstract: Antimicrobial peptides (AMPs) are components of the immune system of both vertebrate and invertebrate animals. This study describes the isolation, primary structure, cDNA cloning, and tissue expression profile of two cysteine-rich AMPs from the hemolymph of the cattle tick Boophilus microplus. A 10,204 Da polypeptide, with six cysteine residues and no sequence similarity to any known molecule, was isolated from the cell-free hemolymph. Because of its sequence originality, this peptide was named microplusin. The second AMP was isolated from the hemocytes of B. microplus. This peptide, with a molecular mass of 4285 Da and six cysteines, is a defensin with similarity to the insect defensin family members. The cDNA cloning established that microplusin is synthesized as a prepeptide while the tick defensin is synthesized as a prepromolecule. Interestingly, despite the fact that microplusin and defensin have been isolated from different compartments, their gene expression was found to have similar tissue distribution.
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo 05508-900, Brazil.
authors.forename: Andréa C
authors.initials: AC
authors.lastname: Fogaça
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Lorenzini
authors.forename: Luciana M
authors.initials: LM
authors.lastname: Kaku
authors.forename: Eliane
authors.initials: E
authors.lastname: Esteves
authors.forename: Philippe
authors.initials: P
authors.lastname: Bulet
authors.forename: Sirlei
authors.initials: S
authors.lastname: Daffre
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000302:isolation & purification / Q000494:pharmacology; D002417:Cattle / Q000469:parasitology; D002851:Chromatography, High Pressure Liquid; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005216:Fat Body / Q000737:chemistry; D005260:Female; D015870:Gene Expression; D006434:Hemocytes / Q000737:chemistry; D006458:Hemolymph / Q000737:chemistry; D026863:Ixodidae / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D016982:Micrococcus luteus / Q000187:drug effects; D008969:Molecular Sequence Data; D010053:Ovary / Q000737:chemistry; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary