title: Variation in the salivary peptide, maxadilan, from species in the Lutzomyia longipalpis complex.
abstract: Maxadilan is an approximately 7kDa peptide that occurs in the saliva of the sand fly Lutzomyia longipalpis. This peptide is a potent vasodilator and may also have immunomodulatory effects related to the pathogenesis of leishmanial infections. Variation in the primary DNA and inferred amino acid sequence of maxadilan is reported. Differences were found within and among natural field populations as well as among sibling species. Extensive amino acid sequence differentiation, up to 23%, was observed among maxadilan from different populations. This is a remarkable degree of polymorphism considering the small size of this peptide. The vasodilatory activity of maxadilan was equivalent among recombinant maxadilan variants. All maxadilan variants induce interleukin-6. Predicted secondary structure and hydrophobicity plots suggest that these characteristics are conserved among variant peptides. However, profiles based on the antigenic index do differ among peptides.
authors.affiliation: Department of Pathology & Center for Tropical Diseases, University of Texas Medical Branch, Galveston 77555-0609, USA. glanzaro@utmb.edu
authors.forename: G C
authors.initials: GC
authors.lastname: Lanzaro
authors.forename: A H
authors.initials: AH
authors.lastname: Lopes
authors.forename: J M
authors.initials: JM
authors.lastname: Ribeiro
authors.forename: C B
authors.initials: CB
authors.lastname: Shoemaker
authors.forename: A
authors.initials: A
authors.lastname: Warburg
authors.forename: M
authors.initials: M
authors.lastname: Soares
authors.forename: R G
authors.initials: RG
authors.lastname: Titus
mesh_terms: D000818:Animals; D001483:Base Sequence; D004247:DNA; D019476:Insect Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000494:pharmacology*; D015850:Interleukin-6 / Q000096:biosynthesis; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D011576:Psychodidae; D011817:Rabbits; D012471:Salivary Proteins and Peptides / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000737:chemistry / Q000145:classification / Q000494:pharmacology*
chemical_list: D019476:Insect Proteins; D015850:Interleukin-6; D012471:Salivary Proteins and Peptides; D014665:Vasodilator Agents; C069147:maxadilan protein, insect; D004247:DNA