Variation in the salivary peptide, maxadilan, from species in the Lutzomyia longipalpis complex

• Published in: Insect molecular biology Vol. 8; no. 2; pp. 267 - 275
• Main Authors: Field, L. M., James, A. A., Lanzaro, G. C., Lopes, A. H. C. S., Ribeiro, J. M. C., Shoemaker, C. B., Warburg, A., Soares, M., Titus, R. G.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.05.1999
• Subjects: Animals; Base Sequence; DNA; Insect Proteins - chemistry; Insect Proteins - classification; Insect Proteins - genetics; Insect Proteins - pharmacology; Interleukin-6 - biosynthesis; Lutzomyia longipalpis; Macrophages, Peritoneal - drug effects; Macrophages, Peritoneal - metabolism; maxadilan; Molecular Sequence Data; population genetics; Protein Structure, Secondary; Psychodidae; Rabbits; saliva; Salivary Proteins and Peptides - chemistry; Salivary Proteins and Peptides - classification; Salivary Proteins and Peptides - genetics; Salivary Proteins and Peptides - pharmacology; vasodilator; Vasodilator Agents - chemistry; Vasodilator Agents - classification; Vasodilator Agents - pharmacology
• ISSN: 0962-1075; 1365-2583
• DOI: 10.1046/j.1365-2583.1999.820267.x

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.