Submitted to: Peptides
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/2005
Publication Date: 11/1/2005
Citation: Nachman, R.J., Russell, W.K., Coast, G.M., Russell, D.H., Predel, R. 2005. Mass spectrometric assignment of Leu/Ile in neuropeptides from single neurohemal organ preparations of insects. Peptides. 26:2151-2156.
Interpretive Summary: Because of problems with the development of resistance to conventional pesticides, there is a critical need for new concepts and alternative approaches in controlling insect pests. The basic premise of this research is that neuropeptides (short chains of amino acids) serve as potent messengers in insects to regulate vital functions. New, selective control measures may be developed by designing metabolically stable mimics of these neuropeptides that actively inhibit or over-stimulate functions regulated by them, resulting in disruption of the internal environment of the insect. We report on the use of state-of-the-art analytical techniques to unambiguously characterize the structure of regulatory neuropeptides via direct analysis of a single organ within two species of fly, including the housefly. The housefly is a pest of man, poultry and confined livestock. A deeper understanding of the specific structures of neuropeptides, where they are stored and released, and how these neuropeptides regulate critical processes in insects will aid in the design of strategies to disrupt feeding and survival. The work brings us one step closer to the development of practical neuropeptide-like substances that will be effective in controlling pest insects in an environmentally friendly fashion.
Technical Abstract: MALDI-TOF-TOF tandem mass spectrometry has been applied for the first time on an insect target, and peptidomic analysis of a single abdominal dorsal ganglionic sheath preparation allows the unambiguous assignment of internal Leu/Ile positions of CAP2b/PVK neuropeptides in the housefly Musca domestica and flesh fly Neobellieria bullata. Previous mass spectrometric techniques could not distinguish between these two amino acid isomers. This powerful technique can greatly accelerate the pace of cataloguing the peptidomes of related species for systematic/taxonomic purposes and of the identification of specific sequences of insect neuropeptides that are implicated in the regulation of critical physiological processes.