|Tobe, S - UNIVERSITY OF TORONTO|
|Garside, C - UNIVERSITY OF TORONTO|
|Bowser, P R - UNIVERSITY OF TORONTO|
|Bendena, W - QUEEN'S UNIVERSITY|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: October 19, 1999
Publication Date: N/A
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 such pests. The basic premise of this research is that peptides (short chains of amino acids) serve as potent internal messengers in insects to regulate vital functions. Peptides themselves are unsuitable for control measures due to their instability to enzymes in the circulatory and digestive systems of the insect. 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. This paper reviews what is known about the multiple functions, mechanism of action, and progress in the development of mimetic analogs of the 'allatostatin' neurpopeptides. This work suggests that this class of neuropeptides can modulate aspects of digestion and development, and that mimics designed to resist the inactivation by natural forces that degrade the natural neuropeptides could disrupt these critical processes in pest insects. This work leads us one step closer to the development of practical neuropeptide-like chemicals that will be effective in controlling certain pest insects in an environmentally friendly fashion.
Technical Abstract: Aliatostatins are a multiftinctional family of peptides found across the Arthropoda. Information on the degradative pathway for these peptides has provided a strategy for the development of peptidomimetic analogues that are resistant to degradation but continue to show biological activity. They have been isolated from the midgut of cockroaches. Dip-AST 7 modulates the activity of carbohydrate-metabolizing enzymes present in the lumen of the midgut, indicating that allatostatins have functional roles in midgut beyond their ability to modulate muscle contraction. As well, a putative receptor for allatostatins in the midgut has been characterized using a competitive binding assay. The allatostatin gene, comprising 13 or 14 discrete putative peptides, is probably derived from internal gene duplication of an ancestral allatostatin DNA sequence. This raises questions as to the functional significance of this peptide family across the Arthropoda.