|DE LOOF, A|
Submitted to: Peptides
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/19/2000
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, and an inability to penetrate the outer surface 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. In this paper, a review of newly discovered functions of neuropeptides that regulate muscles involved in the digestive and reproductive systems of insects is presented. Among these newly discovered functions include regulation of inhibition of food intake, of ovarian maturation, and of cuticle pigmentation. These functions are often critical to insect to insect survival, and therefore increase the likelihood that mimics of these neuropeptides can serve as disruptive agents in pest insects. The work reviewed here leads us one step closer to the development of practical neuropeptide-like agents that will be effective in controlling certain pests in an environmentally friendly fashion.
Technical Abstract: The field of neuropeptide research in insects during the past twenty years can be characterized by the enormous number of peptides that have been identified. In the locusts, Locusta migratoria and Schistocerca gregaria only, structural information is now available for more than 60 peptides. Quite a number of these peptides were isolated on the basis of their effect on visceral muscle contractions in vitro. A very limited number of reports describe the "in vivo" function of a myotropic neuropeptide. Moreover, for most of the brain neuropeptides, we ignore whether they have a hormonal function. In this paper, we describe the recently discovered in vivo effects of some of the myotropic peptides, identified in locusts in the past decade. Schistocerca-neuropeptide F accelerates egg development; locustasulfakinin inhibits food intake and [His7]-corazonin induces body color pigmentation.