Submitted to: Archives of Insect Biochemistry and Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 28, 1996
Publication Date: N/A
Interpretive Summary: The gypsy moth is a major pest of American forests and residential landscapes. Not only does this insect damage the leaves of trees, but infestation of a tree may result in its death. It is important to develop a specific, environmentally- safe means of insect control without the use of toxic chemicals. One possible mechanism is to prevent reproduction of these insects, as the immature stages are the most devastating to trees. We have isolated and purified a peptide from the brain of the gypsy moth which controls ecdysone production in the testes of larval and pupal stages. This ecdysone is one of the biochemicals found in the insect which controls development of the testes. Identification of this peptide and information about the way in which it works will enable scientists to develop compounds to interfere with its production or its effectiveness. If development of the testes is prevented, male insects will be sterile and will not be able to produce offspring. This would prevent large numbers of immature insects from colonizing in trees and would prevent large-scale losses for producers of wood products, as well as losses to homeowners and public parks, due to infestation by gypsy moths.
Technical Abstract: A peptide was isolated from brains of the gypsy moth, Lymantria dispar, which was able to stimulate synthesis of ecdysone in the testes of larval and pupal insects. This ecdysiotropic peptide was purified and the structure determined to be NH2-Ile-Ser-Asp- Phe-Asp-Glu-Tyr-Glu-Pro-Leu-Asn-Asp-Ala-Asp-Asn-Glu-Val-Leu-Asp- Phe-OH by protein sequence analysis and electrospray mass spectrometry. The peptide was bi-phasic in activity, with maximal activity in the larval testes at 10**-13 M and 10**-10 M, with a minimum at 10**-11 M, and with maxima at 10**-14 M and 10**-9 M and minimum at 10**-11 M for pupal testes