9506166 Rankin Insects have been widely used as model systems to study basic mechanisms of hormone production and action. Moreover, study of the regulation of hormone production in insects by key regulatory proteins holds promise in the development of biorational pesticides. The general objective of Dr. Rankin's proposal is to understand the hormonal bases of insect mating, egg development and subsequent maternal behavior that lead to reproductive success in an insect. This investigation will utilize the ring-legged earwig, Euborellia annulipes. This insect has proven to be an excellent, inexpensive model system for investigating the hormonal regulation of egg development and reproductive behavior because it exhibits precisely timed cycles of egg development followed by maternal behavior which are correlated with specific hormone production. The specific goals are to investigate: 1) regulation of juvenile hormone production by alterations of levels two insect hormones (juvenile hormone and ecdysone), diet and mating status and by surgical removal of ovaries; 2) whether proteins that inhibit reproduction (allatostatins), similar to those in cockroaches, occur in the earwig by using existing antibody probes for determination of amounts and sources of such proteins; and 3) whether the cockroach allatostatins can inhibit cockroach hormone synthesis. Each of these manipulations will be assessed for their effects on (or correlations with) two fundamental reproductive behaviors: mating and maternal care. The results are expected to increase understanding of the physiological regulation of key reproductive hormones, egg development, and behaviors that contribute to the reproductive process in an insect. ***
