Collaborative Research: Perception of the Steroid Molting Hormone, 20-Hydroxyecdysone (20-HE) and its Role in Orchestrating Aggressive Interactions in the American Lobster.

Assumption College, Worcester MA

Investigators

Abstract

Perception of the Steroid Molting Hormone, 20-Hydroxyecdysone (20-HE) and its Role in Orchestrating Aggressive Interactions in the American Lobster. The purpose of this research is to identify and analyze the role of steroid hormones in aggressive behavior. The study will investigate how the perception of the steroid molting hormone affects aggression in a model animal, the American lobster. Aggression is a vital component of the survival strategies of all animals and is used in the acquisition of food, mates, and territory. The research will contribute significantly to the understanding of how steroid hormones modulate aggressive behavior. We expect to show that steroids not only alter the internal aggressive state of an animal, but are also used as signaling tools to modify the behavior of an opponent in an aggressive interaction. A primary goal of the project is to give undergraduates an intensive research experience in up-to-date methods of neurobiology. The project is a collaboration between Kass-Simon at the University of Rhode Island, and Cromarty at Assumption College. It will involve URI graduate students, Assumption College undergraduates, and under-represented minority undergraduates from the New England Board of Higher Education's Excellence Through Diversity Initiative Program. The following questions will be addressed: 1. Does smelling the steroid molting hormone affect fighting behavior? These are behavioral experiments in which lobsters deprived of their sense of smell fight animals who are exposed to steroids (or placebos). The experiments stem from earlier work showing that injected steroids increase lobster aggressiveness. 2. Are there molt-related differences in the receptor-responses to the molting hormone? These are electrophysiological experiments designed to show how olfactory cells respond electrically to the molting hormone as lobsters go from their hard-shelled (aggressive) to soft-shelled (timid) states. 3. Where are the molting hormone receptors located? These are microscopy experiments, in which fluorescent antibodies are used to locate the steroid receptors on the olfactory nerves. The experiments will augment the electrophysiology experiments.