9631008 Ram The zebra mussel is a bivalve that was recently introduced accidentally into North America. It has been considered a biological pest and has drastic environmental impacts on water and power utilities and also an enormous negative impact on biodiversity, particularly with respect to native bivalves. However, because of its prolific reproductive capabilities (which are part of the reason it is a problem), the zebra mussel has also proven to be a highly suitable organism for studying the regulation of reproductive behavior. Many of the basic mechanisms regulating maturation of eggs prior to fertilization in bivalves are similar to those in our own bodies, yet these mechanisms are only now beginning to be understood at the molecular level. This project will investigate the mechanisms by which the neurochemical serotonin (a chemical also found in human nervous systems) regulates reproductive behavior and oocyte maturation. The specific aims of the project will be to determine the structure(s) of serotonin receptors in zebra mussels and to begin characterizing their coupling to cellular mechanisms through G-proteins. Zebra mussel serotonin receptors will be cloned and sequenced; their responses to serotonin and related drugs will be characterized; and their location will be determined. Binding and responses of cloned receptors to serotonin will be compared to effects of serotonin and related compounds on reproductive behavior of the mussels. This project will have significance for understanding reproductive mechanisms, for understanding serotonin mechanisms in general, and, in the long run, it may also have an impact on investigations of new ways to control zebra mussels.
