Chemosensory receptor cells detect molecules and ions in the environment as a signal different from the background. There are two fundamental problems olfactory systems face. First, when the environment changes rapidly, how does the chemosensory system avoid breakdown in its detecting capability? Second, how do olfactory membranes that detect these chemicals function over time when the membranes themselves are constantly renewed? This project uses the antennae of an intertidal crab as a novel model system to investigate both of these important questions, using a combination of physiological and microscopic techniques. Experiments are designed to determine how ion levels are regulated in the fluid bathing the chemosensory membranes to maintain suitable conditions for olfactory function. Morphological studies will define how these membranes react by growth or regeneration to the challenge of exposure to very different salinities. The environmental change can range between seawater and freshwater in the tidal estuaries in which these crabs live, and this study helps to understand how the chemosensory system can adapt to those rapid changes. Results will be important beyond chemosensory neuroscience alone, for understanding the maintenance of sensory membranes in general, for cell biology by understanding membrane turnover and regeneration, and for ecology by understanding some of the biological mechanisms useful for animals to adapt to rapid environmental change.
