The survival of an organism depends on its ability to respond appropriately to environmental stimuli. In higher organisms, this response is mediated through the function of the nervous system. To maximize adaptability, the nervous system must not only distinguish between qualitatively different stimuli, but also their intensities. Two major properties allow the nervous system to achieve this goal. First, the nerve impulses produced by a given stimulus travel via a specific neuronal network. Second, the threshold and frequency of the nerve impulses generated by a given stimulus can be modified by external conditions. The information necessary for building both the neuronal network and its components for nervous impulse generation are encoded by the genome of the organism. One of the major intellectual challenges of modern biology is to understand how this genomic information is translated to an appropriate axonal network, and how those networks function to produce appropriate behavior. Genetic analysis of behavior is a powerful approach to these problems. It is typically carried out in three stages. First, a paradigm is designed in which the behavior of interest can be easily observed and scored in normal individuals. The second stage uses mutagenesis to identify mutant genes that show clear deviations in behavior. Third, modern genetic techniques make it possible to either shut down or activate specific regions of the nervous system, to identify the circuits within the neural network that produces the behavior. The purpose of this project is a genetic analysis and silencing of specific neuronal circuits to examine two behavioral paradigms, the Drosophila models of pain and fear, that the investigator's group has developed. Both of these involve basic neuronal elements, including sensors that detect the stimulus and neuronal networks that execute the behavior when the sensor is activated. Using Drosophila as a model organism, this research will increase the scientific understanding of the mechanisms that allow complex behaviors to be encoded by the genome,. The basic principles learned from these studies will provide a foundation for understanding the molecular and neural principles that underlie behavior in humans and other organisms. It is expected that students at a range of levels, from high school to graduate school, will participate in this research.
