The goal of the laboratory is to identify cell-cell interactions during sensory organ formation using zebrafish. As an experimental system, the lateral line of the zebrafish was chosen based on (1) the accessibility of the sensory organs to direct observation and manipulation; (2) the similarity between lateral line hair cells and hair cells in the inner ear; and (3) the genetic tools available in zebrafish to identify genes involved in sensory organ formation. So far, 20 mutants affecting different aspects of lateral line development have been identified. Several mutants are particularly interesting because they possess 'extra' sensory organs on their trunk, and lack glia along the posterior lateral line nerve. Historically, glial cells have been thought to be merely support cells for neurons, but recent studies have shown that glia play a much more important role in nervous system development. Analyses of one of these mutants allowed the PI to make a fundamentally new observation relevant to glia-neuron interactions: the identification of a key role for glia in controlling hair cell differentiation. The goals of this study are to reinvestigate normal lateral line development and to characterize the other lateral line mutants that possess extra neuromasts (sensory organs) to determine how glia and neurons interact in sensory organ formation. Results from these experiments are likely to reveal genetic interactions important for sensory organ formation. The genetic interactions discovered in the zebrafish lateral line are very likely to be applicable to basic developmental processes involved in the formation of other organs, in zebrafish as well as in other vertebrates. This project involves training opportunities for graduate and undergraduate students. The systematic analyses of the cell labeling experiments will be a good entry point for novice researchers to learn how to design, perform and critically evaluate experiments. Thus, it is expected that students will be able to generate data of sufficient significance to merit presentations of their work in seminars, conferences, and publications.
