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The zebrafish has emerged as a powerful model organism over the last two decades due to its closer evolutionary relationship to humans than invertebrates, easy maintenance, and high fecundity. These qualities of zebrafish have been exploited in this project to address two main questions. First, to localize supervillin in zebrafish hair cells. Hair cells are responsible for hearing and balance in zebrafish as well as humans. Actin is a cytoskeletal protein, which along with actin-associating proteins, provides the structural framework for stereocilia and the cuticular plate in the hair cells. The cuticular plate provides a strong foundation for stereocilia but is poorly understood in terms of protein composition and its development. Supervillin is one of the actin-associating proteins. In this study, we examined zebrafish hair cells using immunofluorescence assay to localize supervillin. We have demonstrated that supervillin localized specifically to the hair cell cuticular plate in the transgenic lines of zebrafish, which can be indicative of its role in shaping and maintaining the integrity of this mysterious organelle.In the second study, the transgenic HGn39D zebrafish line is used to design a small molecule screen to test the effects of the chemicals on the lateral line afferent neurons. Afferent innervation in the lateral line of the zebrafish serves a model for peripheral nervous system and this preliminary screen can help in identifying the chemicals that can be used to address problems such as peripheral nerve damage. The HGn39D fish express GFP in the afferent neurons of the lateral line system, including anterior lateral line (ALL) and posterior lateral line (PLL) ganglia. Migration of growth cones of afferent neurons start around 24 hpf, and we used this time point to dechorionate the embryos and subject them to 1,040 different small molecules from a chemical library. A small molecule that altered the phenotype of the HGn39D zebrafish was considered a `hit’. A total of 63 `hits’ were confirmed after rounds of phenotypic screening. These `hits’ were grouped into 12 broad categories, based on the phenotype displayed, which ranged from almost no afferent neuronal development to hair cell-like structures on the dendritic arbors. Studies leading to the identification of the mechanism of action of the `hits’ that exhibit a particular phenotype might also help in better understanding of sensory processing of lateral line system in zebrafish and its implication with respect to hearing research.