Development of the zebrafish lateral line sensory system

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I am interested in understanding how behaviourally relevant neural circuits are assembled during embryonic development.  We study the rapidly developing zebrafish embryo as it allows us to combine innovative approaches to characterize the formation of simple neural circuits in the vertebrate nervous system.  For example, in previous groundbreaking work funded by the NSERC, with a PhD student we pioneered electrophysiological methodologies in zebrafish and used these to follow the embryonic response to tactile stimuli from sensory inputs to interneuron integration to motor output.  In combination with genetic and cell biological approaches, we discovered the coordinating role of the hindbrain in spinal cord circuit development, a fundamental new principle in developmental biology.  ***    We observed with the same PhD student that a sensory mutation of zebrafish, with an MSc student a gene underlying a sensory neuropathy and with a visiting professor that a gene related to more general disorders all affect progenitor migration and/or differentiation during development of the zebrafish lateral line, a sensory system that is conserved in fishes and is an evolutionary precursor of the inner ear basilar membrane. We now propose to extend this creative program using a combination of genetic loss- and gain-of-function approaches to define the developmental mechanism for this sensory system, which will further impact our knowledge of developmental neurobiology. ***     The zebrafish lateral line is an insightful system for studies of cellular development.  The lateral line is comprised of a series of peripheral neuromasts along the trunk.  In zebrafish, the neuromasts contain only two cell types: neural hair cells and non-neural supporting cells.  The lateral line develops from a neuromast primordial, a cluster of a hundred cells generated in the head and which migrates towards the tail, depositing along the way clusters of about 20 progenitor cells generating sensory neurons with axons tethered to their point of exit from the head, forming the future lateral line nerve. The availability of transgenic and mutant lines or manipulations provide unique inroads to further study zebrafish lateral line development.  Based on previous genetic discoveries in my lab, our program will characterize the genes regulating primordium migration and the subsequent generation of neuromast hair and support cells, two fundamental aspects of lateral line development of broad interest.****** **