Excitation of the sensory or hair cells of the inner ear begins by the mechano-transduction of an auditory or vestibular stimulus via the stereocilia located at the apex of these cells. These stimuli are modulated by various types of ionic currents found at the base and lateral sides of the sensory cells. The research in my laboratory is concerned with the mechanisms that regulate the development and function of the ion channels that underlie these currents. These proteins not only regulate sensory coding by the hair cells but they may also regulate survival and apoptosis during development. Our studies have revealed numerous genes that encode K+ ion channels found in both cochlear and vestibular hair cells, and in the ganglion cells that innervate these receptor cells. With these genes, we have begun to reveal different types of proteins that interact with specific K+ channels during the course of embryonic development. These protein-protein interactions are pertinent to regulating, not only ion channel expression, but also, their biophysical properties. These data are relevant to understanding how sensory systems are formed during development as well as providing insights into channelopathies that cause deafness and balance disorders. The techniques that we employ include gene cloning, expression of genes in heterologous systems such as CHO cells, yeast two-hybrid screening, immunoprecipitation, in situ hybridization, and whole cell tight-seal recording of both hair cells and CHO cells.