Dwight E. Bergles, Ph.D.

The Research

Johns Hopkins University

Connexin involvement in spontaneous activity in the developing cochlea

Our recent studies indicate that spontaneous activity in the developing auditory nerve is initiated by the release of ATP from supporting cells in the organ of Corti. The goal of these studies is to evaluate the role of connexins in triggering ATP release from supporting cells. We propose to use electrophysiological and imaging methods in whole-mount preparations of pre-hearing cochleas to probe the sensitivity of spontaneous activity to manipulations that inhibit gap junction/hemichannel activity. We will extend these studies by testing whether expression of connexin 26 mutants associated with congenital hearing loss (R75W, W44C) alters this spontaneous activity. The studies outlined in this proposal seek to test the hypothesis that connexins play an essential role in the propagation of Ca2+ waves through the support cell network, and are responsible for the release of ATP in the developing organ of Corti.