April 21, 2016
PBIO Seminar Series: Dwight Bergles
Dwight Bergles, Ph.D.
The Solomon H. Snyder Department of Neuroscience
Johns Hopkins University
Sounds in silence: How glial cells in the ear promote development of the auditory system.
Spontaneous electrical activity is a prevalent feature of the developing nervous system, which has been shown to influence the maturation and survival of neurons, as well as the refinement of circuits in the brain. In the auditory system, bursts of activity are initiated in the cochlea when ATP is released by supporting cells that lie adjacent to inner hair cells (IHCs). This periodic release of ATP induces inward currents, crenations (cell shrinkage), and Ca2+ waves in supporting cells, events that are associated with periodic depolarization of inner hair cells and subsequent bursts of action potentials in primary auditory neurons. This activity is prominent during the first two postnatal weeks in mice, prior to hearing onset, suggesting that it may influence development of the cochlea and maturation of central auditory circuits. In this lecture, I will describe how glial cells in the inner ear have adapted a pathway used for fluid secretion in other organs to induce excitation of hair cells, define several key molecular components of this pathway and show using in vivo imaging how these peripheral glial cells control neural activity in auditory centers of the CNS.
host: Ed Rubel