|Dr. Bruce Yazejian, Assistant Professor, Biological Sciences|
|B.S., Michigan State University, Biochemistry|
Ph.D., University of Southern California, Biology (Neurobiology)
Genetic Control of Sensory Hair Cell Membrane Channels in Zebrafish
Hearing and balance deficits are among the most common inherited sensory disorders. An understanding of the genes that control the function of auditory and vestibular structures will be critical to the development of therapies that address these insufficiencies.
Sensory neurons in the ears of vertebrates--called hair cells--detect and transduce sound, gravitational and vibrational stimuli from the environment into electrical signals. (These cells make it possible for us to enjoy both iPods and rollercoasters.) Once activated, hair cells pass information to higher order neurons in the brain by releasing chemical neurotransmitters at synapses. The long term goal of the research in my lab is directed at understanding how the genome specifies the instructions that control the release of neurotransmitters from hair cells. Current projects involve studying isolated wild type and mutant hair cells from zebrafish using electrophysiological methods to characterize the membrane channels and receptors that mediate transmitter release. It is hoped that through this work a clearer understanding of the roles sensory hair cells play in mediating hearing and balance in vertebrates will emerge.
Recently Taught Courses
- Sun, X. P., Yazejian, B., and Grinnell, A.D. (2004). Electrophysiological properties of BK channels in Xenopus motor nerve terminals. Journal of Physiology 557: 207-228.
- Grinnell, A.D., Yazejian, B., Sun, X.P, and Chen, B-M (2003). Ca2+ dynamics at nerve-terminal active zones monitored by endogenous KCa channels. In: Epithelia, Pumps, Transporters and Ion Channels: Structure and Function, Eds. F. Bezanilla and F. Sepulveda, Plenum Press, N.Y
- Pattillo, J.M., Yazejian, B., DiGregorio, D., Vergara, J.L., Grinnell, A.D. and Meriney, S.D. (2001). Contribution of presynaptic calcium-activated potassium currents to transmitter release regulation in cultured Xenopus nerve-muscle synapses. Neuroscience 102: 229-240.
- Yazejian, B., Sun, X..-P. and Grinnell, A.D. (2000). Tracking Ca2+ dynamics during neurotransmission with Ca2+-activated K channels. Nature Neuroscience, 3: 566-571.
- Yazejian, B., DiGregorio, D., Vergara, J.L., Poage, R., Meriney, S.D. and Grinnell, A.D. (1997). Direct measurements of calcium and calcium-activated potassium currents regulating neurotransmitter release at Xenopus neuromuscular junctions. Journal of Neuroscience, 17:2990-3001.
- Yazejian, B. and Fain, G.L. (1993). Whole-cell currents activated at nicotinic acetylcholine receptors on ganglion cells isolated from goldfish retina. Visual Neuroscience 10:353-361.
- Yazejian, B. and Fain, G.L. (1992). Excitatory amino acid receptors on isolated retinal ganglion cells from the goldfish. Journal of Neurophysiology 67:94-107.