The goal of research in this laboratory is to understand the biochemical and molecular neurobiology of sensory transduction in the developing and adult auditory system. Specifically, research in the Neurochemistry Laboratory, under the direction of Dr. Barbara J. Morley, is concerned with the role of neurotransmitters and receptors in the establishment of neural pathways and the formation of maintenance of synaptic connections. Experiments currently in progress include the pharmacological and immunocytochemical characterization of neurotransmitter receptor subunits and assembled receptors, and the expression of subunits of the receptors using in situ hybridization and real time RT-PCR. In addition, mice with gene deletions are used as tool for understanding the function of certain receptor subunits and compensation for gene loss by the up-regulation of other genes and proteins.
The laboratory has about 1,100 sq. feet of space; divided into a main laboratory room, cell culture facility, and an imaging facility. The laboratory is equipped for biochemical and molecular biology application with facilities for real-time RT-PCR, PCR for genotyping, in situ hybridization, radioligand autoradiography, image analysis, cell culture, and radioimmunoassays.
The major equipment includes, GeneQuant II, Applied Biosystems ABI 7000 sequence detection system, Perkin Elmer PCR, Reichert 2800E cryostat, MCID Image Analysis System (Imaging Research, Inc.); Packard phosphoimager; Sensicam and Optronics DEI-75 video cameras, Leica DMLB fluorescence microscope interfaced with and controlled by a PC with ImagePro and Vaytek digital confocal software, Leitz inverted fluorescence microscope, a Zeiss stereomicroscope, and high-speed centrifuges.
Summary of Research Program
For Clinicians and Scientists
The current focus of this research program is to develop a better understanding of fundamental aspects of sensory transduction in the periphery (cochlea) and central auditory brainstem. The techniques used identify, isolate, and characterize genes and proteins that are relevant during different stages of development. Some of the genes and proteins have age-dependent functions that differ throughout the lifespan. The results of our studies are critical for understanding the normal progression of synapse formation during development and the maintenance of proper connections in the normal cochlea and brain. Understanding the normal auditory system is critical for evaluating the effects of injury and damage. It is necessary to understand the normal ear before constructing gene therapies and biochemical intervention strategies to reinstate normal hearing in damaged ears. This research has been funded by NIH, the Deafness Research Foundation, the National Organization for Hearing Research, and the State of Nebraska.
The research in the Neurochemistry Laboratory is focused on understanding how and why certain chemicals in the ear and brain are expressed in development and in the adult. Different chemicals have differing function, depending on age. It is critically important to understand the chemical organization at different ages because chemical and environmental substances can affect hearing in a greater or different way than they would affect the adult. In addition, it is important to know how the normal ear works before attempting to use treatment strategies, such as drugs, implants, or novel cell transplants or gene therapy.
Specific Areas of Research:
- Understanding the role of acetylcholine and acetylcholinesterase in the development and maturation of the primary neurotransmitters in the auditory brainstem.
- Understanding how acetylcholine drives the auditory system before the onset of hearing.
- Understanding how the nicotinic acetylcholine receptors function in the outer hair cells and spiral ganglion cells of the cochlea.
- Construction of mice and cell lines that are have null mutations for cochlea-specific genes.