The application presents two focused specific aims related to establishing the role of Eph-like receptors and their associated ligands in the development and maintenance of the statoacoustic ganglion. The first is to identify the cell-type specific pattern of expression of Eph-like receptors and ligands in otocysts and the statoacoustic ganglion. The second is to test the ability of the Eph- like molecules to promote outgrowth or survival of the statoacoustic ganglion cells in culture. Eph-like molecules form the largest known family of receptor tyrosine kinases, and, based on their presence on cells and nerve fibers of the statoacoustic ganglion and on cells within the sensory epithelia of the otocysts, it has been hypothesized that they play a role in regulating nerve/hair cell interactions at very early stages of development. The experiments use in situ hybridization and Northern blotting experiments to localize and quantitate mRNA, and use immunoglobulin tagged Eph-like ligands and receptors to immunolocalize and quantitate proteins. Culture conditions will be used for assaying the effects of endogenously supplied Eph-like molecules. The experiments proposed in this application will form the groundwork for future studies on the inner ear under conditions where there are genetically or environmentally induced auditory and vestibular deficits.
| Medd, A M; Bianchi, L M (2000) Analysis of BDNF production in the aging gerbil cochlea. Exp Neurol 162:390-3 |
| Cowan, C A; Yokoyama, N; Bianchi, L M et al. (2000) EphB2 guides axons at the midline and is necessary for normal vestibular function. Neuron 26:417-30 |
| Bianchi, L M; Liu, H (1999) Comparison of ephrin-A ligand and EphA receptor distribution in the developing inner ear. Anat Rec 254:127-34 |
| Bianchi, L M; Liu, H; Krug, E L et al. (1999) Selective and transient expression of a native chondroitin sulfate epitope in Deiters' cells, pillar cells, and the developing tectorial membrane. Anat Rec 256:64-71 |
| Bianchi, L M; Gale, N W (1998) Distribution of Eph-related molecules in the developing and mature cochlea. Hear Res 117:161-72 |
