The major goal of the proposed research is to define,for amino acid taste reception, the molecular mechanisms that link stimulus-receptor interaction with subsequent ionic events in the receptor cells. Research will focus on the study of taste transduction in two model systems: catfish (L-Arg) and mice (MSG). Voltage-dependent and stimulus-regulated changes in membrane conductance will be examined in isolated receptor cells using whole-cell recording techniques and stimulus-induced changes in intracellular calcium levels will be monitored in real time using fura-2 and video microscopy. Single-channel properties will be studied in excised patches and planar bilayers into which taste membrane fragments have been incorporated. L-Arg and MSG receptors, that the investigator hopes will be cloned by another investigator, will be functionally expressed in heterologous systems and compared with native receptors in terms of specificity, sensitivity, ion selectivity, channel kinetics and pharmacology. It is hoped that these experiments will provide a comprehensive description of amino acid taste signal transduction in the catfish model, as well as the basis for similar studies in mammalian taste cells.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC001838-05
Application #
2608275
Study Section
Special Emphasis Panel (ZRG1-HAR (01))
Project Start
1992-12-01
Project End
2000-11-30
Budget Start
1997-12-01
Budget End
1998-11-30
Support Year
5
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Monell Chemical Senses Center
Department
Type
DUNS #
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Grosvenor, William; Kaulin, Yuri; Spielman, Andrew I et al. (2004) Biochemical enrichment and biophysical characterization of a taste receptor for L-arginine from the catfish, Ictalurus puntatus. BMC Neurosci 5:25
Kang, J; Teeter, J H; Brazier, S P et al. (2001) Molecular cloning and functional characterization of a novel delayed rectifier potassium channel from channel catfish (Ictalurus punctatus): expression in taste buds. J Neurochem 76:1465-74
Grosvenor, W; Feigin, A M; Spielman, A I et al. (1998) The arginine taste receptor. Physiology, biochemistry, and immunohistochemistry. Ann N Y Acad Sci 855:134-42
Kumazawa, T; Brand, J G; Teeter, J H (1998) Amino acid-activated channels in the catfish taste system. Biophys J 75:2757-66
Kaulin, Y A; Schagina, L V; Bezrukov, S M et al. (1998) Cluster organization of ion channels formed by the antibiotic syringomycin E in bilayer lipid membranes. Biophys J 74:2918-25
Feigin, A M; Schagina, L V; Takemoto, J Y et al. (1997) The effect of sterols on the sensitivity of membranes to the channel-forming antifungal antibiotic, syringomycin E. Biochim Biophys Acta 1324:102-10
Feigin, A M; Takemoto, J Y; Wangspa, R et al. (1996) Properties of voltage-gated ion channels formed by syringomycin E in planar lipid bilayers. J Membr Biol 149:41-7
Hayashi, Y; Zviman, M M; Brand, J G et al. (1996) Measurement of membrane potential and [Ca2+]i in cell ensembles: application to the study of glutamate taste in mice. Biophys J 71:1057-70
Caprio, J; Brand, J G; Teeter, J H et al. (1993) The taste system of the channel catfish: from biophysics to behavior. Trends Neurosci 16:192-7