K+ currents play a major role in membrane excitability. Repolarizing outward currents are carried out almost exclusively by K+ channel conductances and/or distributions of K+ channels may be modulated in order to generate excitable membrane diversity. Although much is known about K+ channel physiology and pharmacology, relatively little is known about its molecular basis. The present research uses electrophysiological and molecular genetic methods to examine K+ channels. The goal is to provide a molecular understanding of K+ channel structure and function. Experiments focus on the Shaker (Sh) gene complex in Drosophila that encodes K+ channels. We have previously cloned the chromosomal region containing Sh. In the present proposal we will continue to use molecular genetic methodologies to identify the DNA sequences which encode Sh. We will use nucleotide sequence methods to deduce the amino acid sequence of the channel encoded by Sh. Finally, we will examine methods that may be used to identify other K+ channel genes in Drosophila. Sh is one of the best-studied sets of nervous system genes. Physiological, genetic, and molecular genetic analyses of Sh provide basic research with important implication for any nervous system disease with a heritable component.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
2R01NS021327-04
Application #
3402360
Study Section
Genetics Study Section (GEN)
Project Start
1984-07-01
Project End
1990-06-30
Budget Start
1987-07-01
Budget End
1988-06-30
Support Year
4
Fiscal Year
1987
Total Cost
Indirect Cost
Name
California Institute of Technology
Department
Type
Schools of Arts and Sciences
DUNS #
078731668
City
Pasadena
State
CA
Country
United States
Zip Code
91125
Ramaswami, M; Tanouy, M; Mathew, M K (1994) Facile formation of heteromultimeric potassium channels by expression of cloned human cDNAs. Indian J Biochem Biophys 31:254-60
Tseng-Crank, J; Pollock, J A; Hayashi, I et al. (1991) Expression of ion channel genes in Drosophila. J Neurogenet 7:229-39
McCormack, K; Tanouye, M A; Iverson, L E et al. (1991) A role for hydrophobic residues in the voltage-dependent gating of Shaker K+ channels. Proc Natl Acad Sci U S A 88:2931-5
Tseng-Crank, J C; Tseng, G N; Schwartz, A et al. (1990) Molecular cloning and functional expression of a potassium channel cDNA isolated from a rat cardiac library. FEBS Lett 268:63-8
McCormack, K; Lin, J W; Iverson, L E et al. (1990) Shaker K+ channel subunits from heteromultimeric channels with novel functional properties. Biochem Biophys Res Commun 171:1361-71
Pollock, J D; Krempin, M; Rudy, B (1990) Differential effects of NGF, FGF, EGF, cAMP, and dexamethasone on neurite outgrowth and sodium channel expression in PC12 cells. J Neurosci 10:2626-37
Iverson, L E; Rudy, B (1990) The role of the divergent amino and carboxyl domains on the inactivation properties of potassium channels derived from the Shaker gene of Drosophila. J Neurosci 10:2903-16
Gautam, M; Tanouye, M A (1990) Alteration of potassium channel gating: molecular analysis of the Drosophila Sh5 mutation. Neuron 5:67-73
Ramaswami, M; Tanouye, M A (1989) Two sodium-channel genes in Drosophila: implications for channel diversity. Proc Natl Acad Sci U S A 86:2079-82
Kamb, A; Tseng-Crank, J; Tanouye, M A (1988) Multiple products of the Drosophila Shaker gene may contribute to potassium channel diversity. Neuron 1:421-30

Showing the most recent 10 out of 15 publications