The objective is to define the molecular events in the signal transduction by which the ciliated protozoan paramecium tetraurelia responds to stimuli by changing its swimming speed and direction. These events include regulation of ion channels and regulation of the ciliary axoneme's motility. Paramecium combines the experimental advantages of a microbe (genetics and biochemistry) with the advantages of a large size (electrophysiology and microinjection). Ca and cyclic nucleotides modulate changes in ciliary beta frequency and stroke orientation. Many of the proteins (Ca channels, calmodulin, calmodulin-binding proteins, adenylate cyclase, protein kinases, phosphatases, dyneins) essential to this process are localized in the cilium. Some of these proteins have already been purified from Paramecium; others are currently being purified. Antibodies (polyclonal and monoclonal) against purified proteins will be used to test definitively whether a given protein functions in the sensory pathway. Methods will be developed for adding antibodies to living cells by microinjection, electroporation or reversible permeabilization. The effects of each antibody on the swimming speed and direction will be assessed. Monoclonal antibodies raised against semi-purified fractions (e.g., minor proteins of ciliary membrane which should include the Ca channel proteins) will be screened for their effects on the swimming behavior of paramecia. Any antibodies that show behavioral effects will be assayed electrophysiologically (in collaboration with Ching Kung's laboratory) to determine which, if any, of the ion conductance mechanisms known to function in sensory transduction is affected by each. Antibodies found to alter electrical properties of the membrane in voltage-clamp studies in whole cells will be characterized further by studying single channels in isolated patch-clamped surface membrane. These studies may lead to the identification of proteins that form ion channels or regulate their activities. To study the targets of protein phosphorylation, specific proteins will be immunoprecipitated from detergent extracts of quick-killed cells, and their states of phosphorylation will be compared in cells stimulated to swim fast or backwards, or in wild type and mutant cells. Antibodies will also be used to screen behavioral mutants for enzymic differences, and to screen expression libraries of Paramecium DNA in E. coli.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM032514-06A1
Application #
3281423
Study Section
Cellular Biology and Physiology Subcommittee 1 (CBY)
Project Start
1983-07-01
Project End
1994-03-31
Budget Start
1989-04-01
Budget End
1990-03-31
Support Year
6
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Wisconsin Madison
Department
Type
Earth Sciences/Resources
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Hochstrasser, M; Carlson, G L; Walczak, C E et al. (1996) Paramecium has two regulatory subunits of cyclic AMP-dependent protein kinase, one unique to cilia. J Eukaryot Microbiol 43:356-62
Carlson, G L; Nelson, D L (1995) Isolation and characterization of protein kinases from Paramecium cilia. Methods Cell Biol 47:473-80
Son, M; Gundersen, R E; Nelson, D L (1993) A second member of the novel Ca(2+)-dependent protein kinase family from Paramecium tetraurelia. Purification and characterization. J Biol Chem 268:5940-8
Clark, K D; Hennessey, T M; Nelson, D L (1993) External GTP alters the motility and elicits an oscillating membrane depolarization in Paramecium tetraurelia. Proc Natl Acad Sci U S A 90:3782-6
Walczak, C E; Marchese-Ragona, S P; Nelson, D L (1993) Immunological comparison of 22S, 19S, and 12S dyneins from Paramecium cilia. Cell Motil Cytoskeleton 24:17-28
Shih, S J; Nelson, D L (1992) Proteolytic processing of secretory proteins in Paramecium: immunological and biochemical characterization of the precursors of trichocyst matrix proteins. J Cell Sci 103 ( Pt 2):349-61
Clark, K D; Nelson, D L (1991) An automated assay for quantifying the swimming behavior of Paramecium and its use to study cation responses. Cell Motil Cytoskeleton 19:91-8
Bonini, N M; Evans, T C; Miglietta, L A et al. (1991) The regulation of ciliary motility in Paramecium by Ca2+ and cyclic nucleotides. Adv Second Messenger Phosphoprotein Res 23:227-72
Peterson, J B (1991) Small GTP-binding proteins associated with secretory vesicles of Paramecium. J Protozool 38:495-501
Bonini, N M; Nelson, D L (1990) Phosphoproteins associated with cyclic nucleotide stimulation of ciliary motility in Paramecium. J Cell Sci 95 ( Pt 2):219-30

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