The acidification of clathrin-coated vesicles from bovine brain has been shown to be mediated by a proton translocating ATPase which operates in parallel with a chloride transporter. A similar system has been identified in vesicles prepared from bovine renal medulla. The purification and reconstitution of the proton pump and chloride transporter from renal medulla is the central aim of this proposal; attempts at achieving this will be modeled after similar experiments performed with the clathrin-coated vesicle acidification system. Such a degree of resolution will allow for definition of any possible subunits and will provide a pure system with which to examine the stoichiometry and potential reversibility of the proton pump. With reconstitution of the chloride transporter, patch clamping of the proteoliposome will be performed to determine if the chloride transporter is a channel conductance. Moreover, with coreconstitution of the proton pump and chloride transporter, the precise interrelationship of these proteins will be determined. Characterization of the effects of mineralocorticoids on the proton pump and chloride transporter from rabbit renal medulla vesicles will be expanded. Any potential modulators of the rabbit vesicular acidification system will be tested with the reconstituted bovine kidney proton pump and chloride transporter to define function in a purified system.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases (NIADDK)
Type
Research Project (R01)
Project #
5R01AM033627-02
Application #
3152878
Study Section
Physiology Study Section (PHY)
Project Start
1984-07-01
Project End
1987-06-30
Budget Start
1985-07-01
Budget End
1986-06-30
Support Year
2
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Type
Schools of Medicine
DUNS #
City
Dallas
State
TX
Country
United States
Zip Code
75390
Stone, D K; Xie, X S (1988) Proton translocating ATPases: issues in structure and function. Kidney Int 33:767-74
Sudhof, T C; Stone, D K (1987) Purification of calelectrins. Methods Enzymol 139:30-5
McConnell, J D; Stone, D K; Johnson, L et al. (1987) Partial purification and characterization of dynein adenosine triphosphatase from bovine sperm. Biol Reprod 37:385-93
Xie, X S; Stone, D K (1986) Isolation and reconstitution of the clathrin-coated vesicle proton translocating complex. J Biol Chem 261:2492-5
Silva, F G; Sherrill, K; Spurgeon, S et al. (1986) High-level expression of the 32.5-kilodalton calelectrin in ductal epithelia as revealed by immunocytochemistry. Differentiation 33:175-83