The overall aim of this project is to investigate the role of the plasma membrane Ca2+ pump in Ca2+ transport in kidney, particularly the kidneys of rat. Both monoclonal antibodies and gene cloning techniques (polymerase chain reaction) will be used to explore the expression of different isozymes along the tubule. It is likely that the Ca2+ pump has multiple roles in the nephron, including its involvement in control of intracellular Ca2+ signalling and its role in transcellular transport of Ca2+ (by means of which the kidney recaptures Ca2+ from the urine). Different isozymes of the Ca2+ pump are likely to be involved in different roles, and probably differ from one another in properties such as calcium affinity, regulation by protein kinases and sensitivity to calmodulin. Determination of the distribution of Ca2+ pump isoforms along the nephron will provide fundamental knowledge needed to understand renal handling of calcium in health and disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK044902-02
Application #
3246423
Study Section
Pathology A Study Section (PTHA)
Project Start
1992-05-01
Project End
1997-04-30
Budget Start
1993-05-01
Budget End
1994-04-30
Support Year
2
Fiscal Year
1993
Total Cost
Indirect Cost
Name
Mayo Clinic, Rochester
Department
Type
DUNS #
City
Rochester
State
MN
Country
United States
Zip Code
55905
Caride, A J; Chini, E N; Penniston, J T et al. (1999) Selective decrease of mRNAs encoding plasma membrane calcium pump isoforms 2 and 3 in rat kidney. Kidney Int 56:1818-25
Caride, A J; Chini, E N; Homma, S et al. (1998) mRNA encoding four isoforms of the plasma membrane calcium pump and their variants in rat kidney and nephron segments. J Lab Clin Med 132:149-56
Caride, A J; Chini, E N; Homma, S et al. (1998) mRNAs coding for the calcium-sensing receptor along the rat nephron: effect of a low-phosphate diet. Kidney Blood Press Res 21:305-9
Apicella, S; Chen, S; Bing, R et al. (1997) Plasmalemmal ATPase calcium pump localizes to inner and outer hair bundles. Neuroscience 79:1145-51
Hillman, D E; Chen, S; Bing, R et al. (1996) Ultrastructural localization of the plasmalemmal calcium pump in cerebellar neurons. Neuroscience 72:315-24
Caride, A J; Filoteo, A G; Enyedi, A et al. (1996) Detection of isoform 4 of the plasma membrane calcium pump in human tissues by using isoform-specific monoclonal antibodies. Biochem J 316 ( Pt 1):353-9
Caride, A J; Chini, E N; Yamaki, M et al. (1995) Unique localization of mRNA encoding plasma membrane Ca2+ pump isoform 3 in rat thin descending loop of Henle. Am J Physiol 269:F681-5