| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Cell Physiology, Vol 265, Issue 6 C1562-C1570, Copyright © 1993 by American Physiological Society
ARTICLES |
D. C. Chow and J. G. Forte
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
The gastric proton pump, H(+)-K(+)-ATPase, is composed of alpha- and beta-subunits. The 95-kDa alpha-subunit has been referred to as the catalytic subunit containing sites for ATP binding and phosphorylation. The beta-subunit is a glycoprotein with a 34-kDa core peptide that has a single transmembrane segment, a small cytoplasmic NH2-terminal, and a large extracellular COOH-terminal domain with seven potential N-linked glycosylation sites. To further study the beta-subunit, we developed monoclonal antibodies that identified a 52-kDa mannose-rich glycoprotein that was deglycosylated by endoglycosidase H such that six transient intermediates were identified, as well as a 34-kDa beta-subunit core peptide. These observations suggest that the beta-subunit is synthesized as a 52-kDa glycoprotein with seven N-linked precursor high-mannose oligosaccharides that mature into complex oligosaccharides. One antibody, 2G11, inhibits the K(+)-stimulated ATP hydrolysis as well as K(+)-stimulated p-nitrophenyl phosphatase (pNPPase) activity of the H(+)-K(+)-ATPase. Kinetic studies revealed that 2G11 inhibited maximum velocity (Vmax) of ATP hydrolysis by approximately 50% with no change in the Km for K+, whereas, for pNPPase both Vmax and Km were altered. These studies demonstrate a functional role for the beta-subunit in the H(+)-K(+)-ATPase activity, especially the K(+)-induced conformational states.
This article has been cited by other articles:
|
|
 |
|
  D. H. Malinowska, A. M. Sherry, K. P. Tewari, and J. Cuppoletti Gastric parietal cell secretory membrane contains PKA- and acid-activated Kir2.1 K+ channels Am J Physiol Cell Physiol, March 1, 2004; 286(3): C495 - C506. [Abstract] [Full Text]
|
|
|
|
 |
|
 C. E.M. De Block, I. H. De Leeuw, J. J.P.M. Bogers, P. A. Pelckmans, M. M. Ieven, E. A.E. Van Marck, K. L. Van Acker, and L. F. Van Gaal Autoimmune Gastropathy in Type 1 Diabetic Patients With Parietal Cell Antibodies: Histological and clinical findings Diabetes Care, January 1, 2003; 26(1): 82 - 88. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Petrovic, Z. Wang, L. Ma, U. Seidler, J. G. Forte, G. E. Shull, and M. Soleimani Colocalization of the apical Cl-/HCO3- exchanger PAT1 and gastric H-K-ATPase in stomach parietal cells Am J Physiol Gastrointest Liver Physiol, November 1, 2002; 283(5): G1207 - G1216. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Scheinecker, R. McHugh, E. M. Shevach, and R. N. Germain Constitutive Presentation of a Natural Tissue Autoantigen Exclusively by Dendritic Cells in the Draining Lymph Node J. Exp. Med., October 21, 2002; 196(8): 1079 - 1090. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Muto Potassium Transport in the Mammalian Collecting Duct Physiol Rev, January 1, 2001; 81(1): 85 - 116. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. T. Okamoto, D. C. Chow, and A. J. G. Forte Interaction of alpha - and beta -subunits in native H-K-ATPase and cultured cells transfected with H-K-ATPase beta -subunit Am J Physiol Cell Physiol, April 1, 2000; 278(4): C727 - C738. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Asano, K. Kawada, T. Kimura, A. V. Grishin, M. J. Caplan, and N. Takeguchi The Roles of Carbohydrate Chains of the beta -Subunit on the Functional Expression of Gastric H+,K+-ATPase J. Biol. Chem., March 17, 2000; 275(12): 8324 - 8330. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Asano, T. Kimura, S. Ueno, M. Kawamura, and N. Takeguchi Chimeric Domain Analysis of the Compatibility between H+,K+-ATPase and Na+,K+-ATPase beta -Subunits for the Functional Expression of Gastric H+,K+-ATPase J. Biol. Chem., August 6, 1999; 274(32): 22257 - 22265. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Koenderink, H. G. P. Swarts, H. P. H. Hermsen, and J. J. H. H. M. De Pont The {beta}-Subunits of Na+,K+-ATPase and Gastric H+,K+-ATPase Have a High Preference for Their Own {alpha}-Subunit and Affect the K+ Affinity of These Enzymes J. Biol. Chem., April 23, 1999; 274(17): 11604 - 11610. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. G. Campbell, I. D. Weiner, C. S. Wingo, and B. D. Cain H-K-ATPase in the RCCT-28A rabbit cortical collecting duct cell line Am J Physiol Renal Physiol, February 1, 1999; 276(2): F237 - F245. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Lambrecht, Z. Corbett, D. Bayle, S. J. D. Karlish, and G. Sachs Identification of the Site of Inhibition by Omeprazole of a alpha -beta Fusion Protein of the H,K-ATPase Using Site-directed Mutagenesis J. Biol. Chem., May 29, 1998; 273(22): 13719 - 13728. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. T. Okamoto, S. M. Karam, Y. Y. Jeng, J. G. Forte, and J. R. Goldenring Identification of clathrin and clathrin adaptors on tubulovesicles of gastric acid secretory (oxyntic) cells Am J Physiol Cell Physiol, April 1, 1998; 274(4): C1017 - C1029. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Z. Levine, M. Iacovitti, S. Buckman, B. Luck, M. T. Hincke, K. D. Burns, and J. N. Fryer K depletion stimulates in vivo HCO3 reabsorption in surviving rat distal tubules Am J Physiol Renal Physiol, April 1, 1998; 274(4): F665 - F672. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Koenderink, H. G. P. Swarts, H. C. Stronks, H. P. H. Hermsen, P. H. G. M. Willems, and J. J. H. H. M. De Pont Chimeras of X+,K+-ATPases. THE M1-M6 REGION OF Na+,K+-ATPase IS REQUIRED FOR Na+-ACTIVATED ATPase ACTIVITY, WHEREAS THE M7-M10 REGION OF H+,K+-ATPase IS INVOLVED IN K+ DE-OCCLUSION J. Biol. Chem., April 6, 2001; 276(15): 11705 - 11711. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
