AJP - Cell Physiology, Vol 258, Issue 1 C1-23, Copyright © 1990 by American Physiological Society

ARTICLES

Chemical modification as an approach to elucidation of sodium pump structure-function relations

C. H. Pedemonte and J. H. Kaplan
Department of Physiology, University of Pennsylvania, Philadelphia 19104-6085.

Chemical modification of specific residues in enzymes, with the characterization of the type of inhibition and properties of the modified activity, is an established approach in structure-function studies of proteins. This strategy has become more productive in recent years with the advances made in obtaining primary sequence information from gene-cloning technologies. This article discusses the application of chemical modification procedures to the study of the Na(+)-K(+)-ATPase protein. A wide array of information has become available about the kinetics, enzyme structure, and various conformational states as a result of the combined use of inhibitors, ligands, modifiers, and proteolytic enzymes. We will review a variety of reagents and approaches that have been employed to arrive at structure-function correlates and discuss critically the limits and ambiguities in the type of information obtained from these methodologies. Chemical modification of the Na(+)-pump protein has already provided a body of data and will, we anticipate, guide the efforts of mutagenesis studies in the future when suitable expression systems become available.

This article has been cited by other articles:

				N. T. Ruddock, K. L. Arnett, B. J. Wilson, and M. A. Milanick Chloro(2,2':6',2"-terpyridine) platinum inhibition of the renal Na+,K+-ATPase Am J Physiol Cell Physiol, June 1, 2003; 284(6): C1584 - C1592. [Abstract] [Full Text] [PDF]

				S. Teramachi, T. Imagawa, S. Kaya, and K. Taniguchi Replacement of Several Single Amino Acid Side Chains Exposed to the Inside of the ATP-binding Pocket Induces Different Extents of Affinity Change in the High and Low Affinity ATP-binding Sites of Rat Na/K-ATPase J. Biol. Chem., September 27, 2002; 277(40): 37394 - 37400. [Abstract] [Full Text] [PDF]

				L. A. Dunbar, P. Aronson, and M. J. Caplan A Transmembrane Segment Determines the Steady-state Localization of an Ion-transporting Adenosine Triphosphatase J. Cell Biol., February 21, 2000; 148(4): 769 - 778. [Abstract] [Full Text] [PDF]

				C. Gatto, S. J. Thornewell, J. P. Holden, and J. H. Kaplan Cys577 Is a Conformationally Mobile Residue in the ATP-binding Domain of the Na,K-ATPase alpha -Subunit J. Biol. Chem., August 27, 1999; 274(35): 24995 - 25003. [Abstract] [Full Text] [PDF]

				G. Blanco and R. W. Mercer Isozymes of the Na-K-ATPase: heterogeneity in structure, diversity in function Am J Physiol Renal Physiol, November 1, 1998; 275(5): F633 - F650. [Abstract] [Full Text] [PDF]

				T. Tsuda, S. Kaya, T. Yokoyama, Y. Hayashi, and K. Taniguchi Half-site Modification of Lys-480 of the Na+,K+-ATPase alpha -Chain with Pyridoxal 5'-Diphospho-5'-adenosine Reduces ATP-dependent Phosphorylation Stoichiometry from Half to a Quarter J. Biol. Chem., September 18, 1998; 273(38): 24334 - 24338. [Abstract] [Full Text] [PDF]

				K. Kato, Q. Shao, V. Elimban, A. Lukas, and N. S. Dhalla Mechanism of depression in cardiac sarcolemmal Na+-K+-ATPase by hypochlorous acid Am J Physiol Cell Physiol, September 1, 1998; 275(3): C826 - C831. [Abstract] [Full Text] [PDF]

				C. Gatto, A. X. Wang, and J. H. Kaplan The M4M5 Cytoplasmic Loop of the Na,K-ATPase, Overexpressed in Escherichia coli, Binds Nucleoside Triphosphates with the Same Selectivity as the Intact Native Protein J. Biol. Chem., April 24, 1998; 273(17): 10578 - 10585. [Abstract] [Full Text] [PDF]

				L. Liu and A. Askari Evidence for the Existence of Two ATP-sensitive Rb+ Occlusion Pockets within the Transmembrane Domains of Na+/K+-ATPase J. Biol. Chem., May 30, 1997; 272(22): 14380 - 14386. [Abstract] [Full Text] [PDF]

				S. Lutsenko, S. Daoud, and J. H. Kaplan Identification of Two Conformationally Sensitive Cysteine Residues at the Extracellular Surface of the Na,K-ATPase alpha -Subunit J. Biol. Chem., February 21, 1997; 272(8): 5249 - 5255. [Abstract] [Full Text] [PDF]

				E. C. Rabon, M. Hoggatt, and K. Smillie Transmembrane Carboxyl Residues Are Essential for Cation-dependent Function in the Gastric H,K-ATPase J. Biol. Chem., December 13, 1996; 271(50): 32137 - 32146. [Abstract] [Full Text] [PDF]

				J. M. Arguello, R. D. Peluffo, J. Feng, J. B Lingrel, and J. R. Berlin Substitution of Glutamic 779with Alanine in the Na,K-ATPase alpha Subunit Removes Voltage Dependence of Ion Transport J. Biol. Chem., October 4, 1996; 271(40): 24610 - 24616. [Abstract] [Full Text] [PDF]

				Y.-K. Hu, J. F. Eisses, and J. H. Kaplan Expression of an Active Na,K-ATPase with an alpha -Subunit Lacking All Twenty-three Native Cysteine Residues J. Biol. Chem., September 22, 2000; 275(39): 30734 - 30739. [Abstract] [Full Text] [PDF]