Interplay of Ca2+ and Mg2+ in Sodium-Calcium Exchanger and in Other Ca2+-Binding Proteins: Magnesium, Watchdog That Blocks Each Turn if Able

  • Dmitri O. LevitskyEmail author
  • Masayuki Takahashi
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 961)


Sodium-calcium exchange across plasma membrane is regulated by intracellular calcium ions. The sodium-calcium exchanger (NCX1) is activated by successive saturation of numerous Ca2+-binding sites located in the intracellular loop of the protein. The progressive saturation of the binding domain CBD12 by Ca2+ results in a series of conformational changes of CBD12 as well as of entire NCX1 molecule. Like other soluble and membrane Ca2+-binding proteins, NCX1 can also be regulated by Mg2+ that antagonises Ca2+ at the level of divalent cation-binding sites. This chapter summarises data on Mg2+ impacts in the cells. Regulatory action of Mg2+ on intracellular Ca2+-dependent processes can be achieved due to changes of its cytoplasmic level, which take place in the range of [Mg2+]i from 0.5 to 3 mM. Under normal conditions, these changes are ensured by activation of plasmalemmal Mg2+ transport systems and by variations in ATP level in cytoplasm. In heart and in brain, some pathological conditions, such as hypoxia, ischemia and ischemia followed by reperfusion, are associated with an important increase in intracellular Ca2+. The tissue damage due to Ca2+ overload may be prevented by Mg2+. The protective actions of Mg2+ can be achieved due to its ability to compete with Ca2+ for the binding sites in a number of proteins responsible for the rise in intracellular free Ca2+, including NCX1, in case when the reverse mode of Na+/Ca2+ exchange becomes predominant. Saturation of CBD12 by Mg2+ results in important changes of NCX1 conformation. Modulating actions of Mg2+ on the conformation of NCX1 were detected at a narrow range of Mg2+ concentration, from 0.5 to 1 mM. These data support an idea that variations of intracellular Mg2+ could modify transmembrane Ca2+ movements ensured by NCX1.


Calcium Magnesium Na+/Ca2+ exchanger NCX1 Calcium-/magnesium-binding proteins Ca2+-binding sites 



We thank M. Hilge for providing NCX1 plasmids. We are thankful to our students E. Foucault, Ou. Louahdi, A. Menou, L. Diakite and M. Mekideche for their participation in a number of experiments.


  1. D. Allouche, J. Parello, Y.H. Sanejouand, Ca2+/Mg2+ exchange in parvalbumin and other EF-hand proteins. A theoretical study. J. Mol. Biol. 285, 857–873 (1999)PubMedCrossRefGoogle Scholar
  2. L. Bao, C. Kaldany, E.C. Holmstrand, D.H. Cox, Mapping the BKCa channel’s “Ca2+ bowl”: side-chains essential for Ca2+ sensing. J. Gen. Physiol. 123, 475–489 (2004)PubMedCrossRefGoogle Scholar
  3. G.M. Besserer, M. Ottolia, D.A. Nicoll, V. Chaptal, D. Cascio, K.D. Philipson, J. Abramson, The second Ca2+-binding domain of the Na+ Ca2+ exchanger is essential for regulation: crystal structures and mutational analysis. Proc. Natl. Acad. Sci. U. S. A. 104, 18467–18472 (2007)PubMedCrossRefGoogle Scholar
  4. I. Bezprozvanny, J. Watras, B.E. Ehrlich, Bell-shaped calcium-response curves of Ins(1,4,5)P3- and calcium-gated channels from endoplasmic reticulum of cerebellum. Nature 351, 751–754 (1991)PubMedCrossRefGoogle Scholar
  5. A.L. Blatz, K.L. Magleby, Calcium-activated potassium channels. Trends Neurosci. 10, 463–467 (1987)CrossRefGoogle Scholar
  6. M.P. Blaustein, W.J. Lederer, Sodium/calcium exchange: its physiological implications. Physiol. Rev. 79, 763–854 (1999)PubMedGoogle Scholar
  7. L. Boyman, H. Mikhasenko, R. Hiller, D. Khananshvili, Kinetic and equilibrium properties of regulatory calcium sensors of NCX1 protein. J. Biol. Chem. 284, 6185–6193 (2009)PubMedCrossRefGoogle Scholar
  8. S. Brunet, T. Scheuer, W.A. Catterall, Cooperative regulation of Ca(v)1.2 channels by intracellular Mg2+, the proximal C-terminal EF-hand, and the distal C-terminal domain. J. Gen. Physiol. 134, 81–94 (2009)PubMedCrossRefGoogle Scholar
  9. C. Cefaratti, A. Romani, Modulation of Na+/Mg2+ exchanger stoichiometry ratio by Cl ions in basolateral rat liver plasma membrane vesicles. Mol. Cell. Biochem. 351, 133–142 (2011)PubMedCrossRefGoogle Scholar
  10. M.M. Chien, K.E. Zahradka, M.K. Newell, J.H. Freed, Fas-induced B cell apoptosis requires an increase in free cytosolic magnesium as an early event. J. Biol. Chem. 274, 7059–7066 (1999)PubMedCrossRefGoogle Scholar
  11. B.E. Corkey, J. Duszynski, T.L. Rich, B. Matschinsky, J.R. Williamson, Regulation of free and bound magnesium in rat hepatocytes and isolated mitochondria. J. Biol. Chem. 261, 2567–2574 (1986)PubMedGoogle Scholar
  12. L.J. Dai, G. Ritchie, D. Kerstan, H.S. Kang, D.E. Cole, G.A. Quamme, Magnesium transport in the renal distal convoluted tubule. Physiol. Rev. 81, 51–84 (2001)PubMedGoogle Scholar
  13. H. Ebel, R. Kreis, T. Gunther, Regulation of Na+/Mg2+ antiport in rat erythrocytes. Biochim. Biophys. Acta 1664, 150–160 (2004)PubMedCrossRefGoogle Scholar
  14. L. Eichelberger, F.C. McLean, W.A. Catterall, The distribution of calcium and magnesium between the cells and the extracellular fluids of skeletal muscle and liver in dogs. J. Biol. Chem. 142, 467–476 (1942)Google Scholar
  15. S. Gasser, N. Bareza, E. Scheer, D. Pruthi, R. Gasser, U.E. Spichiger-Keller, E. Toferer, Free intracellular magnesium remains uninfluenced by changes of extracellular magnesium in cardiac guinea pig papillary muscle. J. Clin. Basic Cardiol. 8, 29–32 (2005)Google Scholar
  16. J. Golowasch, A. Kirkwood, C. Miller, Allosteric effects of Mg2+ on the gating of Ca2+-activated K+ channels from mammalian skeletal muscle. J. Exp. Biol. 124, 5–13 (1986)PubMedGoogle Scholar
  17. R.D. Grubbs, S.D. Collins, M.E. Maguire, Differential compartmentation of magnesium and calcium in murine S49 lymphoma cells. J. Biol. Chem. 259, 12184–12192 (1984)PubMedGoogle Scholar
  18. R.D. Grubbs, P.A. Beltz, K.L. Koss, Practical considerations for using mag-fura-2 to measure cytosolic free magnesium. Magnes. Trace Elem. 10, 142–150 (1991)PubMedGoogle Scholar
  19. M.C. Haigney, S. Wei, S. Kaab, E. Griffiths, R. Berger, R. Tunin, D. Kass, W.G. Fisher, B. Silver, H. Silverman, Loss of cardiac magnesium in experimental heart failure prolongs and destabilizes repolarization in dogs. J. Am. Coll. Cardiol. 31, 701–706 (1998)PubMedCrossRefGoogle Scholar
  20. J.P. Headrick, R.J. Willis, Cytosolic free magnesium in stimulated, hypoxic, and underperfused rat heart. J. Mol. Cell. Cardiol. 23, 991–999 (1991)PubMedCrossRefGoogle Scholar
  21. M. Henrich, K.J. Buckler, Effects of anoxia, aglycemia, and acidosis on cytosolic Mg2+, ATP, and pH in rat sensory neurons. Am. J. Physiol. Cell Physiol. 294, C280–C294 (2008)PubMedCrossRefGoogle Scholar
  22. M. Hilge, J. Aelen, G.W. Vuister, Ca2+ regulation in the Na+/Ca2+ exchanger involves two markedly different Ca2+ sensors. Mol. Cell 22, 15–25 (2006)PubMedCrossRefGoogle Scholar
  23. J. Kimura, A. Noma, H. Irisawa, Na-Ca exchange current in mammalian heart cells. Nature 319, 596–597 (1986)PubMedCrossRefGoogle Scholar
  24. C.O. Lee, P. Abete, M. Pecker, J.K. Sonn, M. Vassalle, Strophanthidin inotropy: role of intracellular sodium ion activity and sodium-calcium exchange. J. Mol. Cell. Cardiol. 17, 1043–1053 (1985)PubMedCrossRefGoogle Scholar
  25. D.O. Levitsky, D.A. Nicoll, K.D. Philipson, Identification of the high affinity Ca2+-binding domain of the cardiac Na+-Ca2+ exchanger. J. Biol. Chem. 269, 22847–22852 (1994)PubMedGoogle Scholar
  26. D.O. Levitsky, B. Fraysse, C. Leoty, D.A. Nicoll, K.D. Philipson, Cooperative interaction between Ca2+ binding sites in the hydrophilic loop of the Na+-Ca2+ exchanger. Mol. Cell. Biochem. 160–161, 27–32 (1996)PubMedCrossRefGoogle Scholar
  27. S. Matsuoka, D.A. Nicoll, R.F. Reilly, D.W. Hilgemann, K.D. Philipson, Initial localization of regulatory regions of the cardiac sarcolemmal Na+-Ca2+ exchanger. Proc. Natl. Acad. Sci. U. S. A. 90, 3870–3874 (1993)PubMedCrossRefGoogle Scholar
  28. G. Meissner, Ryanodine activation and inhibition of the Ca2+ release channel of sarcoplasmic reticulum. J. Biol. Chem. 261, 6300–6306 (1986)PubMedGoogle Scholar
  29. K.W. Muir, Magnesium in stroke treatment. Postgrad. Med. J. 78, 641–645 (2002)PubMedCrossRefGoogle Scholar
  30. E. Murphy, C. Steenbergen, L.A. Levy, B. Raju, R.E. London, Cytosolic free magnesium levels in ischemic rat heart. J. Biol. Chem. 264, 5622–5627 (1989)PubMedGoogle Scholar
  31. S. Nakayama, T. Tomita, Regulation of intracellular free magnesium concentration in the taenia of guinea-pig caecum. J. Physiol. 435, 559–572 (1991)PubMedGoogle Scholar
  32. D.A. Nicoll, M.R. Sawaya, S. Kwon, D. Cascio, K.D. Philipson, J. Abramson, The crystal structure of the primary Ca2+ sensor of the Na+/Ca2+ exchanger reveals a novel Ca2+ binding motif. J. Biol. Chem. 281, 21577–21581 (2006)PubMedCrossRefGoogle Scholar
  33. W. Paschen, Glutamate excitotoxicity in transient global cerebral ischemia. Acta Neurobiol. Exp. (Wars) 56, 313–322 (1996)Google Scholar
  34. S.M. Pogwizd, M. Qi, W. Yuan, A.M. Samarel, D.M. Bers, Upregulation of Na+/Ca2+ exchanger expression and function in an arrhythmogenic rabbit model of heart failure. Circ. Res. 85, 1009–1019 (1999)PubMedCrossRefGoogle Scholar
  35. G.A. Quamme, Molecular identification of ancient and modern mammalian magnesium transporters. Am. J. Physiol. Cell Physiol. 298, C407–C429 (2010)PubMedCrossRefGoogle Scholar
  36. H. Reinecke, R. Studer, R. Vetter, J. Holtz, H. Drexler, Cardiac Na+/Ca2+ exchange activity in patients with end-stage heart failure. Cardiovasc. Res. 31, 48–54 (1996)PubMedGoogle Scholar
  37. A. Romani, C. Marfella, A. Scarpa, Regulation of magnesium uptake and release in the heart and in isolated ventricular myocytes. Circ. Res. 72, 1139–1148 (1993)PubMedCrossRefGoogle Scholar
  38. M. Schreiber, A. Yuan, L. Salkoff, Transplantable sites confer calcium sensitivity to BK channels. Nat. Neurosci. 2, 416–421 (1999)PubMedCrossRefGoogle Scholar
  39. M.D. Snavely, S.A. Gravina, T.T. Cheung, C.G. Miller, M.E. Maguire, Magnesium transport in Salmonella typhimurium. Regulation of mgtA and mgtB expression. J. Biol. Chem. 266, 824–829 (1991)PubMedGoogle Scholar
  40. R.M. Touyz, E.L. Schiffrin, Angiotensin II and vasopressin modulate intracellular free magnesium in vascular smooth muscle cells through Na+-dependent protein kinase C pathways. J. Biol. Chem. 271, 24353–24358 (1996)PubMedCrossRefGoogle Scholar
  41. M. Wang, M. Tashiro, J.R. Berlin, Regulation of L-type calcium current by intracellular magnesium in rat cardiac myocytes. J. Physiol. 555, 383–396 (2004)PubMedCrossRefGoogle Scholar
  42. S.K. Wei, J.F. Quigley, S.U. Hanlon, B. O’Rourke, M.C. Haigney, Cytosolic free magnesium modulates Na/Ca exchange currents in pig myocytes. Cardiovasc. Res. 53, 334–340 (2002)PubMedCrossRefGoogle Scholar
  43. R.E. White, H.C. Hartzell, Effects of intracellular free magnesium on calcium current in isolated cardiac myocytes. Science 239, 778–780 (1988)PubMedCrossRefGoogle Scholar
  44. A. Zahradnikova, Z. Kubalova, J. Pavelkova, S. Gyorke, I. Zahradnik, Activation of calcium release assessed by calcium release-induced inactivation of calcium current in rat cardiac myocytes. Am. J. Physiol. Cell Physiol. 286, C330–C341 (2004)PubMedCrossRefGoogle Scholar
  45. X. Zhang, C.R. Solaro, C.J. Lingle, Allosteric regulation of BK channel gating by Ca2+ and Mg2+ through a nonselective, low affinity divalent cation site. J. Gen. Physiol. 118, 607–636 (2001)PubMedCrossRefGoogle Scholar
  46. J. Zhang, F. Zhao, Y. Zhao, J. Wang, L. Pei, N. Sun, J. Shi, Hypoxia induces an increase in intracellular magnesium via transient receptor potential melastatin 7 (TRPM7) channels in rat hippocampal neurons in vitro. J. Biol. Chem. 286, 20194–20207 (2011)PubMedCrossRefGoogle Scholar

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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Unité de Fonctionnalité et Ingénierie des Protéines, FRE-CNRS 3478, Faculté des Sciences et des TechniquesUniversité de NantesNantes Cedex 03France

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