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The Control of Oxidative Phosphorylation in the Adrenal Gland (Y1) Cell Line

  • James E.J. Murphy
  • Richard K. Porter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 645)

Abstract

We determined the proportion of oxygen consumption due to oxidative phosphorylation by mitochondria in an adrenal gland cell line (Y1 cells). In addition we determined the relative proportion of in situ mitochondrial oxygen consumption attributable to (i) proton leak and (ii) ATP turnover in these cells. This approach allowed use of top-down elasticity analysis to determine control of oxidative phosphorylation by mitochondrial (a) proton leak flux (b) substrate oxidation flux and (c) ATP turnover flux, as a function of changes in in situmitochondrial membrane potential. Our data show that resting oxygen consumptions rates of Y1 cells to be 87±7 nmolO/min/107 cells of which 38±3% was not due to oxidative phosphorylation. We demonstrated that mitochondrial proton leak accounted for 7±3% of total cellular oxygen consumption or 12±6% of resting mitochondrial oxygen consumption, with ATP turnover accounting for 55±3% of total cellular oxygen consumption or 78±6% of mitochondrial oxygen consumption. Control of resting mitochondrial oxygen consumption in Y1 cells was shared by (a) substrate oxidation flux (37±8%), (b) proton leak flux (15±8%) and (c) ATP turnover (56±8%). Our data demonstrate, for the first time, that the majority of oxygen consumption by resting Y1 cells is due to oxidative phosphorylation.

Keywords

Oxygen Consumption Oxidative Phosphorylation Mitochondrial Membrane Potential Oxygen Consumption Rate Proton Leak 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    D.F.S. Rolfe, A.J. Hulbert and M.D. Brand, Characteristics of mitochondrial proton leak and control of oxidative phosphorylation in the major oxygen-consuming tissues of the rat, Biochim. Biophys. Acta 1118,405-416 (1994).Google Scholar
  2. 2.
    D.F.S. Rolfe and M.D. Brand, The physiological significance of mitochondrial proton leak in animal cells and tissues, Biosci. Rep. 17, 9-16 (1997).PubMedCrossRefGoogle Scholar
  3. 3.
    M.D. Brand, L-F. Chien, E.K. Ainscow, D.F.S. Rolfe and R.K. Porter, The causes and functions of mitochondrial proton leak, Biochim. Biophys. Acta, 1187,132-139 (1994).PubMedCrossRefGoogle Scholar
  4. 4.
    G.C. Brown, P.L. Lakin-Thomas and M.D. Brand Control of respiration and oxidative phosphorylation in isolated rat liver cells, Eur. J. Biochem. 192, 355-362 (1990).PubMedCrossRefGoogle Scholar
  5. 5.
    R.K. Porter and M.D. Brand, Causes of differences in respiration rate of hepatocytes from mammals of different body mass, Am. J. Physiol. 269,R1213-R1224 (1995).PubMedGoogle Scholar
  6. 6.
    C.D. Nobes, G.C. Brown, Olive, P.N. and M.D. Brand, Non-ohmic proton conductance of the mitochondrial inner membrane in hepatocytes. J. Biol. Chem. 265, 12903-12909 (1990).PubMedGoogle Scholar
  7. 7.
    P.L. Pedersen, The cancer cell’s “power plants” as promising therapeutic targets: an overview. J. Bioenerg. Biomembr. 39, 1-12 (2007).PubMedCrossRefGoogle Scholar
  8. 8.
    R.D. Bruno and V.C Najr, Targeting cytochrome P450 enzymes: a new approach in anti-cancer drug development, Bioorg. Med. Chem. 15, 5047-5060 (2007).PubMedCrossRefGoogle Scholar
  9. 9.
    L.J. Cuprak and G. Sato, Nutritional requirements of mouse adrenal cortex tumor cells in culture. Exp. Cell Res. 52, 632-645 (1968).PubMedCrossRefGoogle Scholar
  10. 10.
    M.D. Brand, Measurement of mitochondrial protonmotive force, in Bioenergetics: A Practical Approach, edited by G.C. Brown and C.E. Cooper (IRL Press, Oxford,1995).Google Scholar
  11. 11.
    O.J.P. Joyce, M.K. Farmer, K.F. Tipton, and R.K. Porter, Oxidative Phosphorylation by in situ Synaptosomal Mitochondria from Whole Brain of Young and Old Rats. J. Neurochem. 86, 1032-1041 (2003)PubMedCrossRefGoogle Scholar
  12. 12.
    R.P. Hafner, G.C. Brand and M.D. Brand, Analysis of the control of respiration rate, phosphorylation rate, proton leak rate and protonmotive force in isolated mitochondria using the ’top-down’ approach of metabolic control theory, Eur. J. Biochem. 188, 313-319(1990).PubMedCrossRefGoogle Scholar
  13. 13.
    G.C. Brown, R.P. Hafner and M.D. Brand A ’top-down’ approach to the determination of control coefficients in metabolic control theory, Eur. J. Biochem. 188, 321-325 (1990).PubMedCrossRefGoogle Scholar
  14. 14.
    M.D. Brand, The proton leak across the mitochondrial inner membrane, Biochim. Biophys. Acta, 1018,128- 133 (1990).PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • James E.J. Murphy
    • 1
  • Richard K. Porter
    • 1
  1. 1.School of Biochemistry and ImmunologyTrinity College DublinIreland

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