1887

Abstract

Influx of Cainto cells of was measured under non-steady-state conditions, which enable measurements of the initial rate of transport across plasma membranes without interference by the vacuolar Catransport system. Removal of glucose from the incubation medium led to inactivation of Cainflux within 5 min. Readdition of glucose led to a transient increase in the rate of Catransport, reaching a peak after 3–5 min. A second increase was observed 60–80 min later. To examine whether the first transient activation of Cainflux by glucose was mediated by membrane hyperpolarization, influx of Cawas measured in the presence and absence of metabolic substrates (glucose, glycerol, and glucose plus antimycin A) in cells hyperpolarized to different values of membrane potential (∆ψ). Logarithms of the rate of Cainflux were plotted against values of ∆ψ. Two different slopes were obtained, depending upon whether the metabolic substrate was present or absent. Cainflux in the presence of the metabolic substrates was always higher than expected by their effect on ∆ψ. Glycerol plus antimycin A did not affect Cainflux. It was concluded that metabolized substrates activate Cainflux not only by effects on ∆ψ but also by additional mechanism(s). Since no simple correlation between Cainflux and intracellular ATP levels was observed, it was concluded that ATP levels do not affect the initial rates of Catransport across the plasma membrane of .

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1990-05-01
2024-12-06
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References

  1. Alkon D.L., Rasmussen H. 1988; A spatial-temporal model of cell activation. Science 239:998–1004
    [Google Scholar]
  2. Borst-Pauwels G.W.F.H. 1981; Ion transport in yeast. Biochimica et Biophysica Acta 650:88–127
    [Google Scholar]
  3. Borst-Pauwels G.W.F.H., Van De Mortel J.B.J., Mulders D., Korthout H., Theuvenet A.P.R. 1988; Indications that the transient hyperpolarization of yeast by glucose at pH 7 is caused by opening of specific K+ channels. In Proceedings of Contributions to the 6th Small Meeting on Yeast-Transport and Energetics, Dortmund, FRG, pp 15–16 Kuschmitz D. Edited by Dortmund: Max Planck Institut;
    [Google Scholar]
  4. Boutry M., Foury F., Goffeau A. 1977; Energy dependent uptake of calcium by the yeast Schizosaccharomyces pombe. Biochimica et Biophysica Acta 464:602–612
    [Google Scholar]
  5. Eilam Y. 1984; Effects of phenothiazine on inhibition of plasma membrane ATPase and hyperpolarization of cell membranes in the yeast Saccharomyces cerevisiae. Biochimica et Biophysica Acta 769:601–610
    [Google Scholar]
  6. Eilam Y., Chernichovsky D. 1987; Uptake of Ca2+ driven by membrane potential in energy depleted yeast cells. Journal of General Microbiology 133:1641–1649
    [Google Scholar]
  7. Eilam Y., Othman M. 1988; Mechanism of activation of Ca2+influx by metabolic substrate in Saccharomyces cerevisiae. In Proceedings of Contributions to the 6th Small Meeting on Yeast Transport and Energetics, Dortmund, FRG, pp 17–18 Kuschmitz D. Edited by Dortmund: Max Planck Institut;
    [Google Scholar]
  8. Eilam Y., Lavi H., Grossowicz N. 1985a; Cytoplasmic Ca2+homeostasis maintained by a vacuolar Ca2+ transport system in the yeast Saccharomyces cerevisiae. Journal of General Microbiology 131:623–629
    [Google Scholar]
  9. Eilam Y., Lavi H., Grossowicz N. 1985b; Active extrusion of potassium in the yeast Saccharomyces cerevisiae induced by low concentrations of trifluoperazine. Journal of General Microbiology 131:2555–2564
    [Google Scholar]
  10. Kaibuchi K., Miyajima A., Arai K.I., Matsumoto K. 1986; Possible involvement of JL45-encoded proteins in glucose-induced inositol phospholipid turnover in Saccharomyces cerevisiae. Journal of Cell Biology 83:8172–8176
    [Google Scholar]
  11. Kuschmitz D., Hess B. 1987; Linear and non linear phenomena irr the interaction between glycolysis and plasma membrane in yeast. In Proceedings of Contributions to the 5th Small Meeting on Yeast Transport and Energetics, Louvain La Neuve, Belgium, pp 44–45 Goffeau A. Edited by Louvain La Neuve: Universite Catholique de Louvain;
    [Google Scholar]
  12. Moolenaar W.H., Tertoolen L.G.J., Delaat S.W. 1984; Growth factors immediately raise cytoplasmic free Ca2+ in human fibroblasts. Journal of Biological Chemistry 259:8066–8069
    [Google Scholar]
  13. Ohsumi Y., Anraku Y. 1983; Calcium transport driven by a proton motive force in vacuolar membrane vesicles of Saccharomyces cerevisiae. Journal of Biological Chemistry 258:5614–5617
    [Google Scholar]
  14. Roomans G.M., Theuvenet A.P.R., Van Den Berg TH.P.R., Borst-Pauwels C.W.F.H. 1979; Kinetics of Ca2+ and Sr2+uptake by yeast.Effects of pH, cations and phosphate. Biochimica et Biophysica Acta 551:187–196
    [Google Scholar]
  15. Serrano R. 1983; In vivo glucose activation of the yeast plasma membrane ATPase. FEBS Letters 156:11–14
    [Google Scholar]
  16. Smith J.S., Coronado R., Meissner G. 1986; Single channel measurements of calcium release channel from skeletal muscle sarcoplasmic reticulum. Activation by Ca2+ and ATP and modulation by Mg2+. Journal of General Physiology 88:573–588
    [Google Scholar]
  17. Truneh A., Albert F., Golstein P., Schmitt-Verhulst A.M. 1985; Early steps of lymphocyte activation bypassed by synergy between calcium ionophores and phorbol ester. Nature; London: 313318–320
    [Google Scholar]
  18. VanDeMortel J.B.J., Mulders D., Korthout H., Theuvenet A.P.R., Borst-Pauwels G.W.F.H. 1988; Transient hyperpolarization of yeast by glucose and ethanol. Biochimica et Biophysica Acta 936:421–428
    [Google Scholar]
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