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Artificial control of cytoplasmic pH and its bearing on cytoplasmic streaming, electrogenesis and excitability of characeae cells

  • Masashi Tazawa
  • Teruo Shimmen
Article

Abstract

Effects of changing the cytoplasmic pH on the cytoplasmic streaming, membrane potential and membrane excitability were studied in tonoplast-free cells ofChara australis andNitellopsis obtusa. The cytoplasmic pH was varied by internal perfusion of pH-buffered media.Nitellopsis cells were perfused only once, whileChara cells were perfused twice to control the pH more accurately.

In both materials the rate of cytoplasmic streaming was maximum at about pH 7, low at pH 8.5–9 and almost zero at pH 5–5.5. The membrane potential was most negative at about pH 7. InChara the membrane potential supported by Mg·ATP was strongly inhibited at pH 5.5, and almost zero at pH 9, supporting the results obtained by Fujiiet al. (1979) on cells ofChara australis which were perfused once. The action potential could be induced by electrical stimulation inChara at pH 6.0–9.0 and inNitellopsis at pH 6.6–7.9. The membrane resistance ofNitellopsis was high at acidic and neutral pH values and low at alkaline pH, while that ofChara was low at both acidic and alkaline pH values.

Key words

Action potential Characeae Cytoplasmic streaming H+ pump Membrane potential pH (cytoplasm) 

Abbreviations

ATP

adenosine 5′-triphosphate

DMGA

β, β-dimethylglutaric acid

EGTA

ethyleneglyco-bis-(β-aminoethyl ether)N,N′-tetraacetic acid

HEPES

N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid

K-MSA

K-methanesulfonic acid

MES

2-(N-morpholino) ethanesulfonic acid

TAPS

N-Tris (hydroxymethyl)methylaminopropanesulfonic acid

Tricine

N-Tris(hydroxymethyl)methylglycine

References

  1. Bass, L. andW.J. Moore. 1973. The role of protons in nerve conduction. Prog. Biophys. Mol. Biol.27: 143–171.CrossRefGoogle Scholar
  2. Bowman, B.J. andC.W. Slayman. 1979. The effects of vanadate on the plasma membrane ATPase ofNeurospora crassa. J. Biol. Chem.254: 2928–2934.PubMedGoogle Scholar
  3. Brodwick, M.S. andD.C. Eaton. 1978. Sodium channel inactivation in squid axon is removed by high internal pH or tyrosine-specific reagents. Science200: 1494–1496.PubMedGoogle Scholar
  4. Fujii, S., T. Shimmen andM. Tazawa. 1979. Effect of intracellular pH on the light-induced potential change and electrogenic activity in tonoplast-free cells ofChara australis. Plant Cell Physiol.20: 1315–1328.Google Scholar
  5. Gaffey, C.T. andL.J. Mullins. 1958. Ion fluxes during the action potential inChara. J. Physiol.144: 505–524.PubMedGoogle Scholar
  6. Haapanen, L. andC.R. Skoglund. 1967. Recording of the ionic efflux during single action potentials inNitellopsis obtusa by means of high-frequency reffectometry. Acta Physiol. Scand.69: 51–68.PubMedGoogle Scholar
  7. Kamiya, N. andK. Kuroda. 1956. Velocity distribution of the protoplasmic streaming inNitella cells. Bot. Mag. Tokyo69: 543–554.Google Scholar
  8. Kato, T. andY. Tonomura. 1977. Identification of myosin inNitella flexilis. J. Biochem.82: 777–782.PubMedGoogle Scholar
  9. Kikuyama, M. andM. Tazawa 1976. Characteristics of the vacuolar membrane ofNitella. J. Membrane Biol.,30: 225–247.CrossRefGoogle Scholar
  10. Kishimoto, U. 1964. Current voltage relations inNitella. Jap. J. Physiol.14: 515–527.Google Scholar
  11. Lucas, W.J. andT. Shimmen 1981. Intracellular perfusion and cell centrifugation studies on plasmalemma transport processes inChara corallina J. Membrane Biol.58: 227–237.CrossRefGoogle Scholar
  12. Maruyama, K., S. Kimura, T. Ishii, M. Kuroda, K. Ohashi andS. Muramatsu. 1977. β-actinin, a regulatory protein of muscle. J. Biochem.81: 215–232.PubMedGoogle Scholar
  13. Oda, K. 1976. Simultaneous recording of potassium and chloride effluxes during an action potential inChara corallina. Plant Cell Physiol.17: 1085–1088.Google Scholar
  14. Raven, J.A. andF.A. Smith. 1973. The regulation of intracellular pH as a fundamental biological process.In: W.P. Anderson, ed., Ion Transport in Plants pp. 271–282. Academic Press, New York.Google Scholar
  15. —and—. 1978. Effect of temperature and external pH on the cytoplasmic pH ofChara corallina. J. Exp. Bot.29: 853–866.Google Scholar
  16. Scarborough, G.A. 1980. Proton translocation catalyzed by the electrogenic ATPase in the plasma membrane ofNeurospora. Biochemistry19: 2925–2931.PubMedCrossRefGoogle Scholar
  17. Shimmen, T. andM. Tazawa. 1977. Control of membrane potential and excitability ofChara cells with ATP and Mg2+ J Membrane Biol.37: 167–192.CrossRefGoogle Scholar
  18. —and—. 1980. Dependency of H+ efflux on ATP in cells ofChara australis. Plant Cell Physiol.21: 1007–1013.Google Scholar
  19. Shimmen,T. and M. Tazawa. 1982. Effect of intracellular vanadate on electrogenesis, excitability and cytoplasmic streaming inNitellopsis obtusa. Plant Cell Physiol. (in press).Google Scholar
  20. Smith, F.A. andN.A. Walker. 1976. Chloride transport inChara corallina and the electrochemical potential difference for hydrogen ions. J. Exp. Bot.27: 451–459.Google Scholar
  21. Spanswick, R.M. andA.G. Miller. 1977. Measurement of the cytoplasmic pH inNitella translucens. Plant Physiol.59: 664–666.PubMedCrossRefGoogle Scholar
  22. Tasaki, I., I. Singer andT. Takenaka 1965. Effects of internal and external ionic environment on excitability of squid giant axon. J. Gen. Physiol.48: 1095–1123.PubMedCrossRefGoogle Scholar
  23. Tazawa, M., M. Kikuyama andT. Shimmen. 1976. Electric characteristics and cytoplasmic streaming of Characeae cells lacking tonoplast. Cell Structure Function1: 165–176.CrossRefGoogle Scholar
  24. Terakawa, S. andA. Watanabe. 1976. Effects of intracellular pH on plateau formation following the action potential of squid giant axons. Jap. J. Physiol.26: 693–701.Google Scholar
  25. Walker, N.A. andF.A. Smith. 1975. Intracellular pH inChara corallina measured by DMO distribution. Plant Sci. Lett.4: 125–132.CrossRefGoogle Scholar

Copyright information

© The Botanical Society of Japan 1982

Authors and Affiliations

  • Masashi Tazawa
    • 1
  • Teruo Shimmen
    • 1
  1. 1.Department of Botany, Faculty of ScienceUniversity of TokyoTokyo

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