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Absence of an intracellular pH change following fertilisation of the mouse egg

Published online by Cambridge University Press:  26 September 2008

Douglas Kline*
Affiliation:
Department of Biological Sciences, Kent State University, Kent, Ohio, USA.
James A. Zagray
Affiliation:
Department of Biological Sciences, Kent State University, Kent, Ohio, USA.
*
Douglas Kline, Department of Biological Sciences, Kent State University, Kent, OH 44242, USA. Telephone: 216 672-3810. Fax: 216 672-3713. e-mail: dkline@kentvm.kent.edu.

Summary

The intracellular pH of the mouse egg was measured during fertilisation to determine whether an increase in pH accompanies activation of this mammalian egg. The pH-sensitive dye BCECF [2′,7′-bis-(2-carboxyethyl)-5(and-6)carboxyfluorescein] was introduced into the mouse egg by incubation in BCECF-AM or by microinjection of dextran-conjugated BCECF. The cells were also loaded with the DNA-specific fluorochrome Hoechst 33342 to confirm fertilisation by observation of Hoechst-stained, decondensing sperm heads in the cytoplasm. The ratio of emission intensities for the dye (494/440 nm excitation wavelengths) was monitored continuously with a photon-counting photomultiplier tube. There was no change in pH during or after fertilisation. Control eggs displayed the expected increase in pH when exposed to NH4C1. In other experiments, intracellular pH and intracellular Ca2+ were monitored simultaneously during fertilisation. The eggs were injected with BCECF dextran and Fura dextran. Fluorescence emission was recorded at excitation wavelengths of 495 nm (BCECF, pH-sensitive wavelength) and 385 nm (Fura, Ca2+-sensitive wavelength). A decrease in emission intensity at 385 nm excitation clearly marked the repetitive Ca2+ transients at egg activation. There was no change in the fluorescence emitted at 495 nm excitation, indicating an absence of any change in intracellular pH. These results indicate that intracellular alkalinisation of the cytoplasm does not accompany activation of this vertebrate egg.

Type
Article
Copyright
Copyright © Cambridge University Press 1995

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References

Referances

Baltz, J.M., Biggers, J.D., & Lechene, C. (1990). Apparent absence of Na+/H+ antiport activity in the two-cell mouse embryo, Dev. Biol. 138 421–9.Google Scholar
Baltz, J.M., Biggers, J.D. & Lechene, C. (1991). Two-cell mouse embryos appear to lack mechanisms for alleviating intracellulr acid loads. J. Biol. Chem. 266, 6052–7.Google Scholar
Busa, W.B., & Nuccitelli, R. (1984). Metabolic regulation via intracellular pH Am. J. Physiol. 246, R409–38.Google Scholar
Depypere, H.T., & Leybaert, L. (1994). Intracellular pH changes during zona drilling. Fertil. Steril. 61, 319–23.Google Scholar
Dubé, F. (1988). The relationships between early ionic events, the pattern of protein synthesis, and oocyte activation in the surf clam, Spisula solidissima. Dev. Biol. 126 233–41.Google Scholar
Dubé, F., & Guerrier, P. (1982). Acid release during activation of Barnea candida (Mollusca, Pelecypoda) oocytes Dev. Growth Differ. 24 163–71.CrossRefGoogle ScholarPubMed
Epel, D. (1989). Arousal of activity in sea urchin eggs at fertilization. In The Cell Biology of Fetilization, ed. Schatten, H. & Schatten, G., pp. 361–85. New York: Academic press.CrossRefGoogle Scholar
Freeman, G., & Ridgway, E.B. (1993). The role of intracellular calcium and pH during fertilization and egg activation in the hydrozoan Phialidium. Dev. Biol. 156, 176–90.Google Scholar
Gibbon, B.C., & Kropf, D.L. (1993) Intracellular pH and its regulation in Pelvetia zygotes, Dev. Biol., 157, 259–68.Google Scholar
Gould, M.C., & Stephano, J.L. (1993). Nucler and cytoplasmic pH increase at fertilization in Urechis caupo. Dev. Biol. 159 608–17.Google Scholar
Grainger, J.L., Winkler, M.M., Shen, S.S., & Steinhardt, R.A. (1979). Intracellular pH controls protein synthesis rate in the sea urchin egg and early embryo. Dev. Biol. 68 396406.CrossRefGoogle ScholarPubMed
Grandin, N. & Charbonneau, M. (1989). Intracellular pH and the increase in protein synthesis accompanying activation of Xenopus eggs. Biol. Cell 67, 321–30.CrossRefGoogle ScholarPubMed
Grandin, N., Rolland, J-P., & Charbonneau, M. (1991). Changes in intracellular pH following egg activition and during the early cell cycle of the amphibian Pleurodeles waltlii coincide with changes in MPF activity Biol. Cell. 72 259–67.CrossRefGoogle Scholar
Hamaguchi, M.S. (1982). The role of intracellular pH in fetilization of sand dollar eggs analyzed by micro-injection method, Dev. Growth Differ. 24 443–51.CrossRefGoogle Scholar
Hervé, M., Goudeau, M., Neumann, J.M., Debouzy, J.C., & Goudeau, H. (1989). Measurement of an intracellular pH rise after fertilization in crab eggs using 31P-NMR. Eur. Biophys. J. 17 191–9.CrossRefGoogle ScholarPubMed
Hiramoto, Y. (1984). Micromanipulation. Cell struct. Funct. 9 (supply), s139–44.CrossRefGoogle ScholarPubMed
House, C.R. (1994) Confocal ration-imaging of intracellular pH in unfertilised mouse oocytes Zygote, 2, 3745.Google Scholar
Iwamatsu, T. (1984). Effects of pH on the fertiliztion response of the medaka egg Dev. Growth Differ. 26 533–44.Google Scholar
Johnson, C.H., & Epel, D. (1981). Intracellular PH of sea urchin eggs measured by the dimethyloxazolidinedione(DMO) method J. cell. Biol. 89 284–91.Google Scholar
Johnson, C.H. & Epel, D. (1982). Starfish oocyte maturation and fertilization: intracellular pH is not involved in activation Dev. Biol. 92 461–9.Google Scholar
Kline, D. & kline, J.T. (1992a). Repetitive calcium transients and the role of calcium in exocytosis and cell cycle activation in the mouse egg. Dev. Biol. 149 80–9.Google Scholar
Kline, D, & Kline, J.T. (1992b). Thapsigargin activete a calcium influx pathway in the unfertilized mouse egg and suppresses repetitive calcium transients in the fertilized egg J. Biol. Chem. 267. 17624–30.Google Scholar
Lee, S.C. & Steinhardt, R.A. (1981). pH changes associated with meitoic maturation in oocytes of Xenopus laevis. Dev. Biol. 85 358–96.CrossRefGoogle Scholar
Mazia, D., & Ruby, A. (1974). DNA synthesis turned on in unfertilized sea urchin eggs by treatment with NH4OH Exp. Cell Res. 85 167–72.CrossRefGoogle ScholarPubMed
Mehlmann, L.M. & Kline, D. (1994). Regulation of intracellular calcium in the mouse egg: calcium release in response to sperm or inositol trisphospate is enchanced after meiotic maturation. Biol. Reprod. 51 1088–98.CrossRefGoogle ScholarPubMed
Nuccitelli, R., Webb, D.J., Lagier, S.T., & Matson, G.B. (1981). 31P NMR reveals increased intracellular pH after fertilization in Xenopus eggs.. Proc. Natl. Acad. Sci. USA 78, 4421–5.CrossRefGoogle ScholarPubMed
Paul, M. (1975). Release of acid and changes in light-scattering properties following fertilization of Urechis caupo eggs Dev. Biol. 43 299312.Google Scholar
Payan, P., Girard, J. & Ciapa, B. (1983). Mechanisms regulating intracellular pH in sea urchin eggs. Dev. Biol. 100 2938.Google Scholar
Peaucellier, G. (1978). Acid release at meiotic maturation of oocytes in the polychaete annelid Sabellaria alveolata. Experientia 34,789–90.Google Scholar
Peaucellier, G., & Doree, M. (1981). Acid release at activation and fertilization of starfish oocytes. Dev. Growth Differ. 23, 287–96.CrossRefGoogle ScholarPubMed
Peaucellier, G., Picard, A., Robert, J., Capony, J.Labbe, J. & Doree, M. (1988). Phosphorylation of ribosomal proteins during meiotic maturation and following activation in starfish oocytes: its relationship with changes of intracellular pH Exp. cell Res. 174, 7188.Google Scholar
Rees, B.B., Patton, C., Grainger, J.L. & Epel, D. (1995). Protein synthesis increases after fertilization of sea urchin eggs in the absence of an increase in intracellular pH. Dev. Biol. 169 683–98.CrossRefGoogle ScholarPubMed
Russo, P., Pecorella, M.A., De Santis, A. & Dale, B. (1989) pH in eggs of the ascidian Ciona intestinalis at fertilization and activation J. Exp. Zool 250 329–32.Google Scholar
Schutz, R.M., Letourneau, G.E., & Wassarman, P.M. (1979). Program of early development in the mammal: changes in patterns and absolute rates of tubulin and total protein synthesis during oogenesis and early embryogenesis in the mouse. Dev. Biol. 68 341–59.CrossRefGoogle Scholar
Shen, S.S., & Steinhardt, R.A. (1978). Direct measurement of intracellular pH during metabolic derepression of the sea urchin egg Nature 272 253–4.Google Scholar
Shen, S.S. & Steinhardt, R.A. (1980) Intracellular pH controls the development of new potassium conductance after fertilization of the sea urchin egg. Exp. Cell Res. 125 5561.CrossRefGoogle ScholarPubMed
Thomas, R.C. (1984) Experimental displacement of intracellular pH and the mechanism of its subsequent recovery. J. Physiol. (Lond.) 354 pp. 3P–22P.Google Scholar
Webb, D.J., & Nuccitelli, R. (1981). Direct measurement of intracellular pH changes in Xenopus eggs at fertilization and cleavage. J. Cell Biol. 91 562–7.CrossRefGoogle ScholarPubMed
Whitaker, M.J. & Steinhardt, R.A. (1985). Ionic signaling in the sea urchin egg at fertilization In Biology of Fertilization, ed. Metz, C.B. & Monroy, A., vol. 3, pp. 167221New York: Academic Press.CrossRefGoogle Scholar
Winkler, M.M., & Grainger, J.L. (1978). Mechanism of action of NH4CL and other weak bases in the activation of sea urchin eggs Nature 273 536–8.Google Scholar
Winkler, M.M., Steinhardt, R.A., Grainger, J.L. & Minning, L. (1980). Dual ionic controls for the activation of protein synthesis at fertilization Nature 287, 558–60.Google Scholar
Winkler, M.M., Matson, G.B., Hershey, J.W.B. & Bradbury, E.M. (1983). 32P-NMR study of the activation of the sea urchin egg. Exp. Cell Res. 139, 217–22.Google Scholar