Abstract
Pyranine was employed as a sensitive pH indicator in a low light level microspectrofluorometer. The in vivo and in vitro standard curves of the 460/410-nm fluorescence excitation ratio of pyranine as a function of pH are identical. Therefore, pyranine is specifically sensitive to cytoplasmic pH in Dictyostelium. The cytoplasmic pH of single cells in a population of Dictyostelium discoideum amoebae was obtained for the first time. The median cytoplasmic pH of vegetative amoebae was 7.19. Carbonyl cyanide m-chlorophenylhydrazone, a mitochondrial uncoupler and a protonophore, lowered the median cytoplasmic pH to 6.12 when the extracellular pH was 6.1. This result is in accord with the protonophore activity of carbonyl cyanide m-chlorophenylhydrazone. Interest in the cytoplasmic pH of Dictyostelium has been greatly stimulated by the theory that cytoplasmic acidification promotes development of pre-stalk cells, while cytoplasmic alkalinization favors the pre-spore pathway (Gross, J. D., J. Bradbury, R. R. Kay, M. J. Peacey. 1983. Nature (Lond.). 303:244-245). The theory postulates that diethylstilbestrol (DES), an inducer of stalk cell differentiation and a plasma membrane proton translocating ATPase inhibitor, should cause acidification of the cytosol. Previous measurements of the effects of stalk cell inducers including DES on intracellular pH using 31P nuclear magnetic resonance measurements have failed to confirm the predictions of the theory, and have suggested that significant modification of the model may be required. Using pyranine as the pH indicator, we find that the median cytoplasmic pH in cells treated with 10 microM DES dropped from 7.19 to pH 6.02. This effect is consistent with the pharmacological action of DES and with the proposal that DES, a stalk cell inducer, should acidify the cytosol. These results provide direct support for the theory that cytoplasmic pH is an essential regulator of the developmental pathway in Dictyostelium.
Full Text
The Full Text of this article is available as a PDF (1.2 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aerts R. J. Changes in cytoplasmic pH are involved in the cell type regulation of Dictyostelium. Cell Differ. 1988 Mar;23(1-2):125–131. doi: 10.1016/0045-6039(88)90044-9. [DOI] [PubMed] [Google Scholar]
- Aerts R. J., Durston A. J., Konijn T. M. Cytoplasmic pH at the onset of development in Dictyostelium. J Cell Sci. 1987 Apr;87(Pt 3):423–430. doi: 10.1242/jcs.87.3.423. [DOI] [PubMed] [Google Scholar]
- Aerts R. J., Durston A. J., Moolenaar W. H. Cytoplasmic pH and the regulation of the Dictyostelium cell cycle. Cell. 1985 Dec;43(3 Pt 2):653–657. doi: 10.1016/0092-8674(85)90237-5. [DOI] [PubMed] [Google Scholar]
- Bowman B. J., Mainzer S. E., Allen K. E., Slayman C. W. Effects of inhibitors on the plasma membrane and mitochondrial adenosine triphosphatases of Neurospora crassa. Biochim Biophys Acta. 1978 Sep 11;512(1):13–28. doi: 10.1016/0005-2736(78)90214-6. [DOI] [PubMed] [Google Scholar]
- Bright G. R., Fisher G. W., Rogowska J., Taylor D. L. Fluorescence ratio imaging microscopy: temporal and spatial measurements of cytoplasmic pH. J Cell Biol. 1987 Apr;104(4):1019–1033. doi: 10.1083/jcb.104.4.1019. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Busa W. B., Nuccitelli R. Metabolic regulation via intracellular pH. Am J Physiol. 1984 Apr;246(4 Pt 2):R409–R438. doi: 10.1152/ajpregu.1984.246.4.R409. [DOI] [PubMed] [Google Scholar]
- Condeelis J. S., Taylor D. L. The contractile basis of amoeboid movement. V. The control of gelation, solation, and contraction in extracts from Dictyostelium discoideum. J Cell Biol. 1977 Sep;74(3):901–927. doi: 10.1083/jcb.74.3.901. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fechheimer M., Denny C., Murphy R. F., Taylor D. L. Measurement of cytoplasmic pH in Dictyostelium discoideum by using a new method for introducing macromolecules into living cells. Eur J Cell Biol. 1986 Apr;40(2):242–247. [PubMed] [Google Scholar]
- Fechheimer M., Taylor D. L. Introduction of exogenous molecules into the cytoplasm of Dictyostelium discoideum amoebae by controlled sonication. Methods Cell Biol. 1987;28:179–190. doi: 10.1016/s0091-679x(08)61644-1. [DOI] [PubMed] [Google Scholar]
- Giuliano K. A., Gillies R. J. Determination of intracellular pH of BALB/c-3T3 cells using the fluorescence of pyranine. Anal Biochem. 1987 Dec;167(2):362–371. doi: 10.1016/0003-2697(87)90178-3. [DOI] [PubMed] [Google Scholar]
- Gomer R. H., Firtel R. A. Cell-autonomous determination of cell-type choice in Dictyostelium development by cell-cycle phase. Science. 1987 Aug 14;237(4816):758–762. doi: 10.1126/science.3039657. [DOI] [PubMed] [Google Scholar]
- Gross J. D., Bradbury J., Kay R. R., Peacey M. J. Intracellular pH and the control of cell differentiation in Dictyostelium discoideum. Nature. 1983 May 19;303(5914):244–245. doi: 10.1038/303244a0. [DOI] [PubMed] [Google Scholar]
- Heiple J. M., Taylor D. L. Intracellular pH in single motile cells. J Cell Biol. 1980 Sep;86(3):885–890. doi: 10.1083/jcb.86.3.885. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Inouye K. Measurements of intracellular pH and its relevance to cell differentiation in Dictyostelium discoideum. J Cell Sci. 1985 Jun;76:235–245. doi: 10.1242/jcs.76.1.235. [DOI] [PubMed] [Google Scholar]
- Jamieson G. A., Jr, Frazier W. A., Schlesinger P. H. Transient increase in intracellular pH during Dictyostelium differentiation. J Cell Biol. 1984 Nov;99(5):1883–1887. doi: 10.1083/jcb.99.5.1883. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jentoft J. E., Town C. D. Intracellular pH in Dictyostelium discoideum: a 31P nuclear magnetic resonance study. J Cell Biol. 1985 Sep;101(3):778–784. doi: 10.1083/jcb.101.3.778. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kay R. R., Gadian D. G., Williams S. R. Intracellular pH in Dictyostelium: a 31P nuclear magnetic resonance study of its regulation and possible role in controlling cell differentiation. J Cell Sci. 1986 Jul;83:165–179. doi: 10.1242/jcs.83.1.165. [DOI] [PubMed] [Google Scholar]
- Liberman E. A., Topaly V. P. Selective transport of ions through bimolecular phospholipid membranes. Biochim Biophys Acta. 1968 Sep 17;163(2):125–136. doi: 10.1016/0005-2736(68)90089-8. [DOI] [PubMed] [Google Scholar]
- Loomis W. F., Jr Sensitivity of Dictyostelium discoideum to nucleic acid analogues. Exp Cell Res. 1971 Feb;64(2):484–486. doi: 10.1016/0014-4827(71)90107-8. [DOI] [PubMed] [Google Scholar]
- Marin F. T. Regulation of development in Dictyostelium discoideum: I. Initiation of the growth to development transition by amino acid starvation. Dev Biol. 1976 Jan;48(1):110–117. doi: 10.1016/0012-1606(76)90050-6. [DOI] [PubMed] [Google Scholar]
- Martin J. B., Foray M. F., Klein G., Satre M. Identification of inositol hexaphosphate in 31P-NMR spectra of Dictyostelium discoideum amoebae. Relevance to intracellular pH determination. Biochim Biophys Acta. 1987 Oct 22;931(1):16–25. doi: 10.1016/0167-4889(87)90045-0. [DOI] [PubMed] [Google Scholar]
- Pollard H. B., Shindo H., Creutz C. E., Pazoles C. J., Cohen J. S. Internal pH and state of ATP in adrenergic chromaffin granules determined by 31P nuclear magnetic resonance spectroscopy. J Biol Chem. 1979 Feb 25;254(4):1170–1177. [PubMed] [Google Scholar]
- Rich E. S., Jr, Wampler J. E. A flexible, computer-controlled video microscope capable of quantitative spatial, temporal, and spectral measurements. Clin Chem. 1981 Sep;27(9):1558–1568. [PubMed] [Google Scholar]
- Roos A., Boron W. F. Intracellular pH. Physiol Rev. 1981 Apr;61(2):296–434. doi: 10.1152/physrev.1981.61.2.296. [DOI] [PubMed] [Google Scholar]
- Satre M., Klein G., Martin J. B. Intracellular pH control in Dictyostelium discoideum: a 31P-NMR analysis. Biochimie. 1986 Dec;68(12):1253–1261. doi: 10.1016/s0300-9084(86)80077-3. [DOI] [PubMed] [Google Scholar]
- Satre M., Martin J. B. 31P-nuclear magnetic resonance analysis of the intracellular pH in the slime mold Dictyostelium discoideum. Biochem Biophys Res Commun. 1985 Oct 15;132(1):140–146. doi: 10.1016/0006-291x(85)90999-4. [DOI] [PubMed] [Google Scholar]
- Schindler J., Sussman M. Ammonia determines the choice of morphogenetic pathways in Dictyostelium discoideum. J Mol Biol. 1977 Oct 15;116(1):161–169. doi: 10.1016/0022-2836(77)90124-3. [DOI] [PubMed] [Google Scholar]
- Steinberg T. H., Newman A. S., Swanson J. A., Silverstein S. C. Macrophages possess probenecid-inhibitable organic anion transporters that remove fluorescent dyes from the cytoplasmic matrix. J Cell Biol. 1987 Dec;105(6 Pt 1):2695–2702. doi: 10.1083/jcb.105.6.2695. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Taylor D. L., Fechheimer M. Cytoplasmic structure and contractility: the solation--contraction coupling hypothesis. Philos Trans R Soc Lond B Biol Sci. 1982 Nov 4;299(1095):185–197. doi: 10.1098/rstb.1982.0125. [DOI] [PubMed] [Google Scholar]
- Town C. D., Dominov J. A., Karpinski B. A., Jentoft J. E. Relationships between extracellular pH, intracellular pH, and gene expression in Dictyostelium discoideum. Dev Biol. 1987 Aug;122(2):354–362. doi: 10.1016/0012-1606(87)90300-9. [DOI] [PubMed] [Google Scholar]
- Williams G. B., Elder E. M., Sussman M. Modulation of the cAMP relay in Dictyostelium discoideum by ammonia and other metabolites: possible morphogenetic consequences. Dev Biol. 1984 Oct;105(2):377–388. doi: 10.1016/0012-1606(84)90294-x. [DOI] [PubMed] [Google Scholar]
