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Plant Physiol. Nov 1991; 97(3): 1241–1248.
PMCID: PMC1081148

Hydrolysis of Polyphosphates and Permeability Changes in Response to Osmotic Shocks in Cells of the Halotolerant Alga Dunaliella


The effects of osmotic shocks on polyphosphates and on the vacuolar fluorescent indicator atebrin have been investigated to test whether acidic vacuoles in the halotolerant alga Dunaliella salina have a role in osmoregulation. Upshocks and downshocks induce different patterns of polyphosphate hydrolysis. Upshocks induce rapid formation of new components, tentatively identified as 5 or 6 linear polyphosphates, formed only after upshocks with NaCl and not with glycerol, indicative of compartmentation of Na+ into the vacuoles. Conversely, downshocks induce a slower transient accumulation of tripolyphosphates, indicating activation of a different hydrolytic process within the vacuoles. Osmotic shocks do not lead to release of atebrin from acidic vacuoles, indicating that they do not induce a major intravacuolar alkalinization. However, osmotic shocks induce transient permeability changes measured by amine-induced atebrin release from vacuoles. Hypoosmotic shocks transiently increase the permeability (up to 20-fold), whereas hyperosmotic shocks induce a rapid drop in permeability. Electron micrographs of osmotically shocked cells also reveal transient changes in the surface and internal organelles of D. salina cells. It is suggested that hyperosmotic and hypoosmotic shocks induce different changes within acidic vacuoles and in the organization and/or composition of the plasma membrane in Dunaliella.

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  • Bental M, Pick U, Avron M, Degani H. Metabolic studies with NMR spectroscopy of the alga Dunaliella salina trapped within agarose beads. Eur J Biochem. 1990 Feb 22;188(1):111–116. [PubMed]
  • Bental M, Pick U, Avron M, Degani H. Polyphosphate metabolism in the alga Dunaliella salina studied by 31P-NMR. Biochim Biophys Acta. 1991 Mar 19;1092(1):21–28. [PubMed]
  • Brown FF, Sussman I, Avron M, Degani H. [NMR studies of glycerol permeability in lipid vesicles, erythrocytes and the alga Dunaliella]. Biochim Biophys Acta. 1982 Sep 9;690(2):165–173. [PubMed]
  • Chitlaru E, Pick U. Selection and Characterization of Dunaliella salina Mutants Defective in Haloadaptation. Plant Physiol. 1989 Oct;91(2):788–794. [PMC free article] [PubMed]
  • Curtain CC, Looney FD, Regan DL, Ivancic NM. Changes in the ordering of lipids in the membrane of Dunaliella in response to osmotic-pressure changes. An e.s.r. study. Biochem J. 1983 Jul 1;213(1):131–136. [PMC free article] [PubMed]
  • Einspahr KJ, Peeler TC, Thompson GA., Jr Rapid changes in polyphosphoinositide metabolism associated with the response of Dunaliella salina to hypoosmotic shock. J Biol Chem. 1988 Apr 25;263(12):5775–5779. [PubMed]
  • Garbarino J, Dupont FM. NaCl Induces a Na/H Antiport in Tonoplast Vesicles from Barley Roots. Plant Physiol. 1988 Jan;86(1):231–236. [PMC free article] [PubMed]
  • Klut ME, Stockner J, Bisalputra T. Further use of fluorochromes in the cytochemical characterization of phytoplankton. Histochem J. 1989 Nov;21(11):645–650. [PubMed]
  • Maeda M, Thompson GA., Jr On the mechanism of rapid plasma membrane and chloroplast envelope expansion in Dunaliella salina exposed to hypoosmotic shock. J Cell Biol. 1986 Jan;102(1):289–297. [PMC free article] [PubMed]
  • Pick U, Karni L, Avron M. Determination of Ion Content and Ion Fluxes in the Halotolerant Alga Dunaliella salina. Plant Physiol. 1986 May;81(1):92–96. [PMC free article] [PubMed]
  • Pick U, Zeelon O, Weiss M. Amine Accumulation in Acidic Vacuoles Protects the Halotolerant Alga Dunaliella salina Against Alkaline Stress. Plant Physiol. 1991 Nov;97(3):1226–1233. [PMC free article] [PubMed]
  • Pick U, Weiss M. Polyphosphate Hydrolysis within Acidic Vacuoles in Response to Amine-Induced Alkaline Stress in the Halotolerant Alga Dunaliella salina. Plant Physiol. 1991 Nov;97(3):1234–1240. [PMC free article] [PubMed]
  • Weisman LS, Bacallao R, Wickner W. Multiple methods of visualizing the yeast vacuole permit evaluation of its morphology and inheritance during the cell cycle. J Cell Biol. 1987 Oct;105(4):1539–1547. [PMC free article] [PubMed]

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