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Planta. 1981 May;152(1):59-69. doi: 10.1007/BF00384986.

Changes in glucan synthetase activity and plasma membrane proteins during encystment of the cellular slime mold Polysphondylium pallidum.

Planta

M L Philippi, R W Parish

Affiliations

  1. Cytology, Plant Biology Institute, University of Zürich, Zollikerstraße 107, CH-8008, Zürich, Switzerland.

PMID: 24302320 DOI: 10.1007/BF00384986

Abstract

The activity of glucan synthetase increased dramatically during encystment of Polysphondylium pallidum cells. The majority of activity was present in purified plasma membranes. Activity, measured as glucose incorporation from UDPG into NaOH-insoluble glucan, increased 30-40 fold in the membranes. Increases in activity within the cells preceded plasma membrane increases and the enzyme appeared to be rapidly transported to the plasma membrane. Intracellular activity was relatively low. When cells were incubated with UDPG and when phloretin was included to inhibit glucose uptake, no NaOH-insoluble glucan was synthesized. Hence, the UDPG-binding site was not exposed at the cell-surface. When the NaOH-insoluble glucan was digested with endo-β-1,4-glucanase the products were cellobiose and glucose. The glucan could also be precipitated from Schweizer's reagent with acetic acid. These results suggest that the glucan contained predominantly β-1,4-linkages and may be cellulose. Experiments with cycloheximide confirmed that protein synthesis was required for encystment. Labeling of cells with [1-(14)C]-acetate showed that the synthesis of certain plasma membrane proteins was developmentally regulated. A number of proteins (e.g., myosin heavy chains and actin) were synthesized during the lag phase and their synthesis was subsequently reduced or ceased altogether. Immediately prior to the commencement of cyst wall formation seven new plasma membrane proteins were synthesized. These proteins were not detected intracellularly, indicating rapid transfer to the plasma membrane. The possible relationship between the seven developmentally regulated proteins and a postulated "multi-enzyme-complex" involved in cellulose synthesis is discussed. Their synthesis may be related to the increase in particles in the outer leaflet of the plasma membrane observed during encystment with freeze-etching (G.W. Erdos and H.R. Hohl, 1980, Cytobios, 29, 7-16).

References

  1. Science. 1974 Oct 25;186(4161):357-9 - PubMed
  2. J Bacteriol. 1973 Jan;113(1):192-7 - PubMed
  3. Naturwissenschaften. 1968 Dec;55(12):656 - PubMed
  4. Exp Cell Res. 1977 Dec;110(2):267-76 - PubMed
  5. FEBS Lett. 1979 Dec 1;108(1):219-25 - PubMed
  6. J Cell Sci. 1970 Jul;7(1):285-305 - PubMed
  7. Plant Physiol. 1974 Sep;54(3):333-40 - PubMed
  8. FEBS Lett. 1976 Mar 15;63(1):40-41 - PubMed
  9. J Bacteriol. 1967 Oct;94(4):1143-9 - PubMed
  10. J Cell Biol. 1975 Mar;64(3):557-71 - PubMed
  11. J Cell Biol. 1980 Feb;84(2):327-39 - PubMed
  12. Plant Physiol. 1978 Jun;61(6):938-42 - PubMed
  13. FEBS Lett. 1980 Sep 8;118(2):263-6 - PubMed
  14. Plant Physiol. 1975 Jul;56(1):34-8 - PubMed
  15. Nature. 1970 Aug 15;227(5259):680-5 - PubMed
  16. Biochim Biophys Acta. 1976 Oct 22;444(3):802-9 - PubMed
  17. J Cell Biol. 1980 Feb;84(2):315-26 - PubMed
  18. FEBS Lett. 1979 Feb 15;98(2):251-6 - PubMed
  19. Planta. 1977 Jan;136(2):135-45 - PubMed
  20. Cytobios. 1980;29(113):7-16 - PubMed
  21. Science. 1963 Jan 25;139(3552):338 - PubMed
  22. Proc Natl Acad Sci U S A. 1969 Oct;64(2):605-12 - PubMed
  23. J Bacteriol. 1967 Oct;94(4):1150-3 - PubMed
  24. Exp Cell Res. 1981 Jan;131(1):89-96 - PubMed
  25. Proc Natl Acad Sci U S A. 1971 Sep;68(9):2052-6 - PubMed
  26. Plant Physiol. 1977 Apr;59(4):719-23 - PubMed
  27. Plant Physiol. 1977 Apr;59(4):594-9 - PubMed
  28. Int Rev Cytol. 1973;36:45-92 - PubMed
  29. Plant Physiol. 1977 Apr;59(4):713-8 - PubMed
  30. Proc Natl Acad Sci U S A. 1976 Jan;73(1):143-7 - PubMed
  31. J Cell Biol. 1970 May;45(2):246-71 - PubMed
  32. Plant Physiol. 1978 May;61(5):723-30 - PubMed
  33. Proc Natl Acad Sci U S A. 1975 May;72(5):1758-62 - PubMed
  34. Biochim Biophys Acta. 1971 Apr 20;237(1):65-74 - PubMed
  35. Plant Physiol. 1978 Jun;61(6):943-8 - PubMed
  36. Dev Biol. 1976 Oct 1;53(1):62-72 - PubMed
  37. J Supramol Struct. 1976;5(3):277-90 - PubMed
  38. J Cell Biol. 1978 Apr;77(1):103-19 - PubMed
  39. Proc Natl Acad Sci U S A. 1976 Dec;73(12):4570-4 - PubMed

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