Skip to main content
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1984 Sep 1;99(3):844–851. doi: 10.1083/jcb.99.3.844

A 45,000-mol-wt protein from unfertilized sea urchin eggs severs actin filaments in a calcium-dependent manner and increases the steady-state concentration of nonfilamentous actin

PMCID: PMC2113406  PMID: 6540784

Abstract

A 45,000-mol-wt protein has been purified from unfertilized sea urchin (Strongylocentrotus purpuratus) eggs. The isolation scheme includes DEAE cellulose ion-exchange chromatography, gel filtration, and hydroxylapatite chromatography. The homogeneity of the isolated protein is greater than 90% by SDS PAGE. The 45,000-mol-wt protein reduces the viscosity of actin filaments in a Ca2+-dependent manner. The free calcium concentration required for the activity of this protein is in the micromolar range. Electron microscopic studies reveal that the formation of short filaments parallels the decrease in viscosity. Energy transfer and sedimentation experiments indicate a net disassembly of actin filaments and an increase in the steady-state nonfilamentous actin concentration in the presence of Ca2+ ions and the 45,000-mol-wt protein. The increase in the steady-state nonfilamentous actin concentration is proportional to the amount of 45,000-mol-wt protein added. The actin molecules disassembled by the addition of the 45,000-mol-wt protein are capable of polymerization.

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.

  1. Begg D. A., Rebhun L. I., Hyatt H. Structural organization of actin in the sea urchin egg cortex: microvillar elongation in the absence of actin filament bundle formation. J Cell Biol. 1982 Apr;93(1):24–32. doi: 10.1083/jcb.93.1.24. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bonder E. M., Fishkind D. J., Mooseker M. S. Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament. Cell. 1983 Sep;34(2):491–501. doi: 10.1016/0092-8674(83)90382-3. [DOI] [PubMed] [Google Scholar]
  3. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  4. Brown S. S., Yamamoto K., Spudich J. A. A 40,000-dalton protein from Dictyostelium discoideum affects assembly properties of actin in a Ca2+-dependent manner. J Cell Biol. 1982 Apr;93(1):205–210. doi: 10.1083/jcb.93.1.205. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bryan J., Kane R. E. Separation and interaction of the major components of sea urchin actin gel. J Mol Biol. 1978 Oct 25;125(2):207–224. doi: 10.1016/0022-2836(78)90345-5. [DOI] [PubMed] [Google Scholar]
  6. Burgess D. R., Schroeder T. E. Polarized bundles of actin filaments within microvilli of fertilized sea urchin eggs. J Cell Biol. 1977 Sep;74(3):1032–1037. doi: 10.1083/jcb.74.3.1032. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Carlsson L., Nyström L. E., Sundkvist I., Markey F., Lindberg U. Actin polymerizability is influenced by profilin, a low molecular weight protein in non-muscle cells. J Mol Biol. 1977 Sep 25;115(3):465–483. doi: 10.1016/0022-2836(77)90166-8. [DOI] [PubMed] [Google Scholar]
  8. Chandler D. E., Heuser J. Postfertilization growth of microvilli in the sea urchin egg: new views from eggs that have been quick-frozen, freeze-fractured, and deeply etched. Dev Biol. 1981 Mar;82(2):393–400. doi: 10.1016/0012-1606(81)90463-2. [DOI] [PubMed] [Google Scholar]
  9. Eddy E. M., Shapiro B. M. Changes in the topography of the sea urchin egg after fertilization. J Cell Biol. 1976 Oct;71(1):35–48. doi: 10.1083/jcb.71.1.35. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Epel D. Mechanisms of activation of sperm and egg during fertilization of sea urchin gametes. Curr Top Dev Biol. 1978;12:185–246. doi: 10.1016/s0070-2153(08)60597-9. [DOI] [PubMed] [Google Scholar]
  11. Giffard R. G., Weeds A. G., Spudich J. A. Ca2+-dependent binding of severin to actin: a one-to-one complex is formed. J Cell Biol. 1984 May;98(5):1796–1803. doi: 10.1083/jcb.98.5.1796. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Harafuji H., Ogawa Y. Re-examination of the apparent binding constant of ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid with calcium around neutral pH. J Biochem. 1980 May;87(5):1305–1312. doi: 10.1093/oxfordjournals.jbchem.a132868. [DOI] [PubMed] [Google Scholar]
  13. Hartree E. F. Determination of protein: a modification of the Lowry method that gives a linear photometric response. Anal Biochem. 1972 Aug;48(2):422–427. doi: 10.1016/0003-2697(72)90094-2. [DOI] [PubMed] [Google Scholar]
  14. Hosoya H., Mabuchi I., Sakai H. Actin modulating proteins in the sea urchin egg. I. Analysis of G-actin-binding proteins by DNase I-affinity chromatography and purification of a 17,000 molecular weight component. J Biochem. 1982 Dec;92(6):1853–1862. doi: 10.1093/oxfordjournals.jbchem.a134115. [DOI] [PubMed] [Google Scholar]
  15. Houk T. W., Jr, Ue K. The measurement of actin concentration in solution: a comparison of methods. Anal Biochem. 1974 Nov;62(1):66–74. doi: 10.1016/0003-2697(74)90367-4. [DOI] [PubMed] [Google Scholar]
  16. Kane R. E. Actin polymerization and interaction with other proteins in temperature-induced gelation of sea urchin egg extracts. J Cell Biol. 1976 Dec;71(3):704–714. doi: 10.1083/jcb.71.3.704. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kane R. E. Preparation and purification of polymerized actin from sea urchin egg extracts. J Cell Biol. 1975 Aug;66(2):305–315. doi: 10.1083/jcb.66.2.305. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Korn E. D. Actin polymerization and its regulation by proteins from nonmuscle cells. Physiol Rev. 1982 Apr;62(2):672–737. doi: 10.1152/physrev.1982.62.2.672. [DOI] [PubMed] [Google Scholar]
  19. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  20. Mabuchi I. An actin-depolymerizing protein (depactin) from starfish oocytes: properties and interaction with actin. J Cell Biol. 1983 Nov;97(5 Pt 1):1612–1621. doi: 10.1083/jcb.97.5.1612. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Mabuchi I., Spudich J. A. Purification and properties of soluble actin from sea urchin eggs. J Biochem. 1980 Mar;87(3):785–802. doi: 10.1093/oxfordjournals.jbchem.a132808. [DOI] [PubMed] [Google Scholar]
  22. Otto J. J., Kane R. E., Bryan J. Formation of filopodia in coelomocytes: localization of fascin, a 58,000 dalton actin cross-linking protein. Cell. 1979 Jun;17(2):285–293. doi: 10.1016/0092-8674(79)90154-5. [DOI] [PubMed] [Google Scholar]
  23. Otto J. J., Kane R. E., Bryan J. Redistribution of actin and fascin in sea urchin eggs after fertilization. Cell Motil. 1980;1(1):31–40. doi: 10.1002/cm.970010104. [DOI] [PubMed] [Google Scholar]
  24. Pardee J. D., Simpson P. A., Stryer L., Spudich J. A. Actin filaments undergo limited subunit exchange in physiological salt conditions. J Cell Biol. 1982 Aug;94(2):316–324. doi: 10.1083/jcb.94.2.316. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Pardee J. D., Spudich J. A. Purification of muscle actin. Methods Enzymol. 1982;85(Pt B):164–181. doi: 10.1016/0076-6879(82)85020-9. [DOI] [PubMed] [Google Scholar]
  26. Pollard T. D. A falling ball apparatus to measure filament cross-linking. Methods Cell Biol. 1982;24:301–311. doi: 10.1016/s0091-679x(08)60663-9. [DOI] [PubMed] [Google Scholar]
  27. Pollard T. D., Mooseker M. S. Direct measurement of actin polymerization rate constants by electron microscopy of actin filaments nucleated by isolated microvillus cores. J Cell Biol. 1981 Mar;88(3):654–659. doi: 10.1083/jcb.88.3.654. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Reichstein E., Korn E. D. Acanthamoeba profilin. A protein of low molecular weight from Acanpthamoeba castellanii that inhibits actin nucleation. J Biol Chem. 1979 Jul 10;254(13):6174–6179. [PubMed] [Google Scholar]
  29. Schliwa M. Proteins associated with cytoplasmic actin. Cell. 1981 Sep;25(3):587–590. doi: 10.1016/0092-8674(81)90166-5. [DOI] [PubMed] [Google Scholar]
  30. Schroeder T. E. Microvilli on sea urchin eggs: a second burst of elongation. Dev Biol. 1978 Jun;64(2):342–346. doi: 10.1016/0012-1606(78)90085-4. [DOI] [PubMed] [Google Scholar]
  31. Schroeder T. E. Surface area change at fertilization: resorption of the mosaic membrane. Dev Biol. 1979 Jun;70(2):306–326. doi: 10.1016/0012-1606(79)90030-7. [DOI] [PubMed] [Google Scholar]
  32. Spudich A., Spudich J. A. Actin in triton-treated cortical preparations of unfertilized and fertilized sea urchin eggs. J Cell Biol. 1979 Jul;82(1):212–226. doi: 10.1083/jcb.82.1.212. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Spudich J. A., Amos L. A. Structure of actin filament bundles from microvilli of sea urchin eggs. J Mol Biol. 1979 Apr 5;129(2):319–331. doi: 10.1016/0022-2836(79)90285-7. [DOI] [PubMed] [Google Scholar]
  34. Spudich J. A., Watt S. The regulation of rabbit skeletal muscle contraction. I. Biochemical studies of the interaction of the tropomyosin-troponin complex with actin and the proteolytic fragments of myosin. J Biol Chem. 1971 Aug 10;246(15):4866–4871. [PubMed] [Google Scholar]
  35. Stryer L. Fluorescence energy transfer as a spectroscopic ruler. Annu Rev Biochem. 1978;47:819–846. doi: 10.1146/annurev.bi.47.070178.004131. [DOI] [PubMed] [Google Scholar]
  36. Taylor D. L., Reidler J., Spudich J. A., Stryer L. Detection of actin assembly by fluorescence energy transfer. J Cell Biol. 1981 May;89(2):362–367. doi: 10.1083/jcb.89.2.362. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Vacquier V. D. Dynamic changes of the egg cortex. Dev Biol. 1981 May;84(1):1–26. doi: 10.1016/0012-1606(81)90366-3. [DOI] [PubMed] [Google Scholar]
  38. Wang L. L., Bryan J. Isolation of calcium-dependent platelet proteins that interact with actin. Cell. 1981 Sep;25(3):637–649. doi: 10.1016/0092-8674(81)90171-9. [DOI] [PubMed] [Google Scholar]
  39. Wang Y. L., Taylor D. L. Probing the dynamic equilibrium of actin polymerization by fluorescence energy transfer. Cell. 1981 Dec;27(3 Pt 2):429–436. doi: 10.1016/0092-8674(81)90384-6. [DOI] [PubMed] [Google Scholar]
  40. Wang Y., Bonder E. M., Mooseker M. S., Taylor D. L. Effects of villin on the polymerization and subunit exchange of actin. Cell Motil. 1983;3(2):151–165. doi: 10.1002/cm.970030205. [DOI] [PubMed] [Google Scholar]
  41. Weeds A. Actin-binding proteins--regulators of cell architecture and motility. Nature. 1982 Apr 29;296(5860):811–816. doi: 10.1038/296811a0. [DOI] [PubMed] [Google Scholar]
  42. Wegner A. Treadmilling of actin at physiological salt concentrations. An analysis of the critical concentrations of actin filaments. J Mol Biol. 1982 Nov 15;161(4):607–615. doi: 10.1016/0022-2836(82)90411-9. [DOI] [PubMed] [Google Scholar]
  43. Yamamoto K., Pardee J. D., Reidler J., Stryer L., Spudich J. A. Mechanism of interaction of Dictyostelium severin with actin filaments. J Cell Biol. 1982 Dec;95(3):711–719. doi: 10.1083/jcb.95.3.711. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES