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. 1992 May 15;89(10):4678–4682. doi: 10.1073/pnas.89.10.4678

Thymosin beta 4 (Fx peptide) is a potent regulator of actin polymerization in living cells.

M C Sanders 1, A L Goldstein 1, Y L Wang 1
PMCID: PMC49146  PMID: 1584803

Abstract

Thymosin beta 4 (beta 4) is a 5-kDa polypeptide originally identified in calf thymus. Although numerous activities have been attributed to beta 4, its physiological role remains elusive. Recently, beta 4 was found to bind actin in human platelet extracts and to inhibit actin polymerization in vitro, raising the possibility that it may be a physiological regulator of actin assembly. To examine this potential function, we have increased the cellular beta 4 concentration by microinjecting synthetic beta 4 into living epithelial cells and fibroblasts. The injection induced a diminution of stress fibers and a dose-dependent depolymerization of actin filaments as indicated by quantitative image analysis of phalloidin binding. Our results show that beta 4 is a potent regulator of actin assembly in living cells.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Amato P. A., Unanue E. R., Taylor D. L. Distribution of actin in spreading macrophages: a comparative study on living and fixed cells. J Cell Biol. 1983 Mar;96(3):750–761. doi: 10.1083/jcb.96.3.750. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bamburg J. R., Bray D. Distribution and cellular localization of actin depolymerizing factor. J Cell Biol. 1987 Dec;105(6 Pt 1):2817–2825. doi: 10.1083/jcb.105.6.2817. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cooper J. A., Blum J. D., Williams R. C., Jr, Pollard T. D. Purification and characterization of actophorin, a new 15,000-dalton actin-binding protein from Acanthamoeba castellanii. J Biol Chem. 1986 Jan 5;261(1):477–485. [PubMed] [Google Scholar]
  4. Cooper J. A. The role of actin polymerization in cell motility. Annu Rev Physiol. 1991;53:585–605. doi: 10.1146/annurev.ph.53.030191.003101. [DOI] [PubMed] [Google Scholar]
  5. Cooper J. A., Walker S. B., Pollard T. D. Pyrene actin: documentation of the validity of a sensitive assay for actin polymerization. J Muscle Res Cell Motil. 1983 Apr;4(2):253–262. doi: 10.1007/BF00712034. [DOI] [PubMed] [Google Scholar]
  6. Erickson-Viitanen S., Ruggieri S., Natalini P., Horecker B. L. Distribution of thymosin beta 4 in vertebrate classes. Arch Biochem Biophys. 1983 Mar;221(2):570–576. doi: 10.1016/0003-9861(83)90177-7. [DOI] [PubMed] [Google Scholar]
  7. Fishkind D. J., Cao L. G., Wang Y. L. Microinjection of the catalytic fragment of myosin light chain kinase into dividing cells: effects on mitosis and cytokinesis. J Cell Biol. 1991 Sep;114(5):967–975. doi: 10.1083/jcb.114.5.967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Glacy S. D. Subcellular distribution of rhodamine-actin microinjected into living fibroblastic cells. J Cell Biol. 1983 Oct;97(4):1207–1213. doi: 10.1083/jcb.97.4.1207. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Goodall G. J., Morgan J. I., Horecker B. L. Thymosin beta 4 in cultured mammalian cell lines. Arch Biochem Biophys. 1983 Mar;221(2):598–601. doi: 10.1016/0003-9861(83)90182-0. [DOI] [PubMed] [Google Scholar]
  10. Graessmann A., Graessmann M., Mueller C. Microinjection of early SV40 DNA fragments and T antigen. Methods Enzymol. 1980;65(1):816–825. doi: 10.1016/s0076-6879(80)65076-9. [DOI] [PubMed] [Google Scholar]
  11. Hannappel E., Leibold W. Biosynthesis rates and content of thymosin beta 4 in cell lines. Arch Biochem Biophys. 1985 Jul;240(1):236–241. doi: 10.1016/0003-9861(85)90028-1. [DOI] [PubMed] [Google Scholar]
  12. Hannappel E. One-step procedure for the determination of thymosin beta 4 in small tissue samples and its separation from other thymosin beta 4-like peptides by high-pressure liquid chromatography. Anal Biochem. 1986 Aug 1;156(2):390–396. doi: 10.1016/0003-2697(86)90270-8. [DOI] [PubMed] [Google Scholar]
  13. Hannappel E., Xu G. J., Morgan J., Hempstead J., Horecker B. L. Thymosin beta 4: a ubiquitous peptide in rat and mouse tissues. Proc Natl Acad Sci U S A. 1982 Apr;79(7):2172–2175. doi: 10.1073/pnas.79.7.2172. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Haritos A. A., Blacher R., Stein S., Caldarella J., Horecker B. L. Primary structure of rat thymus prothymosin alpha. Proc Natl Acad Sci U S A. 1985 Jan;82(2):343–346. doi: 10.1073/pnas.82.2.343. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Holmes K. C., Popp D., Gebhard W., Kabsch W. Atomic model of the actin filament. Nature. 1990 Sep 6;347(6288):44–49. doi: 10.1038/347044a0. [DOI] [PubMed] [Google Scholar]
  16. Hu S. K., Low T. L., Goldstein A. L. Modulation of terminal deoxynucleotidyl transferase activity by thymosin. Mol Cell Biochem. 1981 Dec 4;41:49–58. doi: 10.1007/BF00225296. [DOI] [PubMed] [Google Scholar]
  17. Kouyama T., Mihashi K. Fluorimetry study of N-(1-pyrenyl)iodoacetamide-labelled F-actin. Local structural change of actin protomer both on polymerization and on binding of heavy meromyosin. Eur J Biochem. 1981;114(1):33–38. [PubMed] [Google Scholar]
  18. Kreis T. E., Geiger B., Schlessinger J. Mobility of microinjected rhodamine actin within living chicken gizzard cells determined by fluorescence photobleaching recovery. Cell. 1982 Jul;29(3):835–845. doi: 10.1016/0092-8674(82)90445-7. [DOI] [PubMed] [Google Scholar]
  19. Lambooy P. K., Korn E. D. Purification and characterization of actobindin, a new actin monomer-binding protein from Acanthamoeba castellanii. J Biol Chem. 1986 Dec 25;261(36):17150–17155. [PubMed] [Google Scholar]
  20. Lee G. M. Measurement of volume injected into individual cells by quantitative fluorescence microscopy. J Cell Sci. 1989 Nov;94(Pt 3):443–447. doi: 10.1242/jcs.94.3.443. [DOI] [PubMed] [Google Scholar]
  21. Lind S. E., Janmey P. A., Chaponnier C., Herbert T. J., Stossel T. P. Reversible binding of actin to gelsolin and profilin in human platelet extracts. J Cell Biol. 1987 Aug;105(2):833–842. doi: 10.1083/jcb.105.2.833. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Low T. L., Goldstein A. L. Chemical characterization of thymosin beta 4. J Biol Chem. 1982 Jan 25;257(2):1000–1006. [PubMed] [Google Scholar]
  23. Low T. L., Hu S. K., Goldstein A. L. Complete amino acid sequence of bovine thymosin beta 4: a thymic hormone that induces terminal deoxynucleotidyl transferase activity in thymocyte populations. Proc Natl Acad Sci U S A. 1981 Feb;78(2):1162–1166. doi: 10.1073/pnas.78.2.1162. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Low T. L., Thurman G. B., McAdoo M., McClure J., Rossio J. L., Naylor P. H., Goldstein A. L. The chemistry and biology of thymosin. I. Isolation, characterization, and biological activities of thymosin alpha1 and polypeptide beta1 from calf thymus. J Biol Chem. 1979 Feb 10;254(3):981–986. [PubMed] [Google Scholar]
  25. Low T. L., Wang S. S., Goldstein A. L. Solid-phase synthesis of thymosin beta 4: chemical and biological characterization of the synthetic peptide. Biochemistry. 1983 Feb 15;22(4):733–740. doi: 10.1021/bi00273a004. [DOI] [PubMed] [Google Scholar]
  26. Mckenna N. M., Wang Y. L. Culturing cells on the microscope stage. Methods Cell Biol. 1989;29:195–205. doi: 10.1016/s0091-679x(08)60195-8. [DOI] [PubMed] [Google Scholar]
  27. Nishida E., Maekawa S., Sakai H. Cofilin, a protein in porcine brain that binds to actin filaments and inhibits their interactions with myosin and tropomyosin. Biochemistry. 1984 Oct 23;23(22):5307–5313. doi: 10.1021/bi00317a032. [DOI] [PubMed] [Google Scholar]
  28. Pinder J. C., Gratzer W. B. Investigation of the actin-deoxyribonuclease I interaction using a pyrene-conjugated actin derivative. Biochemistry. 1982 Sep 28;21(20):4886–4890. doi: 10.1021/bi00263a009. [DOI] [PubMed] [Google Scholar]
  29. Podolski J. L., Steck T. L. Association of deoxyribonuclease I with the pointed ends of actin filaments in human red blood cell membrane skeletons. J Biol Chem. 1988 Jan 15;263(2):638–645. [PubMed] [Google Scholar]
  30. Pollard T. D., Cooper J. A. Actin and actin-binding proteins. A critical evaluation of mechanisms and functions. Annu Rev Biochem. 1986;55:987–1035. doi: 10.1146/annurev.bi.55.070186.005011. [DOI] [PubMed] [Google Scholar]
  31. Safer D., Elzinga M., Nachmias V. T. Thymosin beta 4 and Fx, an actin-sequestering peptide, are indistinguishable. J Biol Chem. 1991 Mar 5;266(7):4029–4032. [PubMed] [Google Scholar]
  32. Safer D., Golla R., Nachmias V. T. Isolation of a 5-kilodalton actin-sequestering peptide from human blood platelets. Proc Natl Acad Sci U S A. 1990 Apr;87(7):2536–2540. doi: 10.1073/pnas.87.7.2536. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Sanders M. C., Wang Y. L. Exogenous nucleation sites fail to induce detectable polymerization of actin in living cells. J Cell Biol. 1990 Feb;110(2):359–365. doi: 10.1083/jcb.110.2.359. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Sanger J. M., Dabiri G., Mittal B., Kowalski M. A., Haddad J. G., Sanger J. W. Disruption of microfilament organization in living nonmuscle cells by microinjection of plasma vitamin D-binding protein or DNase I. Proc Natl Acad Sci U S A. 1990 Jul;87(14):5474–5478. doi: 10.1073/pnas.87.14.5474. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Small J. V., Rinnerthaler G., Hinssen H. Organization of actin meshworks in cultured cells: the leading edge. Cold Spring Harb Symp Quant Biol. 1982;46(Pt 2):599–611. doi: 10.1101/sqb.1982.046.01.056. [DOI] [PubMed] [Google Scholar]
  36. Stossel T. P., Chaponnier C., Ezzell R. M., Hartwig J. H., Janmey P. A., Kwiatkowski D. J., Lind S. E., Smith D. B., Southwick F. S., Yin H. L. Nonmuscle actin-binding proteins. Annu Rev Cell Biol. 1985;1:353–402. doi: 10.1146/annurev.cb.01.110185.002033. [DOI] [PubMed] [Google Scholar]
  37. Stossel T. P. From signal to pseudopod. How cells control cytoplasmic actin assembly. J Biol Chem. 1989 Nov 5;264(31):18261–18264. [PubMed] [Google Scholar]
  38. Takagi T., Konishi K., Mabuchi I. Amino acid sequence of starfish oocyte depactin. J Biol Chem. 1988 Mar 5;263(7):3097–3102. [PubMed] [Google Scholar]
  39. Vancompernolle K., Vandekerckhove J., Bubb M. R., Korn E. D. The interfaces of actin and Acanthamoeba actobindin. Identification of a new actin-binding motif. J Biol Chem. 1991 Aug 15;266(23):15427–15431. [PubMed] [Google Scholar]
  40. Wang S. S., Wang B. S., Chang J. K., Low T. L., Goldstein A. L. Synthesis of thymosin beta 4. Int J Pept Protein Res. 1981 Oct;18(4):413–415. [PubMed] [Google Scholar]
  41. Weeds A., Way M. Is thymosin-beta4 the missing link? Curr Biol. 1991 Oct;1(5):307–308. doi: 10.1016/0960-9822(91)90093-c. [DOI] [PubMed] [Google Scholar]
  42. Yonezawa N., Nishida E., Ohba M., Seki M., Kumagai H., Sakai H. An actin-interacting heptapeptide in the cofilin sequence. Eur J Biochem. 1989 Jul 15;183(1):235–238. doi: 10.1111/j.1432-1033.1989.tb14918.x. [DOI] [PubMed] [Google Scholar]

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