Skip to main content
PMC home page
Molecular and Cellular Biology logoLink to Molecular and Cellular Biology
. 1994 Dec;14(12):8292–8303. doi: 10.1128/mcb.14.12.8292

The Ikaros gene encodes a family of functionally diverse zinc finger DNA-binding proteins.

A Molnár 1, K Georgopoulos 1
PMCID: PMC359368  PMID: 7969165

Abstract

We previously described the lymphocyte-restricted Ikaros gene encoding a zinc finger DNA-binding protein as a potential regulator of lymphocyte commitment and differentiation. Here, we report the isolation of four additional Ikaros transcripts, products of alternate splicing that encode functionally diverse proteins. The Ikaros proteins contain unique combinations of zinc finger modules that dictate their overall sequence specificity and affinity. The Ik-1 and Ik-2 proteins can both bind, albeit with different affinities, to the same recognition sequences present in a number of lymphocyte-specific regulatory elements. The Ik-3 and the Ik-4 proteins interact only with a subset of these motifs. The Ik-1 and Ik-2 proteins can strongly stimulate transcription, whereas Ik-3 and Ik-4 are weak activators. Significantly, the transcription activation potential of the Ikaros proteins correlates with their subcellular localization. Upon ectopic expression of the Ikaros isoforms in nonlymphoid cells, Ik-1 and Ik-2 localize to the nucleus, whereas Ik-3 and Ik-4 are predominantly found in the cytoplasm. The Ikaros isoforms are expressed differentially in lymphocytes: Ik-1 and Ik-2 mRNAs are the predominating forms, and Ik-4 is present in significant amounts only in early T-cell progenitors, whereas Ik-3 and Ik-5 transcripts are expressed at relatively low levels throughout lymphocyte development. The ability of the Ikaros gene to generate functionally diverse proteins that may participate in distinct regulatory pathways substantiates its role as a master regulator during lymphocyte development.

Full text

PDF
8292

Images in this article

8295Image
on p.8295
8297Image
on p.8297
8298Image
on p.8298
8300Image
on p.8300
8301Image
on p.8301

Selected References

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

  1. Adams B., Dörfler P., Aguzzi A., Kozmik Z., Urbánek P., Maurer-Fogy I., Busslinger M. Pax-5 encodes the transcription factor BSAP and is expressed in B lymphocytes, the developing CNS, and adult testis. Genes Dev. 1992 Sep;6(9):1589–1607. doi: 10.1101/gad.6.9.1589. [DOI] [PubMed] [Google Scholar]
  2. Ansorge W., Pepperkok R. Performance of an automated system for capillary microinjection into living cells. J Biochem Biophys Methods. 1988 Aug;16(4):283–292. doi: 10.1016/0165-022x(88)90062-0. [DOI] [PubMed] [Google Scholar]
  3. Baldwin A. S., Jr, Sharp P. A. Binding of a nuclear factor to a regulatory sequence in the promoter of the mouse H-2Kb class I major histocompatibility gene. Mol Cell Biol. 1987 Jan;7(1):305–313. doi: 10.1128/mcb.7.1.305. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Ballard D. W., Walker W. H., Doerre S., Sista P., Molitor J. A., Dixon E. P., Peffer N. J., Hannink M., Greene W. C. The v-rel oncogene encodes a kappa B enhancer binding protein that inhibits NF-kappa B function. Cell. 1990 Nov 16;63(4):803–814. doi: 10.1016/0092-8674(90)90146-6. [DOI] [PubMed] [Google Scholar]
  5. Blackwood E. M., Eisenman R. N. Max: a helix-loop-helix zipper protein that forms a sequence-specific DNA-binding complex with Myc. Science. 1991 Mar 8;251(4998):1211–1217. doi: 10.1126/science.2006410. [DOI] [PubMed] [Google Scholar]
  6. Bours V., Franzoso G., Azarenko V., Park S., Kanno T., Brown K., Siebenlist U. The oncoprotein Bcl-3 directly transactivates through kappa B motifs via association with DNA-binding p50B homodimers. Cell. 1993 Mar 12;72(5):729–739. doi: 10.1016/0092-8674(93)90401-b. [DOI] [PubMed] [Google Scholar]
  7. Böhnlein E., Lowenthal J. W., Siekevitz M., Ballard D. W., Franza B. R., Greene W. C. The same inducible nuclear proteins regulates mitogen activation of both the interleukin-2 receptor-alpha gene and type 1 HIV. Cell. 1988 Jun 3;53(5):827–836. doi: 10.1016/0092-8674(88)90099-2. [DOI] [PubMed] [Google Scholar]
  8. Clevers H. C., Oosterwegel M. A., Georgopoulos K. Transcription factors in early T-cell development. Immunol Today. 1993 Dec;14(12):591–596. doi: 10.1016/0167-5699(93)90198-T. [DOI] [PubMed] [Google Scholar]
  9. Clevers H., Lonberg N., Dunlap S., Lacy E., Terhorst C. An enhancer located in a CpG-island 3' to the TCR/CD3-epsilon gene confers T lymphocyte-specificity to its promoter. EMBO J. 1989 Sep;8(9):2527–2535. doi: 10.1002/j.1460-2075.1989.tb08390.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Delwel R., Funabiki T., Kreider B. L., Morishita K., Ihle J. N. Four of the seven zinc fingers of the Evi-1 myeloid-transforming gene are required for sequence-specific binding to GA(C/T)AAGA(T/C)AAGATAA. Mol Cell Biol. 1993 Jul;13(7):4291–4300. doi: 10.1128/mcb.13.7.4291. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Durand D. B., Shaw J. P., Bush M. R., Replogle R. E., Belagaje R., Crabtree G. R. Characterization of antigen receptor response elements within the interleukin-2 enhancer. Mol Cell Biol. 1988 Apr;8(4):1715–1724. doi: 10.1128/mcb.8.4.1715. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Franzoso G., Bours V., Azarenko V., Park S., Tomita-Yamaguchi M., Kanno T., Brown K., Siebenlist U. The oncoprotein Bcl-3 can facilitate NF-kappa B-mediated transactivation by removing inhibiting p50 homodimers from select kappa B sites. EMBO J. 1993 Oct;12(10):3893–3901. doi: 10.1002/j.1460-2075.1993.tb06067.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gashler A. L., Swaminathan S., Sukhatme V. P. A novel repression module, an extensive activation domain, and a bipartite nuclear localization signal defined in the immediate-early transcription factor Egr-1. Mol Cell Biol. 1993 Aug;13(8):4556–4571. doi: 10.1128/mcb.13.8.4556. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Georgopoulos K., Bigby M., Wang J. H., Molnar A., Wu P., Winandy S., Sharpe A. The Ikaros gene is required for the development of all lymphoid lineages. Cell. 1994 Oct 7;79(1):143–156. doi: 10.1016/0092-8674(94)90407-3. [DOI] [PubMed] [Google Scholar]
  15. Georgopoulos K., Galson D., Terhorst C. Tissue-specific nuclear factors mediate expression of the CD3 delta gene during T cell development. EMBO J. 1990 Jan;9(1):109–115. doi: 10.1002/j.1460-2075.1990.tb08086.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Georgopoulos K., Moore D. D., Derfler B. Ikaros, an early lymphoid-specific transcription factor and a putative mediator for T cell commitment. Science. 1992 Oct 30;258(5083):808–812. doi: 10.1126/science.1439790. [DOI] [PubMed] [Google Scholar]
  17. Georgopoulos K., van den Elsen P., Bier E., Maxam A., Terhorst C. A T cell-specific enhancer is located in a DNase I-hypersensitive area at the 3' end of the CD3-delta gene. EMBO J. 1988 Aug;7(8):2401–2407. doi: 10.1002/j.1460-2075.1988.tb03085.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Gogos J. A., Hsu T., Bolton J., Kafatos F. C. Sequence discrimination by alternatively spliced isoforms of a DNA binding zinc finger domain. Science. 1992 Sep 25;257(5078):1951–1955. doi: 10.1126/science.1290524. [DOI] [PubMed] [Google Scholar]
  19. Gottschalk L. R., Leiden J. M. Identification and functional characterization of the human T-cell receptor beta gene transcriptional enhancer: common nuclear proteins interact with the transcriptional regulatory elements of the T-cell receptor alpha and beta genes. Mol Cell Biol. 1990 Oct;10(10):5486–5495. doi: 10.1128/mcb.10.10.5486. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Hagman J., Belanger C., Travis A., Turck C. W., Grosschedl R. Cloning and functional characterization of early B-cell factor, a regulator of lymphocyte-specific gene expression. Genes Dev. 1993 May;7(5):760–773. doi: 10.1101/gad.7.5.760. [DOI] [PubMed] [Google Scholar]
  21. Hagman J., Travis A., Grosschedl R. A novel lineage-specific nuclear factor regulates mb-1 gene transcription at the early stages of B cell differentiation. EMBO J. 1991 Nov;10(11):3409–3417. doi: 10.1002/j.1460-2075.1991.tb04905.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Ho I. C., Bhat N. K., Gottschalk L. R., Lindsten T., Thompson C. B., Papas T. S., Leiden J. M. Sequence-specific binding of human Ets-1 to the T cell receptor alpha gene enhancer. Science. 1990 Nov 9;250(4982):814–818. doi: 10.1126/science.2237431. [DOI] [PubMed] [Google Scholar]
  23. Ho I. C., Leiden J. M. Regulation of the human T-cell receptor alpha gene enhancer: multiple ubiquitous and T-cell-specific nuclear proteins interact with four hypomethylated enhancer elements. Mol Cell Biol. 1990 Sep;10(9):4720–4727. doi: 10.1128/mcb.10.9.4720. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Ho I. C., Vorhees P., Marin N., Oakley B. K., Tsai S. F., Orkin S. H., Leiden J. M. Human GATA-3: a lineage-restricted transcription factor that regulates the expression of the T cell receptor alpha gene. EMBO J. 1991 May;10(5):1187–1192. doi: 10.1002/j.1460-2075.1991.tb08059.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Hsu T., Gogos J. A., Kirsh S. A., Kafatos F. C. Multiple zinc finger forms resulting from developmentally regulated alternative splicing of a transcription factor gene. Science. 1992 Sep 25;257(5078):1946–1950. doi: 10.1126/science.1411512. [DOI] [PubMed] [Google Scholar]
  26. Kreider B. L., Orkin S. H., Ihle J. N. Loss of erythropoietin responsiveness in erythroid progenitors due to expression of the Evi-1 myeloid-transforming gene. Proc Natl Acad Sci U S A. 1993 Jul 15;90(14):6454–6458. doi: 10.1073/pnas.90.14.6454. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Kuang A. A., Novak K. D., Kang S. M., Bruhn K., Lenardo M. J. Interaction between NF-kappa B- and serum response factor-binding elements activates an interleukin-2 receptor alpha-chain enhancer specifically in T lymphocytes. Mol Cell Biol. 1993 Apr;13(4):2536–2545. doi: 10.1128/mcb.13.4.2536. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Kunsch C., Ruben S. M., Rosen C. A. Selection of optimal kappa B/Rel DNA-binding motifs: interaction of both subunits of NF-kappa B with DNA is required for transcriptional activation. Mol Cell Biol. 1992 Oct;12(10):4412–4421. doi: 10.1128/mcb.12.10.4412. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Lenardo M. J., Baltimore D. NF-kappa B: a pleiotropic mediator of inducible and tissue-specific gene control. Cell. 1989 Jul 28;58(2):227–229. doi: 10.1016/0092-8674(89)90833-7. [DOI] [PubMed] [Google Scholar]
  30. Lenardo M. J., Fan C. M., Maniatis T., Baltimore D. The involvement of NF-kappa B in beta-interferon gene regulation reveals its role as widely inducible mediator of signal transduction. Cell. 1989 Apr 21;57(2):287–294. doi: 10.1016/0092-8674(89)90966-5. [DOI] [PubMed] [Google Scholar]
  31. Lo K., Landau N. R., Smale S. T. LyF-1, a transcriptional regulator that interacts with a novel class of promoters for lymphocyte-specific genes. Mol Cell Biol. 1991 Oct;11(10):5229–5243. doi: 10.1128/mcb.11.10.5229. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Oosterwegel M., van de Wetering M., Timmerman J., Kruisbeek A., Destree O., Meijlink F., Clevers H. Differential expression of the HMG box factors TCF-1 and LEF-1 during murine embryogenesis. Development. 1993 Jun;118(2):439–448. doi: 10.1242/dev.118.2.439. [DOI] [PubMed] [Google Scholar]
  33. Pagano M., Theodoras A. M., Tam S. W., Draetta G. F. Cyclin D1-mediated inhibition of repair and replicative DNA synthesis in human fibroblasts. Genes Dev. 1994 Jul 15;8(14):1627–1639. doi: 10.1101/gad.8.14.1627. [DOI] [PubMed] [Google Scholar]
  34. Pavletich N. P., Pabo C. O. Crystal structure of a five-finger GLI-DNA complex: new perspectives on zinc fingers. Science. 1993 Sep 24;261(5129):1701–1707. doi: 10.1126/science.8378770. [DOI] [PubMed] [Google Scholar]
  35. Pavletich N. P., Pabo C. O. Zinc finger-DNA recognition: crystal structure of a Zif268-DNA complex at 2.1 A. Science. 1991 May 10;252(5007):809–817. doi: 10.1126/science.2028256. [DOI] [PubMed] [Google Scholar]
  36. Pollock R., Treisman R. A sensitive method for the determination of protein-DNA binding specificities. Nucleic Acids Res. 1990 Nov 11;18(21):6197–6204. doi: 10.1093/nar/18.21.6197. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Redondo J. M., Hata S., Brocklehurst C., Krangel M. S. A T cell-specific transcriptional enhancer within the human T cell receptor delta locus. Science. 1990 Mar 9;247(4947):1225–1229. doi: 10.1126/science.2156339. [DOI] [PubMed] [Google Scholar]
  38. Serfling E., Barthelmäs R., Pfeuffer I., Schenk B., Zarius S., Swoboda R., Mercurio F., Karin M. Ubiquitous and lymphocyte-specific factors are involved in the induction of the mouse interleukin 2 gene in T lymphocytes. EMBO J. 1989 Feb;8(2):465–473. doi: 10.1002/j.1460-2075.1989.tb03399.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Smith D. B., Johnson K. S. Single-step purification of polypeptides expressed in Escherichia coli as fusions with glutathione S-transferase. Gene. 1988 Jul 15;67(1):31–40. doi: 10.1016/0378-1119(88)90005-4. [DOI] [PubMed] [Google Scholar]
  40. Sun S. C., Ganchi P. A., Ballard D. W., Greene W. C. NF-kappa B controls expression of inhibitor I kappa B alpha: evidence for an inducible autoregulatory pathway. Science. 1993 Mar 26;259(5103):1912–1915. doi: 10.1126/science.8096091. [DOI] [PubMed] [Google Scholar]
  41. Thompson C. B., Wang C. Y., Ho I. C., Bohjanen P. R., Petryniak B., June C. H., Miesfeldt S., Zhang L., Nabel G. J., Karpinski B. cis-acting sequences required for inducible interleukin-2 enhancer function bind a novel Ets-related protein, Elf-1. Mol Cell Biol. 1992 Mar;12(3):1043–1053. doi: 10.1128/mcb.12.3.1043. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Travis A., Amsterdam A., Belanger C., Grosschedl R. LEF-1, a gene encoding a lymphoid-specific protein with an HMG domain, regulates T-cell receptor alpha enhancer function [corrected]. Genes Dev. 1991 May;5(5):880–894. doi: 10.1101/gad.5.5.880. [DOI] [PubMed] [Google Scholar]
  43. Waterman M. L., Fischer W. H., Jones K. A. A thymus-specific member of the HMG protein family regulates the human T cell receptor C alpha enhancer. Genes Dev. 1991 Apr;5(4):656–669. doi: 10.1101/gad.5.4.656. [DOI] [PubMed] [Google Scholar]
  44. Xu Y., Baldassare M., Fisher P., Rathbun G., Oltz E. M., Yancopoulos G. D., Jessell T. M., Alt F. W. LH-2: a LIM/homeodomain gene expressed in developing lymphocytes and neural cells. Proc Natl Acad Sci U S A. 1993 Jan 1;90(1):227–231. doi: 10.1073/pnas.90.1.227. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. van de Wetering M., Oosterwegel M., Dooijes D., Clevers H. Identification and cloning of TCF-1, a T lymphocyte-specific transcription factor containing a sequence-specific HMG box. EMBO J. 1991 Jan;10(1):123–132. doi: 10.1002/j.1460-2075.1991.tb07928.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Molecular and Cellular Biology are provided here courtesy of Taylor & Francis

RESOURCES