Synergistic activation of the fibroblast growth factor 4 enhancer by Sox2 and Oct-3 depends on protein-protein interactions facilitated by a specific spatial arrangement of factor binding sites (original) (raw)

Abstract

Octamer binding and Sox factors are thought to play important roles in development by potentiating the transcriptional activation of specific gene subsets. The proteins within these factor families are related by the presence of highly conserved DNA binding domains, the octamer binding protein POU domain or the Sox factors HMG domain. We have previously shown that fibroblast growth factor 4 (FGF-4) gene expression in embryonal carcinoma cells requires a synergistic interaction between Oct-3 and Sox2 on the FGF-4 enhancer. Sox2 and Oct-3 bind to adjacent sites within this enhancer to form a ternary protein-DNA complex (Oct-3*) whose assembly correlates with enhancer activity. We now demonstrate that increasing the distance between the octamer and Sox binding sites by base pair insertion results in a loss of enhancer function. Significantly, those enhancer "spacing mutants" which failed to activate transcription were also compromised in their ability to form the Oct* complexes even though they could still bind both Sox2 and the octamer binding proteins, suggesting that a direct interaction between Sox2 and Oct-3 is necessary for enhancer function. Consistent with this hypothesis, Oct-3 and Sox2 can participate in a direct protein-protein interaction in vitro in the absence of DNA, and both this interaction and assembly of the ternary Oct* complexes require only the octamer protein POU and Sox2 HMG domains. Assembly of the ternary complex by these two protein domains occurs in a cooperative manner on FGF-4 enhancer DNA, and the loss of this cooperative interaction contributes to the defect in Oct-3* formation observed for the enhancer spacing mutants. These observations indicate that Oct-3* assembly results from protein-protein interactions between the domains of Sox2 and Oct-3 that mediate their binding to DNA, but it also requires a specific arrangement of the binding sites within the FGF-4 enhancer DNA. Thus, these results define one parameter that is fundamental to synergistic activation by Sox2 and Oct-3 and further emphasize the critical role of enhancer DNA sequences in the proper assembly of functional activation complexes.

Full Text

The Full Text of this article is available as a PDF (786.9 KB).

Selected References

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

  1. Aurora R., Herr W. Segments of the POU domain influence one another's DNA-binding specificity. Mol Cell Biol. 1992 Feb;12(2):455–467. doi: 10.1128/mcb.12.2.455. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Brehm A., Ohbo K., Schöler H. The carboxy-terminal transactivation domain of Oct-4 acquires cell specificity through the POU domain. Mol Cell Biol. 1997 Jan;17(1):154–162. doi: 10.1128/mcb.17.1.154. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Carlsson P., Waterman M. L., Jones K. A. The hLEF/TCF-1 alpha HMG protein contains a context-dependent transcriptional activation domain that induces the TCR alpha enhancer in T cells. Genes Dev. 1993 Dec;7(12A):2418–2430. doi: 10.1101/gad.7.12a.2418. [DOI] [PubMed] [Google Scholar]
  4. Curatola A. M., Basilico C. Expression of the K-fgf proto-oncogene is controlled by 3' regulatory elements which are specific for embryonal carcinoma cells. Mol Cell Biol. 1990 Jun;10(6):2475–2484. doi: 10.1128/mcb.10.6.2475. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Dailey L., Yuan H., Basilico C. Interaction between a novel F9-specific factor and octamer-binding proteins is required for cell-type-restricted activity of the fibroblast growth factor 4 enhancer. Mol Cell Biol. 1994 Dec;14(12):7758–7769. doi: 10.1128/mcb.14.12.7758. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Delli Bovi P., Curatola A. M., Kern F. G., Greco A., Ittmann M., Basilico C. An oncogene isolated by transfection of Kaposi's sarcoma DNA encodes a growth factor that is a member of the FGF family. Cell. 1987 Aug 28;50(5):729–737. doi: 10.1016/0092-8674(87)90331-x. [DOI] [PubMed] [Google Scholar]
  7. Denny P., Swift S., Connor F., Ashworth A. An SRY-related gene expressed during spermatogenesis in the mouse encodes a sequence-specific DNA-binding protein. EMBO J. 1992 Oct;11(10):3705–3712. doi: 10.1002/j.1460-2075.1992.tb05455.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Feldman B., Poueymirou W., Papaioannou V. E., DeChiara T. M., Goldfarb M. Requirement of FGF-4 for postimplantation mouse development. Science. 1995 Jan 13;267(5195):246–249. doi: 10.1126/science.7809630. [DOI] [PubMed] [Google Scholar]
  9. Giese K., Grosschedl R. LEF-1 contains an activation domain that stimulates transcription only in a specific context of factor-binding sites. EMBO J. 1993 Dec;12(12):4667–4676. doi: 10.1002/j.1460-2075.1993.tb06155.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Gstaiger M., Georgiev O., van Leeuwen H., van der Vliet P., Schaffner W. The B cell coactivator Bob1 shows DNA sequence-dependent complex formation with Oct-1/Oct-2 factors, leading to differential promoter activation. EMBO J. 1996 Jun 3;15(11):2781–2790. [PMC free article] [PubMed] [Google Scholar]
  11. Gstaiger M., Knoepfel L., Georgiev O., Schaffner W., Hovens C. M. A B-cell coactivator of octamer-binding transcription factors. Nature. 1995 Jan 26;373(6512):360–362. doi: 10.1038/373360a0. [DOI] [PubMed] [Google Scholar]
  12. Gubbay J., Collignon J., Koopman P., Capel B., Economou A., Münsterberg A., Vivian N., Goodfellow P., Lovell-Badge R. A gene mapping to the sex-determining region of the mouse Y chromosome is a member of a novel family of embryonically expressed genes. Nature. 1990 Jul 19;346(6281):245–250. doi: 10.1038/346245a0. [DOI] [PubMed] [Google Scholar]
  13. Herskowitz I. A regulatory hierarchy for cell specialization in yeast. Nature. 1989 Dec 14;342(6251):749–757. doi: 10.1038/342749a0. [DOI] [PubMed] [Google Scholar]
  14. Huang C. C., Herr W. Differential control of transcription by homologous homeodomain coregulators. Mol Cell Biol. 1996 Jun;16(6):2967–2976. doi: 10.1128/mcb.16.6.2967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Imagawa M., Miyamoto A., Shirakawa M., Hamada H., Muramatsu M. Stringent integrity requirements for both trans-activation and DNA-binding in a trans-activator, Oct3. Nucleic Acids Res. 1991 Aug 25;19(16):4503–4508. doi: 10.1093/nar/19.16.4503. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Jin Y., Mead J., Li T., Wolberger C., Vershon A. K. Altered DNA recognition and bending by insertions in the alpha 2 tail of the yeast a1/alpha 2 homeodomain heterodimer. Science. 1995 Oct 13;270(5234):290–293. doi: 10.1126/science.270.5234.290. [DOI] [PubMed] [Google Scholar]
  17. Kamachi Y., Sockanathan S., Liu Q., Breitman M., Lovell-Badge R., Kondoh H. Involvement of SOX proteins in lens-specific activation of crystallin genes. EMBO J. 1995 Jul 17;14(14):3510–3519. doi: 10.1002/j.1460-2075.1995.tb07357.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Lai J. S., Cleary M. A., Herr W. A single amino acid exchange transfers VP16-induced positive control from the Oct-1 to the Oct-2 homeo domain. Genes Dev. 1992 Nov;6(11):2058–2065. doi: 10.1101/gad.6.11.2058. [DOI] [PubMed] [Google Scholar]
  19. Lai J. S., Herr W. Ethidium bromide provides a simple tool for identifying genuine DNA-independent protein associations. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):6958–6962. doi: 10.1073/pnas.89.15.6958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Lefstin J. A., Thomas J. R., Yamamoto K. R. Influence of a steroid receptor DNA-binding domain on transcriptional regulatory functions. Genes Dev. 1994 Dec 1;8(23):2842–2856. doi: 10.1101/gad.8.23.2842. [DOI] [PubMed] [Google Scholar]
  21. Leger H., Sock E., Renner K., Grummt F., Wegner M. Functional interaction between the POU domain protein Tst-1/Oct-6 and the high-mobility-group protein HMG-I/Y. Mol Cell Biol. 1995 Jul;15(7):3738–3747. doi: 10.1128/mcb.15.7.3738. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Luo Y., Roeder R. G. Cloning, functional characterization, and mechanism of action of the B-cell-specific transcriptional coactivator OCA-B. Mol Cell Biol. 1995 Aug;15(8):4115–4124. doi: 10.1128/mcb.15.8.4115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Mann R. S., Chan S. K. Extra specificity from extradenticle: the partnership between HOX and PBX/EXD homeodomain proteins. Trends Genet. 1996 Jul;12(7):258–262. doi: 10.1016/0168-9525(96)10026-3. [DOI] [PubMed] [Google Scholar]
  24. Niswander L., Martin G. R. Fgf-4 expression during gastrulation, myogenesis, limb and tooth development in the mouse. Development. 1992 Mar;114(3):755–768. doi: 10.1242/dev.114.3.755. [DOI] [PubMed] [Google Scholar]
  25. Niswander L., Tickle C., Vogel A., Booth I., Martin G. R. FGF-4 replaces the apical ectodermal ridge and directs outgrowth and patterning of the limb. Cell. 1993 Nov 5;75(3):579–587. doi: 10.1016/0092-8674(93)90391-3. [DOI] [PubMed] [Google Scholar]
  26. Okamoto K., Okazawa H., Okuda A., Sakai M., Muramatsu M., Hamada H. A novel octamer binding transcription factor is differentially expressed in mouse embryonic cells. Cell. 1990 Feb 9;60(3):461–472. doi: 10.1016/0092-8674(90)90597-8. [DOI] [PubMed] [Google Scholar]
  27. Perkins N. D., Edwards N. L., Duckett C. S., Agranoff A. B., Schmid R. M., Nabel G. J. A cooperative interaction between NF-kappa B and Sp1 is required for HIV-1 enhancer activation. EMBO J. 1993 Sep;12(9):3551–3558. doi: 10.1002/j.1460-2075.1993.tb06029.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Perlmann T., Rangarajan P. N., Umesono K., Evans R. M. Determinants for selective RAR and TR recognition of direct repeat HREs. Genes Dev. 1993 Jul;7(7B):1411–1422. doi: 10.1101/gad.7.7b.1411. [DOI] [PubMed] [Google Scholar]
  29. Pomerantz J. L., Kristie T. M., Sharp P. A. Recognition of the surface of a homeo domain protein. Genes Dev. 1992 Nov;6(11):2047–2057. doi: 10.1101/gad.6.11.2047. [DOI] [PubMed] [Google Scholar]
  30. Schöler H. R. Octamania: the POU factors in murine development. Trends Genet. 1991 Oct;7(10):323–329. doi: 10.1016/0168-9525(91)90422-m. [DOI] [PubMed] [Google Scholar]
  31. Sinclair A. H., Berta P., Palmer M. S., Hawkins J. R., Griffiths B. L., Smith M. J., Foster J. W., Frischauf A. M., Lovell-Badge R., Goodfellow P. N. A gene from the human sex-determining region encodes a protein with homology to a conserved DNA-binding motif. Nature. 1990 Jul 19;346(6281):240–244. doi: 10.1038/346240a0. [DOI] [PubMed] [Google Scholar]
  32. Stern S., Tanaka M., Herr W. The Oct-1 homoeodomain directs formation of a multiprotein-DNA complex with the HSV transactivator VP16. Nature. 1989 Oct 19;341(6243):624–630. doi: 10.1038/341624a0. [DOI] [PubMed] [Google Scholar]
  33. Strubin M., Newell J. W., Matthias P. OBF-1, a novel B cell-specific coactivator that stimulates immunoglobulin promoter activity through association with octamer-binding proteins. Cell. 1995 Feb 10;80(3):497–506. doi: 10.1016/0092-8674(95)90500-6. [DOI] [PubMed] [Google Scholar]
  34. Sturm R. A., Das G., Herr W. The ubiquitous octamer-binding protein Oct-1 contains a POU domain with a homeo box subdomain. Genes Dev. 1988 Dec;2(12A):1582–1599. doi: 10.1101/gad.2.12a.1582. [DOI] [PubMed] [Google Scholar]
  35. Taira M., Yoshida T., Miyagawa K., Sakamoto H., Terada M., Sugimura T. cDNA sequence of human transforming gene hst and identification of the coding sequence required for transforming activity. Proc Natl Acad Sci U S A. 1987 May;84(9):2980–2984. doi: 10.1073/pnas.84.9.2980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Tanaka M., Lai J. S., Herr W. Promoter-selective activation domains in Oct-1 and Oct-2 direct differential activation of an snRNA and mRNA promoter. Cell. 1992 Feb 21;68(4):755–767. doi: 10.1016/0092-8674(92)90150-b. [DOI] [PubMed] [Google Scholar]
  37. 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]
  38. Treisman R., Marais R., Wynne J. Spatial flexibility in ternary complexes between SRF and its accessory proteins. EMBO J. 1992 Dec;11(12):4631–4640. doi: 10.1002/j.1460-2075.1992.tb05565.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Velcich A., Delli-Bovi P., Mansukhani A., Ziff E. B., Basilico C. Expression of the K-fgf protooncogene is repressed during differentiation of F9 cells. Oncogene Res. 1989;5(1):31–37. [PubMed] [Google Scholar]
  40. Verrijzer C. P., van Oosterhout J. A., van der Vliet P. C. The Oct-1 POU domain mediates interactions between Oct-1 and other POU proteins. Mol Cell Biol. 1992 Feb;12(2):542–551. doi: 10.1128/mcb.12.2.542. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Walker S., Hayes S., O'Hare P. Site-specific conformational alteration of the Oct-1 POU domain-DNA complex as the basis for differential recognition by Vmw65 (VP16). Cell. 1994 Dec 2;79(5):841–852. doi: 10.1016/0092-8674(94)90073-6. [DOI] [PubMed] [Google Scholar]
  42. Waterman M. L., Jones K. A. Purification of TCF-1 alpha, a T-cell-specific transcription factor that activates the T-cell receptor C alpha gene enhancer in a context-dependent manner. New Biol. 1990 Jul;2(7):621–636. [PubMed] [Google Scholar]
  43. Yuan H., Corbi N., Basilico C., Dailey L. Developmental-specific activity of the FGF-4 enhancer requires the synergistic action of Sox2 and Oct-3. Genes Dev. 1995 Nov 1;9(21):2635–2645. doi: 10.1101/gad.9.21.2635. [DOI] [PubMed] [Google Scholar]
  44. Zwilling S., König H., Wirth T. High mobility group protein 2 functionally interacts with the POU domains of octamer transcription factors. EMBO J. 1995 Mar 15;14(6):1198–1208. doi: 10.1002/j.1460-2075.1995.tb07103.x. [DOI] [PMC free article] [PubMed] [Google Scholar]