Abstract
The dioxin receptor mediates signal transduction by dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin) and binds to DNA target sequences as a heterodimer of the approximately 100 kDa ligand binding receptor and the approximately 85 kDa auxiliary factor, Arnt. Both of these factors encompass an N-terminal basic helix-loop-helix (bHLH) motif required for DNA binding and dimerization. In this study we describe the construction of glucocorticoid/dioxin receptor fusion proteins which allow the regulation of glucocorticoid receptor activity by dioxin in transient transfections of CHO and hepatoma cells. Thus, in the absence of dioxin, chimeric receptor constructs which contain large 500-720 amino acid C-terminal dioxin receptor fragments, but lack the N-terminal bHLH motif, confer repression upon the transcriptional activity of a glucocorticoid receptor derivative, tau DBD, containing its N-terminal strong transactivating signal (tau) and its DNA binding domain (DBD). In the presence of dioxin, this repression is reversed. Importantly, these chimeric receptors did not require the bHLH Arnt co-factor for function. A considerably smaller region of the dioxin receptor, located between amino acids 230 and 421, showed specific dioxin binding activity in vitro. Moreover, dioxin binding in vitro correlated with the ability of receptor fragments to form stable complexes in vitro with the molecular chaperone hsp90. These findings support the notion that hsp90 may be important for folding of a dioxin binding configuration of the receptor. Finally, tau DBD activity was constitutively repressed in a dioxin non-responsive manner by dioxin receptor fragments which failed to bind ligand but also failed to bind hsp90 in vitro, indicating that alternative mechanisms in addition to hsp90 binding may contribute to the inactivation function. In summary, the dioxin receptor system provides a novel and complex model of regulation of bHLH factors that may also give important insights into the mechanism of action of ligand-activated nuclear receptors.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Alksnis M., Barkhem T., Strömstedt P. E., Ahola H., Kutoh E., Gustafsson J. A., Poellinger L., Nilsson S. High level expression of functional full length and truncated glucocorticoid receptor in Chinese hamster ovary cells. Demonstration of ligand-induced down-regulation of expressed receptor mRNA and protein. J Biol Chem. 1991 Jun 5;266(16):10078–10085. [PubMed] [Google Scholar]
- Andersson S., Davis D. L., Dahlbäck H., Jörnvall H., Russell D. W. Cloning, structure, and expression of the mitochondrial cytochrome P-450 sterol 26-hydroxylase, a bile acid biosynthetic enzyme. J Biol Chem. 1989 May 15;264(14):8222–8229. [PubMed] [Google Scholar]
- Beato M. Gene regulation by steroid hormones. Cell. 1989 Feb 10;56(3):335–344. doi: 10.1016/0092-8674(89)90237-7. [DOI] [PubMed] [Google Scholar]
- Berghard A., Gradin K., Pongratz I., Whitelaw M., Poellinger L. Cross-coupling of signal transduction pathways: the dioxin receptor mediates induction of cytochrome P-450IA1 expression via a protein kinase C-dependent mechanism. Mol Cell Biol. 1993 Jan;13(1):677–689. doi: 10.1128/mcb.13.1.677. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bresnick E. H., Dalman F. C., Sanchez E. R., Pratt W. B. Evidence that the 90-kDa heat shock protein is necessary for the steroid binding conformation of the L cell glucocorticoid receptor. J Biol Chem. 1989 Mar 25;264(9):4992–4997. [PubMed] [Google Scholar]
- Burbach K. M., Poland A., Bradfield C. A. Cloning of the Ah-receptor cDNA reveals a distinctive ligand-activated transcription factor. Proc Natl Acad Sci U S A. 1992 Sep 1;89(17):8185–8189. doi: 10.1073/pnas.89.17.8185. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carrier F., Owens R. A., Nebert D. W., Puga A. Dioxin-dependent activation of murine Cyp1a-1 gene transcription requires protein kinase C-dependent phosphorylation. Mol Cell Biol. 1992 Apr;12(4):1856–1863. doi: 10.1128/mcb.12.4.1856. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chakraborti P. K., Garabedian M. J., Yamamoto K. R., Simons S. S., Jr Role of cysteines 640, 656, and 661 in steroid binding to rat glucocorticoid receptors. J Biol Chem. 1992 Jun 5;267(16):11366–11373. [PubMed] [Google Scholar]
- Courey A. J., Tjian R. Analysis of Sp1 in vivo reveals multiple transcriptional domains, including a novel glutamine-rich activation motif. Cell. 1988 Dec 2;55(5):887–898. doi: 10.1016/0092-8674(88)90144-4. [DOI] [PubMed] [Google Scholar]
- Cuthill S., Wilhelmsson A., Poellinger L. Role of the ligand in intracellular receptor function: receptor affinity determines activation in vitro of the latent dioxin receptor to a DNA-binding form. Mol Cell Biol. 1991 Jan;11(1):401–411. doi: 10.1128/mcb.11.1.401. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Denis M., Poellinger L., Wikstöm A. C., Gustafsson J. A. Requirement of hormone for thermal conversion of the glucocorticoid receptor to a DNA-binding state. Nature. 1988 Jun 16;333(6174):686–688. doi: 10.1038/333686a0. [DOI] [PubMed] [Google Scholar]
- Denison M. S., Fisher J. M., Whitlock J. P., Jr Inducible, receptor-dependent protein-DNA interactions at a dioxin-responsive transcriptional enhancer. Proc Natl Acad Sci U S A. 1988 Apr;85(8):2528–2532. doi: 10.1073/pnas.85.8.2528. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eilers M., Picard D., Yamamoto K. R., Bishop J. M. Chimaeras of myc oncoprotein and steroid receptors cause hormone-dependent transformation of cells. Nature. 1989 Jul 6;340(6228):66–68. doi: 10.1038/340066a0. [DOI] [PubMed] [Google Scholar]
- Ema M., Sogawa K., Watanabe N., Chujoh Y., Matsushita N., Gotoh O., Funae Y., Fujii-Kuriyama Y. cDNA cloning and structure of mouse putative Ah receptor. Biochem Biophys Res Commun. 1992 Apr 15;184(1):246–253. doi: 10.1016/0006-291x(92)91185-s. [DOI] [PubMed] [Google Scholar]
- Fujisawa-Sehara A., Yamane M., Fujii-Kuriyama Y. A DNA-binding factor specific for xenobiotic responsive elements of P-450c gene exists as a cryptic form in cytoplasm: its possible translocation to nucleus. Proc Natl Acad Sci U S A. 1988 Aug;85(16):5859–5863. doi: 10.1073/pnas.85.16.5859. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gasiewicz T. A., Neal R. A. The examination and quantitation of tissue cytosolic receptors for 2,3,7,8-tetrachlorodibenzo-p-dioxin using hydroxylapatite. Anal Biochem. 1982 Jul 15;124(1):1–11. doi: 10.1016/0003-2697(82)90212-3. [DOI] [PubMed] [Google Scholar]
- Gerster T., Balmaceda C. G., Roeder R. G. The cell type-specific octamer transcription factor OTF-2 has two domains required for the activation of transcription. EMBO J. 1990 May;9(5):1635–1643. doi: 10.1002/j.1460-2075.1990.tb08283.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Giguère V., Hollenberg S. M., Rosenfeld M. G., Evans R. M. Functional domains of the human glucocorticoid receptor. Cell. 1986 Aug 29;46(5):645–652. doi: 10.1016/0092-8674(86)90339-9. [DOI] [PubMed] [Google Scholar]
- Godowski P. J., Rusconi S., Miesfeld R., Yamamoto K. R. Glucocorticoid receptor mutants that are constitutive activators of transcriptional enhancement. Nature. 1987 Jan 22;325(6102):365–368. doi: 10.1038/325365a0. [DOI] [PubMed] [Google Scholar]
- Green S., Chambon P. Nuclear receptors enhance our understanding of transcription regulation. Trends Genet. 1988 Nov;4(11):309–314. doi: 10.1016/0168-9525(88)90108-4. [DOI] [PubMed] [Google Scholar]
- Göttlicher M., Widmark E., Li Q., Gustafsson J. A. Fatty acids activate a chimera of the clofibric acid-activated receptor and the glucocorticoid receptor. Proc Natl Acad Sci U S A. 1992 May 15;89(10):4653–4657. doi: 10.1073/pnas.89.10.4653. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hapgood J., Cuthill S., Denis M., Poellinger L., Gustafsson J. A. Specific protein-DNA interactions at a xenobiotic-responsive element: copurification of dioxin receptor and DNA-binding activity. Proc Natl Acad Sci U S A. 1989 Jan;86(1):60–64. doi: 10.1073/pnas.86.1.60. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hoffman E. C., Reyes H., Chu F. F., Sander F., Conley L. H., Brooks B. A., Hankinson O. Cloning of a factor required for activity of the Ah (dioxin) receptor. Science. 1991 May 17;252(5008):954–958. doi: 10.1126/science.1852076. [DOI] [PubMed] [Google Scholar]
- Hollenberg S. M., Evans R. M. Multiple and cooperative trans-activation domains of the human glucocorticoid receptor. Cell. 1988 Dec 2;55(5):899–906. doi: 10.1016/0092-8674(88)90145-6. [DOI] [PubMed] [Google Scholar]
- Hollenberg S. M., Giguere V., Segui P., Evans R. M. Colocalization of DNA-binding and transcriptional activation functions in the human glucocorticoid receptor. Cell. 1987 Apr 10;49(1):39–46. doi: 10.1016/0092-8674(87)90753-7. [DOI] [PubMed] [Google Scholar]
- Hwang J. J., Chambon P., Davidson I. Characterization of the transcription activation function and the DNA binding domain of transcriptional enhancer factor-1. EMBO J. 1993 Jun;12(6):2337–2348. doi: 10.1002/j.1460-2075.1993.tb05888.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Härd T., Kellenbach E., Boelens R., Maler B. A., Dahlman K., Freedman L. P., Carlstedt-Duke J., Yamamoto K. R., Gustafsson J. A., Kaptein R. Solution structure of the glucocorticoid receptor DNA-binding domain. Science. 1990 Jul 13;249(4965):157–160. doi: 10.1126/science.2115209. [DOI] [PubMed] [Google Scholar]
- Kadesch T. Consequences of heteromeric interactions among helix-loop-helix proteins. Cell Growth Differ. 1993 Jan;4(1):49–55. [PubMed] [Google Scholar]
- Luisi B. F., Xu W. X., Otwinowski Z., Freedman L. P., Yamamoto K. R., Sigler P. B. Crystallographic analysis of the interaction of the glucocorticoid receptor with DNA. Nature. 1991 Aug 8;352(6335):497–505. doi: 10.1038/352497a0. [DOI] [PubMed] [Google Scholar]
- Müller-Immerglück M. M., Schaffner W., Matthias P. Transcription factor Oct-2A contains functionally redundant activating domains and works selectively from a promoter but not from a remote enhancer position in non-lymphoid (HeLa) cells. EMBO J. 1990 May;9(5):1625–1634. doi: 10.1002/j.1460-2075.1990.tb08282.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nemoto T., Mason G. G., Wilhelmsson A., Cuthill S., Hapgood J., Gustafsson J. A., Poellinger L. Activation of the dioxin and glucocorticoid receptors to a DNA binding state under cell-free conditions. J Biol Chem. 1990 Feb 5;265(4):2269–2277. [PubMed] [Google Scholar]
- Neuhold L. A., Shirayoshi Y., Ozato K., Jones J. E., Nebert D. W. Regulation of mouse CYP1A1 gene expression by dioxin: requirement of two cis-acting elements during induction. Mol Cell Biol. 1989 Jun;9(6):2378–2386. doi: 10.1128/mcb.9.6.2378. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Perdew G. H. Association of the Ah receptor with the 90-kDa heat shock protein. J Biol Chem. 1988 Sep 25;263(27):13802–13805. [PubMed] [Google Scholar]
- Perdew G. H., Whitelaw M. L. Evidence that the 90-kDa heat shock protein (HSP90) exists in cytosol in heteromeric complexes containing HSP70 and three other proteins with Mr of 63,000, 56,000, and 50,000. J Biol Chem. 1991 Apr 15;266(11):6708–6713. [PubMed] [Google Scholar]
- Picard D., Khursheed B., Garabedian M. J., Fortin M. G., Lindquist S., Yamamoto K. R. Reduced levels of hsp90 compromise steroid receptor action in vivo. Nature. 1990 Nov 8;348(6297):166–168. doi: 10.1038/348166a0. [DOI] [PubMed] [Google Scholar]
- Picard D., Salser S. J., Yamamoto K. R. A movable and regulable inactivation function within the steroid binding domain of the glucocorticoid receptor. Cell. 1988 Sep 23;54(7):1073–1080. doi: 10.1016/0092-8674(88)90122-5. [DOI] [PubMed] [Google Scholar]
- Picard D., Yamamoto K. R. Two signals mediate hormone-dependent nuclear localization of the glucocorticoid receptor. EMBO J. 1987 Nov;6(11):3333–3340. doi: 10.1002/j.1460-2075.1987.tb02654.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Poellinger L., Göttlicher M., Gustafsson J. A. The dioxin and peroxisome proliferator-activated receptors: nuclear receptors in search of endogenous ligands. Trends Pharmacol Sci. 1992 Jun;13(6):241–245. doi: 10.1016/0165-6147(92)90076-i. [DOI] [PubMed] [Google Scholar]
- Poellinger L., Lund J., Dahlberg E., Gustafsson J. A. A hydroxylapatite microassay for receptor binding of 2,3,7,8-tetrachlorodibenzo-p-dioxin and 3-methylcholanthrene in various target tissues. Anal Biochem. 1985 Feb 1;144(2):371–384. doi: 10.1016/0003-2697(85)90130-7. [DOI] [PubMed] [Google Scholar]
- Poland A., Knutson J. C. 2,3,7,8-tetrachlorodibenzo-p-dioxin and related halogenated aromatic hydrocarbons: examination of the mechanism of toxicity. Annu Rev Pharmacol Toxicol. 1982;22:517–554. doi: 10.1146/annurev.pa.22.040182.002505. [DOI] [PubMed] [Google Scholar]
- Pongratz I., Mason G. G., Poellinger L. Dual roles of the 90-kDa heat shock protein hsp90 in modulating functional activities of the dioxin receptor. Evidence that the dioxin receptor functionally belongs to a subclass of nuclear receptors which require hsp90 both for ligand binding activity and repression of intrinsic DNA binding activity. J Biol Chem. 1992 Jul 5;267(19):13728–13734. [PubMed] [Google Scholar]
- Reyes H., Reisz-Porszasz S., Hankinson O. Identification of the Ah receptor nuclear translocator protein (Arnt) as a component of the DNA binding form of the Ah receptor. Science. 1992 May 22;256(5060):1193–1195. doi: 10.1126/science.256.5060.1193. [DOI] [PubMed] [Google Scholar]
- Shaknovich R., Shue G., Kohtz D. S. Conformational activation of a basic helix-loop-helix protein (MyoD1) by the C-terminal region of murine HSP90 (HSP84). Mol Cell Biol. 1992 Nov;12(11):5059–5068. doi: 10.1128/mcb.12.11.5059. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith D. F., Toft D. O. Steroid receptors and their associated proteins. Mol Endocrinol. 1993 Jan;7(1):4–11. doi: 10.1210/mend.7.1.8446107. [DOI] [PubMed] [Google Scholar]
- Strömstedt P. E., Berkenstam A., Jörnvall H., Gustafsson J. A., Carlstedt-Duke J. Radiosequence analysis of the human progestin receptor charged with [3H]promegestone. A comparison with the glucocorticoid receptor. J Biol Chem. 1990 Aug 5;265(22):12973–12977. [PubMed] [Google Scholar]
- Takahashi J. S. Circadian clock genes are ticking. Science. 1992 Oct 9;258(5080):238–240. doi: 10.1126/science.1384127. [DOI] [PubMed] [Google Scholar]
- Tora L., White J., Brou C., Tasset D., Webster N., Scheer E., Chambon P. The human estrogen receptor has two independent nonacidic transcriptional activation functions. Cell. 1989 Nov 3;59(3):477–487. doi: 10.1016/0092-8674(89)90031-7. [DOI] [PubMed] [Google Scholar]
- Webster N. J., Green S., Jin J. R., Chambon P. The hormone-binding domains of the estrogen and glucocorticoid receptors contain an inducible transcription activation function. Cell. 1988 Jul 15;54(2):199–207. doi: 10.1016/0092-8674(88)90552-1. [DOI] [PubMed] [Google Scholar]
- Whitelaw M., Pongratz I., Wilhelmsson A., Gustafsson J. A., Poellinger L. Ligand-dependent recruitment of the Arnt coregulator determines DNA recognition by the dioxin receptor. Mol Cell Biol. 1993 Apr;13(4):2504–2514. doi: 10.1128/mcb.13.4.2504. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wiech H., Buchner J., Zimmermann R., Jakob U. Hsp90 chaperones protein folding in vitro. Nature. 1992 Jul 9;358(6382):169–170. doi: 10.1038/358169a0. [DOI] [PubMed] [Google Scholar]
- Wilhelmsson A., Cuthill S., Denis M., Wikström A. C., Gustafsson J. A., Poellinger L. The specific DNA binding activity of the dioxin receptor is modulated by the 90 kd heat shock protein. EMBO J. 1990 Jan;9(1):69–76. doi: 10.1002/j.1460-2075.1990.tb08081.x. [DOI] [PMC free article] [PubMed] [Google Scholar]