Abstract
We have identified and characterized a novel human estrogen receptor (ER) beta isoform, ERbetacx, which is truncated at the C-terminal region but has an extra 26 amino acids due to alternative splicing. The ERbetacx transcript is expressed in testis, ovary, thymus and prostate as well as in human cultured cell lines such as HEC-1, HOS-TE85 and Saos-2 cells. ERbetacx protein is also immunodetectable in these human cells. Biochemical analysis reveals that the average dissociation constants ( K d) of ERalpha and ERbeta for 17beta-estradiol (E2) are 0.2 and 0.6 nM respectively, but ERbetacx has no ligand binding ability. ERalpha and ERbeta proteins bind to the estrogen response element, whereas ERbetacx does not form any shifted complex in gel shift assays. In a transient expression assay, ERbetacx shows no ligand-dependent transactivation ability of a basal promoter and also cannot interact with a cofactor, TIF1alpha, in the presence or absence of E2. ERbetacx preferentially forms a heterodimer with ERalpha rather than that with ERbeta, inhibiting DNA binding by ERalpha. Interestingly, however, it shows a significant dominant negative activity only against ERalpha transactivation. Thus, this study indicates that ERbetacx potentially inhibits ERalpha-mediated estrogen action and that alternative splicing of the C-terminal region and its inhibitory properties are characteristic of several members of nuclear receptor isoforms.
Full Text
The Full Text of this article is available as a PDF (243.7 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Breathnach R., Chambon P. Organization and expression of eucaryotic split genes coding for proteins. Annu Rev Biochem. 1981;50:349–383. doi: 10.1146/annurev.bi.50.070181.002025. [DOI] [PubMed] [Google Scholar]
- Byers M., Kuiper G. G., Gustafsson J. A., Park-Sarge O. K. Estrogen receptor-beta mRNA expression in rat ovary: down-regulation by gonadotropins. Mol Endocrinol. 1997 Feb;11(2):172–182. doi: 10.1210/mend.11.2.9887. [DOI] [PubMed] [Google Scholar]
- Chu S., Fuller P. J. Identification of a splice variant of the rat estrogen receptor beta gene. Mol Cell Endocrinol. 1997 Sep 19;132(1-2):195–199. doi: 10.1016/s0303-7207(97)00133-0. [DOI] [PubMed] [Google Scholar]
- Cowley S. M., Hoare S., Mosselman S., Parker M. G. Estrogen receptors alpha and beta form heterodimers on DNA. J Biol Chem. 1997 Aug 8;272(32):19858–19862. doi: 10.1074/jbc.272.32.19858. [DOI] [PubMed] [Google Scholar]
- Danielian P. S., White R., Lees J. A., Parker M. G. Identification of a conserved region required for hormone dependent transcriptional activation by steroid hormone receptors. EMBO J. 1992 Mar;11(3):1025–1033. doi: 10.1002/j.1460-2075.1992.tb05141.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dotzlaw H., Leygue E., Watson P. H., Murphy L. C. Expression of estrogen receptor-beta in human breast tumors. J Clin Endocrinol Metab. 1997 Jul;82(7):2371–2374. doi: 10.1210/jcem.82.7.4212. [DOI] [PubMed] [Google Scholar]
- Durand B., Saunders M., Gaudon C., Roy B., Losson R., Chambon P. Activation function 2 (AF-2) of retinoic acid receptor and 9-cis retinoic acid receptor: presence of a conserved autonomous constitutive activating domain and influence of the nature of the response element on AF-2 activity. EMBO J. 1994 Nov 15;13(22):5370–5382. doi: 10.1002/j.1460-2075.1994.tb06872.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ebihara K., Masuhiro Y., Kitamoto T., Suzawa M., Uematsu Y., Yoshizawa T., Ono T., Harada H., Matsuda K., Hasegawa T. Intron retention generates a novel isoform of the murine vitamin D receptor that acts in a dominant negative way on the vitamin D signaling pathway. Mol Cell Biol. 1996 Jul;16(7):3393–3400. doi: 10.1128/mcb.16.7.3393. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ekena K., Weis K. E., Katzenellenbogen J. A., Katzenellenbogen B. S. Identification of amino acids in the hormone binding domain of the human estrogen receptor important in estrogen binding. J Biol Chem. 1996 Aug 16;271(33):20053–20059. doi: 10.1074/jbc.271.33.20053. [DOI] [PubMed] [Google Scholar]
- Enmark E., Pelto-Huikko M., Grandien K., Lagercrantz S., Lagercrantz J., Fried G., Nordenskjöld M., Gustafsson J. A. Human estrogen receptor beta-gene structure, chromosomal localization, and expression pattern. J Clin Endocrinol Metab. 1997 Dec;82(12):4258–4265. doi: 10.1210/jcem.82.12.4470. [DOI] [PubMed] [Google Scholar]
- Evans R. M. The steroid and thyroid hormone receptor superfamily. Science. 1988 May 13;240(4854):889–895. doi: 10.1126/science.3283939. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Graham F. L., van der Eb A. J. A new technique for the assay of infectivity of human adenovirus 5 DNA. Virology. 1973 Apr;52(2):456–467. doi: 10.1016/0042-6822(73)90341-3. [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]
- Ince B. A., Zhuang Y., Wrenn C. K., Shapiro D. J., Katzenellenbogen B. S. Powerful dominant negative mutants of the human estrogen receptor. J Biol Chem. 1993 Jul 5;268(19):14026–14032. [PubMed] [Google Scholar]
- Inoue S., Hoshino S., Miyoshi H., Akishita M., Hosoi T., Orimo H., Ouchi Y. Identification of a novel isoform of estrogen receptor, a potential inhibitor of estrogen action, in vascular smooth muscle cells. Biochem Biophys Res Commun. 1996 Feb 27;219(3):766–772. doi: 10.1006/bbrc.1996.0308. [DOI] [PubMed] [Google Scholar]
- Inoue S., Kondo S., Hashimoto M., Kondo T., Muramatsu M. Isolation of estrogen receptor-binding sites in human genomic DNA. Nucleic Acids Res. 1991 Aug 11;19(15):4091–4096. doi: 10.1093/nar/19.15.4091. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Inoue S., Orimo A., Hosoi T., Kondo S., Toyoshima H., Kondo T., Ikegami A., Ouchi Y., Orimo H., Muramatsu M. Genomic binding-site cloning reveals an estrogen-responsive gene that encodes a RING finger protein. Proc Natl Acad Sci U S A. 1993 Dec 1;90(23):11117–11121. doi: 10.1073/pnas.90.23.11117. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kastner P., Krust A., Mendelsohn C., Garnier J. M., Zelent A., Leroy P., Staub A., Chambon P. Murine isoforms of retinoic acid receptor gamma with specific patterns of expression. Proc Natl Acad Sci U S A. 1990 Apr;87(7):2700–2704. doi: 10.1073/pnas.87.7.2700. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klein-Hitpass L., Schorpp M., Wagner U., Ryffel G. U. An estrogen-responsive element derived from the 5' flanking region of the Xenopus vitellogenin A2 gene functions in transfected human cells. Cell. 1986 Sep 26;46(7):1053–1061. doi: 10.1016/0092-8674(86)90705-1. [DOI] [PubMed] [Google Scholar]
- Koenig R. J., Lazar M. A., Hodin R. A., Brent G. A., Larsen P. R., Chin W. W., Moore D. D. Inhibition of thyroid hormone action by a non-hormone binding c-erbA protein generated by alternative mRNA splicing. Nature. 1989 Feb 16;337(6208):659–661. doi: 10.1038/337659a0. [DOI] [PubMed] [Google Scholar]
- Koike S., Sakai M., Muramatsu M. Molecular cloning and characterization of rat estrogen receptor cDNA. Nucleic Acids Res. 1987 Mar 25;15(6):2499–2513. doi: 10.1093/nar/15.6.2499. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kozak M. The scanning model for translation: an update. J Cell Biol. 1989 Feb;108(2):229–241. doi: 10.1083/jcb.108.2.229. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuiper G. G., Carlsson B., Grandien K., Enmark E., Häggblad J., Nilsson S., Gustafsson J. A. Comparison of the ligand binding specificity and transcript tissue distribution of estrogen receptors alpha and beta. Endocrinology. 1997 Mar;138(3):863–870. doi: 10.1210/endo.138.3.4979. [DOI] [PubMed] [Google Scholar]
- Kuiper G. G., Enmark E., Pelto-Huikko M., Nilsson S., Gustafsson J. A. Cloning of a novel receptor expressed in rat prostate and ovary. Proc Natl Acad Sci U S A. 1996 Jun 11;93(12):5925–5930. doi: 10.1073/pnas.93.12.5925. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Le Douarin B., Nielsen A. L., Garnier J. M., Ichinose H., Jeanmougin F., Losson R., Chambon P. A possible involvement of TIF1 alpha and TIF1 beta in the epigenetic control of transcription by nuclear receptors. EMBO J. 1996 Dec 2;15(23):6701–6715. [PMC free article] [PubMed] [Google Scholar]
- Le Douarin B., Zechel C., Garnier J. M., Lutz Y., Tora L., Pierrat P., Heery D., Gronemeyer H., Chambon P., Losson R. The N-terminal part of TIF1, a putative mediator of the ligand-dependent activation function (AF-2) of nuclear receptors, is fused to B-raf in the oncogenic protein T18. EMBO J. 1995 May 1;14(9):2020–2033. doi: 10.1002/j.1460-2075.1995.tb07194.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leroy P., Krust A., Zelent A., Mendelsohn C., Garnier J. M., Kastner P., Dierich A., Chambon P. Multiple isoforms of the mouse retinoic acid receptor alpha are generated by alternative splicing and differential induction by retinoic acid. EMBO J. 1991 Jan;10(1):59–69. doi: 10.1002/j.1460-2075.1991.tb07921.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meyer M. E., Gronemeyer H., Turcotte B., Bocquel M. T., Tasset D., Chambon P. Steroid hormone receptors compete for factors that mediate their enhancer function. Cell. 1989 May 5;57(3):433–442. doi: 10.1016/0092-8674(89)90918-5. [DOI] [PubMed] [Google Scholar]
- Mosselman S., Polman J., Dijkema R. ER beta: identification and characterization of a novel human estrogen receptor. FEBS Lett. 1996 Aug 19;392(1):49–53. doi: 10.1016/0014-5793(96)00782-x. [DOI] [PubMed] [Google Scholar]
- Niwa H., Yamamura K., Miyazaki J. Efficient selection for high-expression transfectants with a novel eukaryotic vector. Gene. 1991 Dec 15;108(2):193–199. doi: 10.1016/0378-1119(91)90434-d. [DOI] [PubMed] [Google Scholar]
- Oakley R. H., Sar M., Cidlowski J. A. The human glucocorticoid receptor beta isoform. Expression, biochemical properties, and putative function. J Biol Chem. 1996 Apr 19;271(16):9550–9559. doi: 10.1074/jbc.271.16.9550. [DOI] [PubMed] [Google Scholar]
- Ogawa S., Inoue S., Watanabe T., Hiroi H., Orimo A., Hosoi T., Ouchi Y., Muramatsu M. The complete primary structure of human estrogen receptor beta (hER beta) and its heterodimerization with ER alpha in vivo and in vitro. Biochem Biophys Res Commun. 1998 Feb 4;243(1):122–126. doi: 10.1006/bbrc.1997.7893. [DOI] [PubMed] [Google Scholar]
- Orimo A., Inoue S., Ikeda K., Noji S., Muramatsu M. Molecular cloning, structure, and expression of mouse estrogen-responsive finger protein Efp. Co-localization with estrogen receptor mRNA in target organs. J Biol Chem. 1995 Oct 13;270(41):24406–24413. doi: 10.1074/jbc.270.41.24406. [DOI] [PubMed] [Google Scholar]
- Schodin D. J., Zhuang Y., Shapiro D. J., Katzenellenbogen B. S. Analysis of mechanisms that determine dominant negative estrogen receptor effectiveness. J Biol Chem. 1995 Dec 29;270(52):31163–31171. doi: 10.1074/jbc.270.52.31163. [DOI] [PubMed] [Google Scholar]
- Sharp P. A. Splicing of messenger RNA precursors. Science. 1987 Feb 13;235(4790):766–771. doi: 10.1126/science.3544217. [DOI] [PubMed] [Google Scholar]
- Tasset D., Tora L., Fromental C., Scheer E., Chambon P. Distinct classes of transcriptional activating domains function by different mechanisms. Cell. 1990 Sep 21;62(6):1177–1187. doi: 10.1016/0092-8674(90)90394-t. [DOI] [PubMed] [Google Scholar]
- Tremblay G. B., Tremblay A., Copeland N. G., Gilbert D. J., Jenkins N. A., Labrie F., Giguère V. Cloning, chromosomal localization, and functional analysis of the murine estrogen receptor beta. Mol Endocrinol. 1997 Mar;11(3):353–365. doi: 10.1210/mend.11.3.9902. [DOI] [PubMed] [Google Scholar]
- Vladusic E. A., Hornby A. E., Guerra-Vladusic F. K., Lupu R. Expression of estrogen receptor beta messenger RNA variant in breast cancer. Cancer Res. 1998 Jan 15;58(2):210–214. [PubMed] [Google Scholar]
- Wang Y., Miksicek R. J. Identification of a dominant negative form of the human estrogen receptor. Mol Endocrinol. 1991 Nov;5(11):1707–1715. doi: 10.1210/mend-5-11-1707. [DOI] [PubMed] [Google Scholar]
- Watanabe T., Inoue S., Ogawa S., Ishii Y., Hiroi H., Ikeda K., Orimo A., Muramatsu M. Agonistic effect of tamoxifen is dependent on cell type, ERE-promoter context, and estrogen receptor subtype: functional difference between estrogen receptors alpha and beta. Biochem Biophys Res Commun. 1997 Jul 9;236(1):140–145. doi: 10.1006/bbrc.1997.6915. [DOI] [PubMed] [Google Scholar]
- Zelent A., Mendelsohn C., Kastner P., Krust A., Garnier J. M., Ruffenach F., Leroy P., Chambon P. Differentially expressed isoforms of the mouse retinoic acid receptor beta generated by usage of two promoters and alternative splicing. EMBO J. 1991 Jan;10(1):71–81. doi: 10.1002/j.1460-2075.1991.tb07922.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhang Q. X., Borg A., Fuqua S. A. An exon 5 deletion variant of the estrogen receptor frequently coexpressed with wild-type estrogen receptor in human breast cancer. Cancer Res. 1993 Dec 15;53(24):5882–5884. [PubMed] [Google Scholar]