Abstract
PRH (proline-rich homeodomain protein)/Hex is important in the control of cell proliferation and differentiation. We have shown previously that PRH contains two domains that can bring about transcriptional repression independently; the PRH homeodomain represses transcription by binding to TATA box sequences, whereas the proline-rich N-terminal domain can repress transcription by interacting with members of the Groucho/TLE (transducin-like enhancer of split) family of co-repressor proteins. The proteasome is a multi-subunit protein complex involved in the processing and degradation of proteins. Some proteasome subunits have been suggested to play a role in the regulation of transcription. In the present study, we show that PRH interacts with the HC8 subunit of the proteasome in the context of both 20 and 26 S proteasomes. Moreover, we show that PRH is associated with the proteasome in haematopoietic cells and that the proline-rich PRH N-terminal domain is responsible for this interaction. Whereas PRH can be cleaved by the proteasome, it does not appear to be degraded rapidly in vitro or in vivo, and the proteolytic activity of the proteasome is not required for transcriptional repression by PRH. However, proteasomal digestion of PRH can liberate truncated PRH proteins that retain the ability to bind to DNA. We discuss these findings in terms of the biological role of PRH in gene regulation and the control of cell proliferation.
Full Text
The Full Text of this article is available as a PDF (224.3 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bedford F. K., Ashworth A., Enver T., Wiedemann L. M. HEX: a novel homeobox gene expressed during haematopoiesis and conserved between mouse and human. Nucleic Acids Res. 1993 Mar 11;21(5):1245–1249. doi: 10.1093/nar/21.5.1245. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Boddy M. N., Duprez E., Borden K. L., Freemont P. S. Surface residue mutations of the PML RING finger domain alter the formation of nuclear matrix-associated PML bodies. J Cell Sci. 1997 Sep;110(Pt 18):2197–2205. doi: 10.1242/jcs.110.18.2197. [DOI] [PubMed] [Google Scholar]
- Borden Katherine L. B. Pondering the promyelocytic leukemia protein (PML) puzzle: possible functions for PML nuclear bodies. Mol Cell Biol. 2002 Aug;22(15):5259–5269. doi: 10.1128/MCB.22.15.5259-5269.2002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brickman J. M., Jones C. M., Clements M., Smith J. C., Beddington R. S. Hex is a transcriptional repressor that contributes to anterior identity and suppresses Spemann organiser function. Development. 2000 Jun;127(11):2303–2315. doi: 10.1242/dev.127.11.2303. [DOI] [PubMed] [Google Scholar]
- Brown M. S., Ye J., Rawson R. B., Goldstein J. L. Regulated intramembrane proteolysis: a control mechanism conserved from bacteria to humans. Cell. 2000 Feb 18;100(4):391–398. doi: 10.1016/s0092-8674(00)80675-3. [DOI] [PubMed] [Google Scholar]
- Butcher Amy J., Gaston Kevin, Jayaraman Padma-Sheela. Purification of the proline-rich homeodomain protein. J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Mar 25;786(1-2):3–6. doi: 10.1016/s1570-0232(02)00740-7. [DOI] [PubMed] [Google Scholar]
- Chang K. S., Fan Y. H., Andreeff M., Liu J., Mu Z. M. The PML gene encodes a phosphoprotein associated with the nuclear matrix. Blood. 1995 Jun 15;85(12):3646–3653. [PubMed] [Google Scholar]
- Chang Y. C., Lee Y. S., Tejima T., Tanaka K., Omura S., Heintz N. H., Mitsui Y., Magae J. mdm2 and bax, downstream mediators of the p53 response, are degraded by the ubiquitin-proteasome pathway. Cell Growth Differ. 1998 Jan;9(1):79–84. [PubMed] [Google Scholar]
- Ciechanover A. The ubiquitin-proteasome pathway: on protein death and cell life. EMBO J. 1998 Dec 15;17(24):7151–7160. doi: 10.1093/emboj/17.24.7151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Crompton M. R., Bartlett T. J., MacGregor A. D., Manfioletti G., Buratti E., Giancotti V., Goodwin G. H. Identification of a novel vertebrate homeobox gene expressed in haematopoietic cells. Nucleic Acids Res. 1992 Nov 11;20(21):5661–5667. doi: 10.1093/nar/20.21.5661. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fan C. M., Maniatis T. Generation of p50 subunit of NF-kappa B by processing of p105 through an ATP-dependent pathway. Nature. 1991 Dec 5;354(6352):395–398. doi: 10.1038/354395a0. [DOI] [PubMed] [Google Scholar]
- Ferdous A., Gonzalez F., Sun L., Kodadek T., Johnston S. A. The 19S regulatory particle of the proteasome is required for efficient transcription elongation by RNA polymerase II. Mol Cell. 2001 May;7(5):981–991. doi: 10.1016/s1097-2765(01)00250-7. [DOI] [PubMed] [Google Scholar]
- Ferrell K., Wilkinson C. R., Dubiel W., Gordon C. Regulatory subunit interactions of the 26S proteasome, a complex problem. Trends Biochem Sci. 2000 Feb;25(2):83–88. doi: 10.1016/s0968-0004(99)01529-7. [DOI] [PubMed] [Google Scholar]
- Fields S., Song O. A novel genetic system to detect protein-protein interactions. Nature. 1989 Jul 20;340(6230):245–246. doi: 10.1038/340245a0. [DOI] [PubMed] [Google Scholar]
- Gerards W. L., Enzlin J., Häner M., Hendriks I. L., Aebi U., Bloemendal H., Boelens W. The human alpha-type proteasomal subunit HsC8 forms a double ringlike structure, but does not assemble into proteasome-like particles with the beta-type subunits HsDelta or HsBPROS26. J Biol Chem. 1997 Apr 11;272(15):10080–10086. doi: 10.1074/jbc.272.15.10080. [DOI] [PubMed] [Google Scholar]
- Gerards W. L., de Jong W. W., Bloemendal H., Boelens W. The human proteasomal subunit HsC8 induces ring formation of other alpha-type subunits. J Mol Biol. 1998 Jan 9;275(1):113–121. doi: 10.1006/jmbi.1997.1429. [DOI] [PubMed] [Google Scholar]
- Gonzalez Fernando, Delahodde Agnes, Kodadek Thomas, Johnston Stephen Albert. Recruitment of a 19S proteasome subcomplex to an activated promoter. Science. 2002 Apr 19;296(5567):548–550. doi: 10.1126/science.1069490. [DOI] [PubMed] [Google Scholar]
- Gossen M., Bujard H. Tight control of gene expression in mammalian cells by tetracycline-responsive promoters. Proc Natl Acad Sci U S A. 1992 Jun 15;89(12):5547–5551. doi: 10.1073/pnas.89.12.5547. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Guiral M., Bess K., Goodwin G., Jayaraman P. S. PRH represses transcription in hematopoietic cells by at least two independent mechanisms. J Biol Chem. 2000 Oct 27;276(4):2961–2970. doi: 10.1074/jbc.M004948200. [DOI] [PubMed] [Google Scholar]
- Hoppe T., Matuschewski K., Rape M., Schlenker S., Ulrich H. D., Jentsch S. Activation of a membrane-bound transcription factor by regulated ubiquitin/proteasome-dependent processing. Cell. 2000 Sep 1;102(5):577–586. doi: 10.1016/s0092-8674(00)00080-5. [DOI] [PubMed] [Google Scholar]
- Javed A., Guo B., Hiebert S., Choi J. Y., Green J., Zhao S. C., Osborne M. A., Stifani S., Stein J. L., Lian J. B. Groucho/TLE/R-esp proteins associate with the nuclear matrix and repress RUNX (CBF(alpha)/AML/PEBP2(alpha)) dependent activation of tissue-specific gene transcription. J Cell Sci. 2000 Jun;113(Pt 12):2221–2231. doi: 10.1242/jcs.113.12.2221. [DOI] [PubMed] [Google Scholar]
- Jayaraman P. S., Frampton J., Goodwin G. The homeodomain protein PRH influences the differentiation of haematopoietic cells. Leuk Res. 2000 Dec;24(12):1023–1031. doi: 10.1016/s0145-2126(00)00072-2. [DOI] [PubMed] [Google Scholar]
- Jones C. M., Broadbent J., Thomas P. Q., Smith J. C., Beddington R. S. An anterior signalling centre in Xenopus revealed by the homeobox gene XHex. Curr Biol. 1999 Sep 9;9(17):946–954. doi: 10.1016/s0960-9822(99)80421-7. [DOI] [PubMed] [Google Scholar]
- Lafarga Miguel, Berciano Maria Teresa, Pena Emma, Mayo Isabel, Castaño Jose G., Bohmann Dirk, Rodrigues João Pedro, Tavanez João Paulo, Carmo-Fonseca Maria. Clastosome: a subtype of nuclear body enriched in 19S and 20S proteasomes, ubiquitin, and protein substrates of proteasome. Mol Biol Cell. 2002 Aug;13(8):2771–2782. doi: 10.1091/mbc.E02-03-0122. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lallemand-Breitenbach V., Zhu J., Puvion F., Koken M., Honoré N., Doubeikovsky A., Duprez E., Pandolfi P. P., Puvion E., Freemont P. Role of promyelocytic leukemia (PML) sumolation in nuclear body formation, 11S proteasome recruitment, and As2O3-induced PML or PML/retinoic acid receptor alpha degradation. J Exp Med. 2001 Jun 18;193(12):1361–1371. doi: 10.1084/jem.193.12.1361. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maki C. G., Huibregtse J. M., Howley P. M. In vivo ubiquitination and proteasome-mediated degradation of p53(1). Cancer Res. 1996 Jun 1;56(11):2649–2654. [PubMed] [Google Scholar]
- Makino Y., Yoshida T., Yogosawa S., Tanaka K., Muramatsu M., Tamura T. A. Multiple mammalian proteasomal ATPases, but not proteasome itself, are associated with TATA-binding protein and a novel transcriptional activator, TIP120. Genes Cells. 1999 Sep;4(9):529–539. doi: 10.1046/j.1365-2443.1999.00277.x. [DOI] [PubMed] [Google Scholar]
- Martinez Barbera J. P., Clements M., Thomas P., Rodriguez T., Meloy D., Kioussis D., Beddington R. S. The homeobox gene Hex is required in definitive endodermal tissues for normal forebrain, liver and thyroid formation. Development. 2000 Jun;127(11):2433–2445. doi: 10.1242/dev.127.11.2433. [DOI] [PubMed] [Google Scholar]
- Molinari E., Gilman M., Natesan S. Proteasome-mediated degradation of transcriptional activators correlates with activation domain potency in vivo. EMBO J. 1999 Nov 15;18(22):6439–6447. doi: 10.1093/emboj/18.22.6439. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nawaz Z., Lonard D. M., Dennis A. P., Smith C. L., O'Malley B. W. Proteasome-dependent degradation of the human estrogen receptor. Proc Natl Acad Sci U S A. 1999 Mar 2;96(5):1858–1862. doi: 10.1073/pnas.96.5.1858. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newman C. S., Chia F., Krieg P. A. The XHex homeobox gene is expressed during development of the vascular endothelium: overexpression leads to an increase in vascular endothelial cell number. Mech Dev. 1997 Aug;66(1-2):83–93. doi: 10.1016/s0925-4773(97)00092-0. [DOI] [PubMed] [Google Scholar]
- Obinata Akiko, Akimoto Yoshihiro, Omoto Yasumasa, Hirano Hiroshi. Expression of Hex homeobox gene during skin development: Increase in epidermal cell proliferation by transfecting the Hex to the dermis. Dev Growth Differ. 2002 Aug;44(4):281–292. doi: 10.1046/j.1440-169x.2002.00642.x. [DOI] [PubMed] [Google Scholar]
- Pellizzari L., D'Elia A., Rustighi A., Manfioletti G., Tell G., Damante G. Expression and function of the homeodomain-containing protein Hex in thyroid cells. Nucleic Acids Res. 2000 Jul 1;28(13):2503–2511. doi: 10.1093/nar/28.13.2503. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ratner J. N., Balasubramanian B., Corden J., Warren S. L., Bregman D. B. Ultraviolet radiation-induced ubiquitination and proteasomal degradation of the large subunit of RNA polymerase II. Implications for transcription-coupled DNA repair. J Biol Chem. 1998 Feb 27;273(9):5184–5189. doi: 10.1074/jbc.273.9.5184. [DOI] [PubMed] [Google Scholar]
- Reidlinger J., Pike A. M., Savory P. J., Murray R. Z., Rivett A. J. Catalytic properties of 26 S and 20 S proteasomes and radiolabeling of MB1, LMP7, and C7 subunits associated with trypsin-like and chymotrypsin-like activities. J Biol Chem. 1997 Oct 3;272(40):24899–24905. doi: 10.1074/jbc.272.40.24899. [DOI] [PubMed] [Google Scholar]
- Rihs H. P., Peters R. Nuclear transport kinetics depend on phosphorylation-site-containing sequences flanking the karyophilic signal of the Simian virus 40 T-antigen. EMBO J. 1989 May;8(5):1479–1484. doi: 10.1002/j.1460-2075.1989.tb03531.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rivett A. J., Savory P. J., Djaballah H. Multicatalytic endopeptidase complex: proteasome. Methods Enzymol. 1994;244:331–350. doi: 10.1016/0076-6879(94)44026-3. [DOI] [PubMed] [Google Scholar]
- Salghetti S. E., Caudy A. A., Chenoweth J. G., Tansey W. P. Regulation of transcriptional activation domain function by ubiquitin. Science. 2001 Jul 19;293(5535):1651–1653. doi: 10.1126/science.1062079. [DOI] [PubMed] [Google Scholar]
- Salghetti S. E., Muratani M., Wijnen H., Futcher B., Tansey W. P. Functional overlap of sequences that activate transcription and signal ubiquitin-mediated proteolysis. Proc Natl Acad Sci U S A. 2000 Mar 28;97(7):3118–3123. doi: 10.1073/pnas.050007597. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tanaka T., Inazu T., Yamada K., Myint Z., Keng V. W., Inoue Y., Taniguchi N., Noguchi T. cDNA cloning and expression of rat homeobox gene, Hex, and functional characterization of the protein. Biochem J. 1999 Apr 1;339(Pt 1):111–117. [PMC free article] [PubMed] [Google Scholar]
- Thomas P. Q., Brown A., Beddington R. S. Hex: a homeobox gene revealing peri-implantation asymmetry in the mouse embryo and an early transient marker of endothelial cell precursors. Development. 1998 Jan;125(1):85–94. doi: 10.1242/dev.125.1.85. [DOI] [PubMed] [Google Scholar]
- Topcu Z., Mack D. L., Hromas R. A., Borden K. L. The promyelocytic leukemia protein PML interacts with the proline-rich homeodomain protein PRH: a RING may link hematopoiesis and growth control. Oncogene. 1999 Nov 25;18(50):7091–7100. doi: 10.1038/sj.onc.1203201. [DOI] [PubMed] [Google Scholar]
- Topisirovic Ivan, Culjkovic Biljana, Cohen Natalie, Perez Jacqueline M., Skrabanek Lucy, Borden Katherine L. B. The proline-rich homeodomain protein, PRH, is a tissue-specific inhibitor of eIF4E-dependent cyclin D1 mRNA transport and growth. EMBO J. 2003 Feb 3;22(3):689–703. doi: 10.1093/emboj/cdg069. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Touitou R., Richardson J., Bose S., Nakanishi M., Rivett J., Allday M. J. A degradation signal located in the C-terminus of p21WAF1/CIP1 is a binding site for the C8 alpha-subunit of the 20S proteasome. EMBO J. 2001 May 15;20(10):2367–2375. doi: 10.1093/emboj/20.10.2367. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhong S., Salomoni P., Pandolfi P. P. The transcriptional role of PML and the nuclear body. Nat Cell Biol. 2000 May;2(5):E85–E90. doi: 10.1038/35010583. [DOI] [PubMed] [Google Scholar]