Abstract
Human T-cell lymphotropic virus type I (HTLV-I) transactivator Tax augments transcription from three (cyclic AMP response element (CRE)-containing 21-bp repeats in the viral long terminal repeat and several other cis regulatory elements, including the NF-kappa B binding sites and the serum response element. Tax does not bind DNA directly; rather, it acts via cellular sequence-specific DNA binding proteins to stimulate transcription. We have shown recently that Tax forms multiprotein complexes with the heterodimeric and homodimeric forms of a ubiquitous cellular transcription factor, CREB (CRE binding protein). In vitro selection for preferred Tax-CREB binding sites indicates that the Tax-CREB complex exhibits greatly increased DNA recognition specificity and assembles preferentially on CRE motifs, TGACGT/C, flanked by long runs of G (5') and/or C (3') residues, as found in the HTLV-I 21-bp repeats. The indirect tethering of Tax to the 21-bp repeats via CREB is crucial for Tax transactivation. We now report the domain organization of Tax by characterizing its mutants. Tax mutants with alterations in the NH2 terminus, including three deletion mutants, Tax(6-353), Tax(21-353), and Tax(89-353), and two amino acid substitution mutants, M1 (H3S) and M7 (C29A, P30S), all failed to interact with CREB in vitro. In contrast, a short COOH-terminal deletion, Tax(1-319), and a Tax mutant with amino acid substitutions near the COOH end, M47 (L319R, L320S), were able to interact with CREB and the 21-bp repeats to assemble ternary Tax-CREB-DNA complexes. As demonstrated earlier, M1, M7, and M47 all failed to transactivate the HTLV-I long terminal repeat. Our data indicate that the defects in M1 and M7 result from an inability to interact with CREB. In contrast, the COOH-terminal mutations in M47 most likely inactivated the transactivation domain of Tax. As anticipated, a Tax mutant, M22 (G137A, L138S) which activated transcription from the 21-bp repeats with reduced capacity and was defective in trans activating the NF-kappa B binding sites, continued to interact with CREB in vitro, albeit with a lower level of efficiency. Finally, a glutathione S-transferase (GST)-Tax fusion protein with the GST moiety fused to the NH2 terminus of Tax failed to interact with CREB. Removal of the GST domain from GST-Tax by thrombin restores Tax's ability to assemble a ternary Tax-CREB-21-bp-repeat complex.(ABSTRACT TRUNCATED AT 400 WORDS)
Full Text
The Full Text of this article is available as a PDF (402.3 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adya N., Zhao L. J., Huang W., Boros I., Giam C. Z. Expansion of CREB's DNA recognition specificity by Tax results from interaction with Ala-Ala-Arg at positions 282-284 near the conserved DNA-binding domain of CREB. Proc Natl Acad Sci U S A. 1994 Jun 7;91(12):5642–5646. doi: 10.1073/pnas.91.12.5642. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bhagavati S., Ehrlich G., Kula R. W., Kwok S., Sninsky J., Udani V., Poiesz B. J. Detection of human T-cell lymphoma/leukemia virus type I DNA and antigen in spinal fluid and blood of patients with chronic progressive myelopathy. N Engl J Med. 1988 May 5;318(18):1141–1147. doi: 10.1056/NEJM198805053181801. [DOI] [PubMed] [Google Scholar]
- Brady J., Jeang K. T., Duvall J., Khoury G. Identification of p40x-responsive regulatory sequences within the human T-cell leukemia virus type I long terminal repeat. J Virol. 1987 Jul;61(7):2175–2181. doi: 10.1128/jvi.61.7.2175-2181.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Béraud C., Sun S. C., Ganchi P., Ballard D. W., Greene W. C. Human T-cell leukemia virus type I Tax associates with and is negatively regulated by the NF-kappa B2 p100 gene product: implications for viral latency. Mol Cell Biol. 1994 Feb;14(2):1374–1382. doi: 10.1128/mcb.14.2.1374. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cann A. J., Rosenblatt J. D., Wachsman W., Chen I. S. In vitro mutagenesis of the human T-cell leukemia virus types I and II tax genes. J Virol. 1989 Mar;63(3):1474–1479. doi: 10.1128/jvi.63.3.1474-1479.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Caron C., Rousset R., Béraud C., Moncollin V., Egly J. M., Jalinot P. Functional and biochemical interaction of the HTLV-I Tax1 transactivator with TBP. EMBO J. 1993 Nov;12(11):4269–4278. doi: 10.1002/j.1460-2075.1993.tb06111.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chen I. S., Slamon D. J., Rosenblatt J. D., Shah N. P., Quan S. G., Wachsman W. The x gene is essential for HTLV replication. Science. 1985 Jul 5;229(4708):54–58. doi: 10.1126/science.2990037. [DOI] [PubMed] [Google Scholar]
- Crenon I., Béraud C., Simard P., Montagne J., Veschambre P., Jalinot P. The transcriptionally active factors mediating the effect of the HTLV-I Tax transactivator on the IL-2R alpha kappa B enhancer include the product of the c-rel proto-oncogene. Oncogene. 1993 Apr;8(4):867–875. [PubMed] [Google Scholar]
- Felber B. K., Paskalis H., Kleinman-Ewing C., Wong-Staal F., Pavlakis G. N. The pX protein of HTLV-I is a transcriptional activator of its long terminal repeats. Science. 1985 Aug 16;229(4714):675–679. doi: 10.1126/science.2992082. [DOI] [PubMed] [Google Scholar]
- Fujii M., Sassone-Corsi P., Verma I. M. c-fos promoter trans-activation by the tax1 protein of human T-cell leukemia virus type I. Proc Natl Acad Sci U S A. 1988 Nov;85(22):8526–8530. doi: 10.1073/pnas.85.22.8526. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fujii M., Tsuchiya H., Chuhjo T., Akizawa T., Seiki M. Interaction of HTLV-1 Tax1 with p67SRF causes the aberrant induction of cellular immediate early genes through CArG boxes. Genes Dev. 1992 Nov;6(11):2066–2076. doi: 10.1101/gad.6.11.2066. [DOI] [PubMed] [Google Scholar]
- Fujii M., Tsuchiya H., Seiki M. HTLV-1 Tax has distinct but overlapping domains for transcriptional activation and for enhancer specificity. Oncogene. 1991 Dec;6(12):2349–2352. [PubMed] [Google Scholar]
- Fujisawa J., Toita M., Yoshida M. A unique enhancer element for the trans activator (p40tax) of human T-cell leukemia virus type I that is distinct from cyclic AMP- and 12-O-tetradecanoylphorbol-13-acetate-responsive elements. J Virol. 1989 Aug;63(8):3234–3239. doi: 10.1128/jvi.63.8.3234-3239.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Furuta Y., Aizawa S., Suda Y., Ikawa Y., Kishimoto H., Asano Y., Tada T., Hikikoshi A., Yoshida M., Seiki M. Thymic atrophy characteristic in transgenic mice that harbor pX genes of human T-cell leukemia virus type I. J Virol. 1989 Jul;63(7):3185–3189. doi: 10.1128/jvi.63.7.3185-3189.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gessain A., Barin F., Vernant J. C., Gout O., Maurs L., Calender A., de Thé G. Antibodies to human T-lymphotropic virus type-I in patients with tropical spastic paraparesis. Lancet. 1985 Aug 24;2(8452):407–410. doi: 10.1016/s0140-6736(85)92734-5. [DOI] [PubMed] [Google Scholar]
- Giam C. Z., Nerenberg M., Khoury G., Jay G. Expression of the complete human T-cell leukemia virus type I pX coding sequence as a functional protein in Escherichia coli. Proc Natl Acad Sci U S A. 1986 Oct;83(19):7192–7196. doi: 10.1073/pnas.83.19.7192. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Giam C. Z., Xu Y. L. HTLV-I tax gene product activates transcription via pre-existing cellular factors and cAMP responsive element. J Biol Chem. 1989 Sep 15;264(26):15236–15241. [PubMed] [Google Scholar]
- Gitlin S. D., Lindholm P. F., Marriott S. J., Brady J. N. Transdominant human T-cell lymphotropic virus type I TAX1 mutant that fails to localize to the nucleus. J Virol. 1991 May;65(5):2612–2621. doi: 10.1128/jvi.65.5.2612-2621.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hinrichs S. H., Nerenberg M., Reynolds R. K., Khoury G., Jay G. A transgenic mouse model for human neurofibromatosis. Science. 1987 Sep 11;237(4820):1340–1343. doi: 10.1126/science.2888191. [DOI] [PubMed] [Google Scholar]
- Hinuma Y., Komoda H., Chosa T., Kondo T., Kohakura M., Takenaka T., Kikuchi M., Ichimaru M., Yunoki K., Sato I. Antibodies to adult T-cell leukemia-virus-associated antigen (ATLA) in sera from patients with ATL and controls in Japan: a nation-wide sero-epidemiologic study. Int J Cancer. 1982 Jun 15;29(6):631–635. doi: 10.1002/ijc.2910290606. [DOI] [PubMed] [Google Scholar]
- Hirai H., Fujisawa J., Suzuki T., Ueda K., Muramatsu M., Tsuboi A., Arai N., Yoshida M. Transcriptional activator Tax of HTLV-1 binds to the NF-kappa B precursor p105. Oncogene. 1992 Sep;7(9):1737–1742. [PubMed] [Google Scholar]
- Inoue J., Yoshida M., Seiki M. Transcriptional (p40x) and post-transcriptional (p27x-III) regulators are required for the expression and replication of human T-cell leukemia virus type I genes. Proc Natl Acad Sci U S A. 1987 Jun;84(11):3653–3657. doi: 10.1073/pnas.84.11.3653. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jacobson S., Raine C. S., Mingioli E. S., McFarlin D. E. Isolation of an HTLV-1-like retrovirus from patients with tropical spastic paraparesis. Nature. 1988 Feb 11;331(6156):540–543. doi: 10.1038/331540a0. [DOI] [PubMed] [Google Scholar]
- Lanoix J., Lacoste J., Pepin N., Rice N., Hiscott J. Overproduction of NFKB2 (lyt-10) and c-Rel: a mechanism for HTLV-I Tax-mediated trans-activation via the NF-kappa B signalling pathway. Oncogene. 1994 Mar;9(3):841–852. [PubMed] [Google Scholar]
- Miyatake S., Seiki M., Yoshida M., Arai K. T-cell activation signals and human T-cell leukemia virus type I-encoded p40x protein activate the mouse granulocyte-macrophage colony-stimulating factor gene through a common DNA element. Mol Cell Biol. 1988 Dec;8(12):5581–5587. doi: 10.1128/mcb.8.12.5581. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Montagne J., Béraud C., Crenon I., Lombard-Platet G., Gazzolo L., Sergeant A., Jalinot P. Tax1 induction of the HTLV-I 21 bp enhancer requires cooperation between two cellular DNA-binding proteins. EMBO J. 1990 Mar;9(3):957–964. doi: 10.1002/j.1460-2075.1990.tb08194.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nerenberg M., Hinrichs S. H., Reynolds R. K., Khoury G., Jay G. The tat gene of human T-lymphotropic virus type 1 induces mesenchymal tumors in transgenic mice. Science. 1987 Sep 11;237(4820):1324–1329. doi: 10.1126/science.2888190. [DOI] [PubMed] [Google Scholar]
- Nyborg J. K., Dynan W. S., Chen I. S., Wachsman W. Binding of host-cell factors to DNA sequences in the long terminal repeat of human T-cell leukemia virus type I: implications for viral gene expression. Proc Natl Acad Sci U S A. 1988 Mar;85(5):1457–1461. doi: 10.1073/pnas.85.5.1457. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Osame M., Matsumoto M., Usuku K., Izumo S., Ijichi N., Amitani H., Tara M., Igata A. Chronic progressive myelopathy associated with elevated antibodies to human T-lymphotropic virus type I and adult T-cell leukemialike cells. Ann Neurol. 1987 Feb;21(2):117–122. doi: 10.1002/ana.410210203. [DOI] [PubMed] [Google Scholar]
- Paca-Uccaralertkun S., Zhao L. J., Adya N., Cross J. V., Cullen B. R., Boros I. M., Giam C. Z. In vitro selection of DNA elements highly responsive to the human T-cell lymphotropic virus type I transcriptional activator, Tax. Mol Cell Biol. 1994 Jan;14(1):456–462. doi: 10.1128/mcb.14.1.456. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Poiesz B. J., Ruscetti F. W., Gazdar A. F., Bunn P. A., Minna J. D., Gallo R. C. Detection and isolation of type C retrovirus particles from fresh and cultured lymphocytes of a patient with cutaneous T-cell lymphoma. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7415–7419. doi: 10.1073/pnas.77.12.7415. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pozzatti R., Vogel J., Jay G. The human T-lymphotropic virus type I tax gene can cooperate with the ras oncogene to induce neoplastic transformation of cells. Mol Cell Biol. 1990 Jan;10(1):413–417. doi: 10.1128/mcb.10.1.413. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rosen C. A., Sodroski J. G., Haseltine W. A. Location of cis-acting regulatory sequences in the human T-cell leukemia virus type I long terminal repeat. Proc Natl Acad Sci U S A. 1985 Oct;82(19):6502–6506. doi: 10.1073/pnas.82.19.6502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Semmes O. J., Jeang K. T. Definition of a minimal activation domain in human T-cell leukemia virus type I Tax. J Virol. 1995 Mar;69(3):1827–1833. doi: 10.1128/jvi.69.3.1827-1833.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Semmes O. J., Jeang K. T. Mutational analysis of human T-cell leukemia virus type I Tax: regions necessary for function determined with 47 mutant proteins. J Virol. 1992 Dec;66(12):7183–7192. doi: 10.1128/jvi.66.12.7183-7192.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith M. R., Greene W. C. Characterization of a novel nuclear localization signal in the HTLV-I tax transactivator protein. Virology. 1992 Mar;187(1):316–320. doi: 10.1016/0042-6822(92)90320-o. [DOI] [PubMed] [Google Scholar]
- Smith M. R., Greene W. C. Identification of HTLV-I tax trans-activator mutants exhibiting novel transcriptional phenotypes. Genes Dev. 1990 Nov;4(11):1875–1885. doi: 10.1101/gad.4.11.1875. [DOI] [PubMed] [Google Scholar]
- Smith M. R., Greene W. C. Type I human T cell leukemia virus tax protein transforms rat fibroblasts through the cyclic adenosine monophosphate response element binding protein/activating transcription factor pathway. J Clin Invest. 1991 Sep;88(3):1038–1042. doi: 10.1172/JCI115364. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sodroski J. G., Rosen C. A., Haseltine W. A. Trans-acting transcriptional activation of the long terminal repeat of human T lymphotropic viruses in infected cells. Science. 1984 Jul 27;225(4660):381–385. doi: 10.1126/science.6330891. [DOI] [PubMed] [Google Scholar]
- Tanaka A., Takahashi C., Yamaoka S., Nosaka T., Maki M., Hatanaka M. Oncogenic transformation by the tax gene of human T-cell leukemia virus type I in vitro. Proc Natl Acad Sci U S A. 1990 Feb;87(3):1071–1075. doi: 10.1073/pnas.87.3.1071. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Xu Y. L., Adya N., Siores E., Gao Q. S., Giam C. Z. Cellular factors involved in transcription and Tax-mediated trans-activation directed by the TGACGT motifs in human T-cell leukemia virus type I promoter. J Biol Chem. 1990 Nov 25;265(33):20285–20292. [PubMed] [Google Scholar]
- Zhao L. J., Giam C. Z. Human T-cell lymphotropic virus type I (HTLV-I) transcriptional activator, Tax, enhances CREB binding to HTLV-I 21-base-pair repeats by protein-protein interaction. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):7070–7074. doi: 10.1073/pnas.89.15.7070. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhao L. J., Giam C. Z. Interaction of the human T-cell lymphotrophic virus type I (HTLV-I) transcriptional activator Tax with cellular factors that bind specifically to the 21-base-pair repeats in the HTLV-I enhancer. Proc Natl Acad Sci U S A. 1991 Dec 15;88(24):11445–11449. doi: 10.1073/pnas.88.24.11445. [DOI] [PMC free article] [PubMed] [Google Scholar]