Previous Article | Next Article 
Journal of Virology, September 2000, p. 8277-8285, Vol. 74, No. 18
0022-538X/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
In Vivo Genomic Footprinting of the Human T-Cell Leukemia Virus
Type 1 (HTLV-1) Long Terminal Repeat Enhancer Sequences in
HTLV-1-Infected Human T-Cell Lines with Different Levels of Tax
I Activity
Shoibal
Datta,
Nayantara H.
Kothari, and
Hung
Fan*
Cancer Research Institute and Department of
Molecular Biology and Biochemistry, University of California,
Irvine, California 92697
Received 19 April 2000/Accepted 16 June 2000
The Tax protein of human T-cell leukemia virus type 1 (HTLV-1)
enhances viral gene expression through sequences in the U3 region of
the viral long terminal repeat. These sequences consist of three
imperfect 21-bp repeats (TRE-1s) and a region between the
promoter-central and promoter-proximal 21-bp repeats (TRE-2). The
TRE-1s contain a core cyclic AMP response element (CRE) motif and can
be bound by CREB, ATF-1, ATF-2, and other members of the CREB-ATF
superfamily of transcription factors. Tax enhances CREB binding
to TRE-1 in vitro, and it promotes dimerization of CREB as well as
other bZIP proteins. Using ligation-mediated PCR on in vivo
dimethyl sulfate-treated HTLV-1-infected cell lines MT-2 and MT-4, we
have compiled a profile of protein occupancy in the HTLV-1 enhancer
sequences in the presence of high (MT-2) and low (MT-4) levels of
biologically active Tax I. The in vivo footprinting showed that all
three TRE-1s were bound by protein(s), but only in MT-2 cells. In MT-2
cells, all TRE-1s showed strong protection of the G residues in the
central CRE, and the footprints extended to differing degrees into the
GC-rich flanking sequences. This indicated Tax I-dependent
loading of transcription factors onto the HTLV-1 TRE-1s in vivo. In
vivo footprinting on TRE-2 indicated that this region was
bound by proteins regardless of the Tax I status of the cell line.
However, the presence of Tax I increased the extent and altered the
profile of proteins binding TRE-2 in vivo.
*
Corresponding author. Mailing address: Cancer Research
Institute, Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697. Phone: (949) 824-5554. Fax: (949) 824-4023. E-mail: hyfan{at}uci.edu.
Journal of Virology, September 2000, p. 8277-8285, Vol. 74, No. 18
0022-538X/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Landry, S., Halin, M., Vargas, A., Lemasson, I., Mesnard, J.-M., Barbeau, B.
(2009). Upregulation of Human T-Cell Leukemia Virus Type 1 Antisense Transcription by the Viral Tax Protein. J. Virol.
83: 2048-2054
[Abstract]
[Full Text]
-
Yoshida, M., Satou, Y., Yasunaga, J.-i., Fujisawa, J.-i., Matsuoka, M.
(2008). Transcriptional Control of Spliced and Unspliced Human T-Cell Leukemia Virus Type 1 bZIP Factor (HBZ) Gene. J. Virol.
82: 9359-9368
[Abstract]
[Full Text]
-
Miyazato, P., Yasunaga, J.-i., Taniguchi, Y., Koyanagi, Y., Mitsuya, H., Matsuoka, M.
(2006). De Novo Human T-Cell Leukemia Virus Type 1 Infection of Human Lymphocytes in NOD-SCID, Common {gamma}-Chain Knockout Mice. J. Virol.
80: 10683-10691
[Abstract]
[Full Text]
-
Grant, C., Jain, P., Nonnemacher, M., Flaig, K. E., Irish, B., Ahuja, J., Alexaki, A., Alefantis, T., Wigdahl, B.
(2006). AP-1-directed human T cell leukemia virus type 1 viral gene expression during monocytic differentiation. J. Leukoc. Biol.
80: 640-650
[Abstract]
[Full Text]
-
Zhang, L., Liu, M., Merling, R., Giam, C.-Z.
(2006). Versatile Reporter Systems Show that Transactivation by Human T-Cell Leukemia Virus Type 1 Tax Occurs Independently of Chromatin Remodeling Factor BRG1.. J. Virol.
80: 7459-7468
[Abstract]
[Full Text]
-
Xie, L., Green, P. L.
(2005). Envelope Is a Major Viral Determinant of the Distinct In Vitro Cellular Transformation Tropism of Human T-Cell Leukemia Virus Type 1 (HTLV-1) and HTLV-2. J. Virol.
79: 14536-14545
[Abstract]
[Full Text]
-
Koga, H., Ohshima, T., Shimotohno, K.
(2004). Enhanced Activation of Tax-dependent Transcription of Human T-cell Leukemia Virus Type I (HTLV-I) Long Terminal Repeat by TORC3. J. Biol. Chem.
279: 52978-52983
[Abstract]
[Full Text]
-
Lu, H., Pise-Masison, C. A., Linton, R., Park, H. U., Schiltz, R. L., Sartorelli, V., Brady, J. N.
(2004). Tax Relieves Transcriptional Repression by Promoting Histone Deacetylase 1 Release from the Human T-Cell Leukemia Virus Type 1 Long Terminal Repeat. J. Virol.
78: 6735-6743
[Abstract]
[Full Text]
-
Lemasson, I., Polakowski, N. J., Laybourn, P. J., Nyborg, J. K.
(2002). Transcription Factor Binding and Histone Modifications on the Integrated Proviral Promoter in Human T-cell Leukemia Virus-I-infected T-cells. J. Biol. Chem.
277: 49459-49465
[Abstract]
[Full Text]
-
Koiwa, T., Hamano-Usami, A., Ishida, T., Okayama, A., Yamaguchi, K., Kamihira, S., Watanabe, T.
(2002). 5'-Long Terminal Repeat-Selective CpG Methylation of Latent Human T-Cell Leukemia Virus Type 1 Provirus In Vitro and In Vivo. J. Virol.
76: 9389-9397
[Abstract]
[Full Text]
-
Liang, M.-H., Geisbert, T., Yao, Y., Hinrichs, S. H., Giam, C.-Z.
(2002). Human T-Lymphotropic Virus Type 1 Oncoprotein Tax Promotes S-Phase Entry but Blocks Mitosis. J. Virol.
76: 4022-4033
[Abstract]
[Full Text]