共查询到20条相似文献,搜索用时 15 毫秒
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Human T-Cell Leukemia Virus Type 1 Tax Protein Abrogates Interleukin-2 Dependence in a Mouse T-Cell Line 总被引:2,自引:3,他引:2 下载免费PDF全文
Youichi Iwanaga Tomonori Tsukahara Takashi Ohashi Yuetsu Tanaka Masaaki Arai Masataka Nakamura Kiyoshi Ohtani Yoshihiro Koya Mari Kannagi Naoki Yamamoto Masahiro Fujii 《Journal of virology》1999,73(2):1271-1277
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Jianhua Fang Shigeki Kushida Renqing Feng Masakazu Tanaka Tomonori Kawamura Hideaki Abe Naoyoshi Maeda Makoto Onobori Mituo Hori Kazuhiko Uchida Masanao Miwa 《Journal of virology》1998,72(5):3952-3957
Human T-cell leukemia virus type 1 (HTLV-1) is associated with adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy/tropical spastic paraparesis, and other diseases. For prevention of the transmission of HTLV-1 and manifestation of these diseases, a small-animal model, especially a mouse model, would be useful. We injected HTLV-1-producing T cells (MT-2) intraperitoneally into neonatal C3H/HeJ mice. While the antibody against HTLV-1 antigens was not detectable in C3H/HeJ mice, HTLV-1 provirus was frequently detected in the spleen, lymph nodes, and thymus by PCR. HTLV-1 provirus was present at the level of 0 to 30 molecules in 105 spleen cells at the age of 15 weeks. In addition, a 59-bp flanking sequence of the HTLV-1 integration site was amplified from the spleen DNA by linker-mediated PCR and was confirmed to be derived from the mouse genome. HTLV-1 provirus was found in the T-cell fraction of the mouse spleen. These results indicate that mice can be infected by HTLV-1 and could serve as an animal model for the study of HTLV-1 infection and its pathogenesis in vivo. 相似文献
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Induction of Bcl-xL Expression by Human T-Cell Leukemia Virus Type 1 Tax through NF-κB in Apoptosis-Resistant T-Cell Transfectants with Tax 下载免费PDF全文
Tomonori Tsukahara Mari Kannagi Takashi Ohashi Hirotomo Kato Masaaki Arai Gabriel Nunez Youichi Iwanaga Naoki Yamamoto Kiyoshi Ohtani Masataka Nakamura Masahiro Fujii 《Journal of virology》1999,73(10):7981-7987
Human T-cell leukemia virus type 1 (HTLV-1) Tax is thought to play a pivotal role in immortalization of T cells. We have recently shown that the expression of Tax protected the mouse T-cell line CTLL-2 against apoptosis induced by interleukin-2 (IL-2) deprivation and converted its growth from being IL-2 dependent to being IL-2 independent. In this study, we demonstrate that constitutive expression of bcl-xl but not bcl-2, bcl-xs, bak, bad, or bax was associated with apoptosis resistance after IL-2 deprivation in CTLL-2 cells that expressed Tax. Transient-transfection assays showed that bcl-x promoter was transactivated by wild-type Tax. Similar effects were observed in mutant Tax retaining transactivating ability through NF-kappaB. Deletion or substitution of a putative NF-kappaB binding site identified in the bcl-x promoter significantly decreased Tax-induced transactivation. This NF-kappaB-like element was able to form a complex with NF-kappaB family proteins in vitro. Furthermore, Tax-induced transactivation of the bcl-x promoter was also diminished by the mutant IkappaBalpha, which specifically inhibits NF-kappaB activity. Our findings suggest that constitutive expression of Bcl-x(L) induced by Tax through the NF-kappaB pathway contributes to the inhibition of apoptosis in CTLL-2 cells after IL-2 deprivation. 相似文献
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Dustin Edwards Risaku Fukumoto Maria Fernanda de Castro-Amarante Luiz Carlos Junior Alcantara Bernardo Galv?o-Castro Robyn Washington Parks Cynthia Pise-Masison Genoveffa Franchini 《Journal of virology》2014,88(4):2319-2322
The orf-I gene of human T-cell leukemia type 1 (HTLV-1) encodes p8 and p12 and has a conserved cysteine at position 39. p8 and p12 form disulfide-linked dimers, and only the monomeric forms of p8 and p12 are palmitoylated. Mutation of cysteine 39 to alanine (C39A) abrogated dimerization and palmitoylation of both proteins. However, the ability of p8 to localize to the cell surface and to increase cell adhesion and viral transmission was not affected by the C39A mutation. 相似文献
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Efficient Expression and Rapid Purification of Human T-Cell Leukemia Virus Type 1 Protease 下载免费PDF全文
Y. Shirley Ding Sherry M. Owen Renu B. Lal Richard A. Ikeda 《Journal of virology》1998,72(4):3383-3386
Human T-cell leukemia virus type 1 (HTLV-1) is an oncovirus that is clinically associated with adult T-cell leukemia. We report here the construction of a pET19-based expression clone containing HTLV-1 protease fused to a decahistidine-containing leader peptide. The recombinant protein is efficiently expressed in Escherichia coli, and the fusion protein can be easily purified by affinity chromatography. Active mature protease in yields in excess of 3 mg/liter of culture can then be obtained by a novel two-step refolding and autoprocessing procedure. The purified enzyme exhibited Km and Kcat values of 0.3 mM and 0.143 sec−1 at pH 5.3 and was inhibited by pepstatin A. 相似文献
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Sheng Cao José O. Maldonado Iwen F. Grigsby Louis M. Mansky Wei Zhang 《Journal of virology》2015,89(4):2430-2435
The particle structure of human T-cell leukemia virus type 1 (HTLV-1) is poorly characterized. Here, we have used cryo-electron tomography to analyze HTLV-1 particle morphology. Particles produced from MT-2 cells were polymorphic, roughly spherical, and varied in size. Capsid cores, when present, were typically poorly defined polyhedral structures with at least one curved region contacting the inner face of the viral membrane. Most of the particles observed lacked a defined capsid core, which likely impacts HTLV-1 particle infectivity. 相似文献
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