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Yamada A, Yasunaga J, Liang L, Zhang W, Sunagawa J, Nakaoka S, Iwami S, Kogure Y, Ito Y, Kataoka K, Nakagawa M, Iwanaga M, Utsunomiya A, Koh K, Watanabe T, Nosaka K, Matsuoka M. Anti-HTLV-1 immunity combined with proviral load as predictive biomarkers for adult T-cell leukemia-lymphoma. Cancer Sci 2024; 115:310-320. [PMID: 37950425 PMCID: PMC10823268 DOI: 10.1111/cas.15997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/23/2023] [Accepted: 10/03/2023] [Indexed: 11/12/2023] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) establishes chronic infection in humans and induces a T-cell malignancy called adult T-cell leukemia-lymphoma (ATL) and several inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Persistent HTLV-1 infection is established under the pressure of host immunity, and therefore the immune response against HTLV-1 is thought to reflect the status of the disease it causes. Indeed, it is known that cellular immunity against viral antigens is suppressed in ATL patients compared to HAM/TSP patients. In this study, we show that profiling the humoral immunity to several HTLV-1 antigens, such as Gag, Env, and Tax, and measuring proviral load are useful tools for classifying disease status and predicting disease development. Using targeted sequencing, we found that several carriers whom this profiling method predicted to be at high risk for developing ATL indeed harbored driver mutations of ATL. The clonality of HTLV-1-infected cells in those carriers was still polyclonal; it is consistent with an early stage of leukemogenesis. Furthermore, this study revealed significance of anti-Gag proteins to predict high risk group in HTLV-1 carriers. Consistent with this finding, anti-Gag cytotoxic T lymphocytes (CTLs) were increased in patients who received hematopoietic stem cell transplantation and achieved remission state, indicating the significance of anti-Gag CTLs for disease control. Our findings suggest that our strategy that combines anti-HTLV-1 antibodies and proviral load may be useful for prediction of the development of HTLV-1-associated diseases.
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Affiliation(s)
- Asami Yamada
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
| | - Jun‐ichirou Yasunaga
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
| | - Lihan Liang
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
| | - Wenyi Zhang
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
| | - Junya Sunagawa
- Graduate School of Life ScienceHokkaido UniversitySapporoJapan
| | - Shinji Nakaoka
- Faculty of Advanced Life ScienceHokkaido UniversitySapporoJapan
| | - Shingo Iwami
- Division of Natural Science, Graduate School of ScienceNagoya UniversityNagoyaJapan
| | - Yasunori Kogure
- Division of Molecular OncologyNational Cancer Center Research InstituteTokyoJapan
| | - Yuta Ito
- Division of Molecular OncologyNational Cancer Center Research InstituteTokyoJapan
- Division of Clinical Oncology and Hematology, Department of Internal MedicineThe Jikei University School of MedicineTokyoJapan
| | - Keisuke Kataoka
- Division of Molecular OncologyNational Cancer Center Research InstituteTokyoJapan
- Division of Hematology, Department of MedicineKeio University School of MedicineTokyoJapan
| | | | - Masako Iwanaga
- Department of Clinical EpidemiologyNagasaki University Graduate School of Biomedical SciencesNagasakiJapan
| | - Atae Utsunomiya
- Department of Hematology, Imamura General HospitalKagoshimaJapan
| | - Ki‐Ryang Koh
- Department of Hematology, Osaka General Hospital of West Japan Railway CompanyOsakaJapan
| | - Toshiki Watanabe
- Department of Practical Management of Medical Information, Graduate School of MedicineSt Marianna UniversityTokyoJapan
| | - Kisato Nosaka
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
| | - Masao Matsuoka
- Department of Hematology, Rheumatology, and Infectious Diseases, Graduate School of Medical Sciences, Faculty of Life SciencesKumamoto UniversityKumamotoJapan
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2
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Omsland M, Silic-Benussi M, Moles R, Sarkis S, Purcell DFJ, Yurick D, Khoury G, D'Agostino DM, Ciminale V, Franchini G. Functional properties and sequence variation of HTLV-1 p13. Retrovirology 2020; 17:11. [PMID: 32398094 PMCID: PMC7218495 DOI: 10.1186/s12977-020-00517-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/10/2020] [Indexed: 01/06/2023] Open
Abstract
Human T cell leukemia virus type-1 (HTLV-1) was the first retrovirus found to cause cancer in humans, but the mechanisms that drive the development of leukemia and other diseases associated with HTLV-1 infection remain to be fully understood. This review describes the functional properties of p13, an 87-amino acid protein coded by HTLV-1 open reading frame II (orf-II). p13 is mainly localized in the inner membrane of the mitochondria, where it induces potassium (K+) influx and reactive oxygen species (ROS) production, which can trigger either proliferation or apoptosis, depending on the ROS setpoint of the cell. Recent evidence indicates that p13 may influence the cell’s innate immune response to viral infection and the infected cell phenotype. Association of the HTLV-1 transcriptional activator, Tax, with p13 increases p13’s stability, leads to its partial co-localization with Tax in nuclear speckles, and reduces the ability of Tax to interact with the transcription cofactor CBP/p300. Comparison of p13 sequences isolated from HTLV-1-infected individuals revealed a small number of amino acid variations in the domains controlling the subcellular localization of the protein. Disruptive mutations of p13 were found in samples obtained from asymptomatic patients with low proviral load. p13 sequences of HTLV-1 subtype C isolates from indigenous Australian patients showed a high degree of identity among each other, with all samples containing a pattern of 5 amino acids that distinguished them from other subtypes. Further characterization of p13’s functional properties and sequence variants may lead to a deeper understanding of the impact of p13 as a contributor to the clinical manifestations of HTLV-1 infection.
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Affiliation(s)
- Maria Omsland
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | | | - Ramona Moles
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Sarkis Sarkis
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Damian F J Purcell
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, VIC, Australia
| | - David Yurick
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, VIC, Australia
| | - Georges Khoury
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, VIC, Australia.,Division of Microbiology and Immunology, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | | | - Vincenzo Ciminale
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy.,Department of Surgery, Oncology, and Gastroenterology, University of Padua, Padua, Italy
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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3
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D'Agostino DM, Cavallari I, Romanelli MG, Ciminale V. Post-transcriptional Regulation of HTLV Gene Expression: Rex to the Rescue. Front Microbiol 2019; 10:1958. [PMID: 31507567 PMCID: PMC6714889 DOI: 10.3389/fmicb.2019.01958] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 08/08/2019] [Indexed: 11/13/2022] Open
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) and other members of the Deltaretrovirus genus code for a regulatory protein named Rex that binds to the Rex-responsive element present on viral mRNAs. Rex rescues viral mRNAs from complete splicing or degradation and guides them to the cytoplasm for translation. The activity of Rex is essential for expression of viral transcripts coding for the virion components and thus represents a potential target for virus eradication. We present an overview of the functional properties of the HTLV-1 and HTLV-2 Rex proteins (Rex-1 and Rex-2), outline mechanisms controlling Rex function, and discuss similarities and differences in the sequences of Rex coded by HTLV-1, -2, -3, and -4 that may influence their molecular anatomy and functional properties.
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Affiliation(s)
| | | | - Maria Grazia Romanelli
- Section of Biology and Genetics, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Vincenzo Ciminale
- Istituto Oncologico Veneto IOV - IRCCS, Padua, Italy.,Department of Surgery, Oncology and Gastroenterology, University of Padova, Padua, Italy
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4
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Cavallari I, Scattolin G, Silic-Benussi M, Raimondi V, D'Agostino DM, Ciminale V. Mitochondrial Proteins Coded by Human Tumor Viruses. Front Microbiol 2018; 9:81. [PMID: 29467726 PMCID: PMC5808139 DOI: 10.3389/fmicb.2018.00081] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/12/2018] [Indexed: 12/26/2022] Open
Abstract
Viruses must exploit the cellular biosynthetic machinery and evade cellular defense systems to complete their life cycles. Due to their crucial roles in cellular bioenergetics, apoptosis, innate immunity and redox balance, mitochondria are important functional targets of many viruses, including tumor viruses. The present review describes the interactions between mitochondria and proteins coded by the human tumor viruses human T-cell leukemia virus type 1, Epstein-Barr virus, Kaposi's sarcoma-associated herpesvirus, human hepatitis viruses B and C, and human papillomavirus, and highlights how these interactions contribute to viral replication, persistence and transformation.
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Affiliation(s)
| | - Gloria Scattolin
- Department of Surgery, Oncology, and Gastroenterology, University of Padova, Padova, Italy
| | | | | | | | - Vincenzo Ciminale
- Veneto Institute of Oncology IOV-IRRCS, Padova, Italy.,Department of Surgery, Oncology, and Gastroenterology, University of Padova, Padova, Italy
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5
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Jayaraman D, Kenyon JC. New windows into retroviral RNA structures. Retrovirology 2018; 15:11. [PMID: 29368653 PMCID: PMC5784592 DOI: 10.1186/s12977-018-0393-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/12/2018] [Indexed: 12/16/2022] Open
Abstract
Background The multiple roles of both viral and cellular RNAs have become increasingly apparent in recent years, and techniques to model them have become significantly more powerful, enabling faster and more accurate visualization of RNA structures. Main body Techniques such as SHAPE (selective 2’OH acylation analysed by primer extension) have revolutionized the field, and have been used to examine RNAs belonging to many and diverse retroviruses. Secondary structure probing reagents such as these have been aided by the development of faster methods of analysis either via capillary or next-generation sequencing, allowing the analysis of entire genomes, and of retroviral RNA structures within virions. Techniques to model the three-dimensional structures of these large RNAs have also recently developed. Conclusions The flexibility of retroviral RNAs, both structural and functional, is clear from the results of these new experimental techniques. Retroviral RNA structures and structural changes control many stages of the lifecycle, and both the RNA structures themselves and their interactions with ligands are potential new drug targets. In addition, our growing understanding of retroviral RNA structures is aiding our knowledge of cellular RNA form and function.
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Affiliation(s)
- Dhivya Jayaraman
- Department of Medicine, National University of Singapore, 14 Medical Drive, MD 6, Level 15, Singapore, 117599, Singapore
| | - Julia Claire Kenyon
- Department of Medicine, University of Cambridge, Level 5 Addenbrookes Hospital Hills Rd, Cambridge, CB2 0QQ, UK. .,Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2 Blk MD4, Level 3, Singapore, 117545, Singapore. .,Homerton College, University of Cambridge, Hills Rd, Cambridge, CB2 8PH, UK.
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6
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Billman MR, Rueda D, Bangham CRM. Single-cell heterogeneity and cell-cycle-related viral gene bursts in the human leukaemia virus HTLV-1. Wellcome Open Res 2017. [DOI: 10.12688/wellcomeopenres.12469.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Background: The human leukaemia virus HTLV-1 expresses essential accessory genes that manipulate the expression, splicing and transport of viral mRNAs. Two of these genes,taxandhbz, also promote proliferation of the infected cell, and both genes are thought to contribute to oncogenesis in adult T-cell leukaemia/lymphoma. The regulation of HTLV-1 proviral latency is not understood. tax,on the proviral plus strand, is usually silent in freshly-isolated cells, whereas the minus-strand-encodedhbzgene is persistently expressed at a low level. However, the persistently activated host immune response to Tax indicates frequent expression oftaxin vivo. Methods: We used single-molecule RNA-FISH to quantify the expression of HTLV-1 transcripts at the single-cell level in a total of >19,000 cells from five T-cell clones, naturally infected with HTLV-1, isolated by limiting dilution from peripheral blood of HTLV-1-infected subjects. Results: We found strong heterogeneity both within and between clones in the expression of the proviral plus-strand (detected by hybridization to thetaxgene) and the minus-strand (hbzgene). Both genes are transcribed in bursts;taxexpression is enhanced in the absence ofhbz, whilehbzexpression increased in cells with hightaxexpression. Surprisingly, we found thathbzexpression is strongly associated with the S and G2/M phases of the cell cycle, independent oftaxexpression. Contrary to current belief,hbzis not expressed in all cells at all times, even within one clone. Inhbz-positive cells, the abundance ofhbztranscripts showed a very strong positive linear correlation with nuclear volume.Conclusions: The occurrence of intense, intermittent plus-strand gene bursts in independent primary HTLV-1-infected T-cell clones from unrelated individuals strongly suggests that the HTLV-1 plus-strand is expressed in bursts in vivo. Our results offer an explanation for the paradoxical correlations observed between the host immune response and HTLV-1 transcription.
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7
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Billman MR, Rueda D, Bangham CRM. Single-cell heterogeneity and cell-cycle-related viral gene bursts in the human leukaemia virus HTLV-1. Wellcome Open Res 2017; 2:87. [PMID: 29062917 PMCID: PMC5645716 DOI: 10.12688/wellcomeopenres.12469.2] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/17/2017] [Indexed: 12/26/2022] Open
Abstract
Background: The human leukaemia virus HTLV-1 expresses essential accessory genes that manipulate the expression, splicing and transport of viral mRNAs. Two of these genes,
tax and
hbz, also promote proliferation of the infected cell, and both genes are thought to contribute to oncogenesis in adult T-cell leukaemia/lymphoma. The regulation of HTLV-1 proviral latency is not understood.
tax, on the proviral plus strand, is usually silent in freshly-isolated cells, whereas the minus-strand-encoded
hbz gene is persistently expressed at a low level. However, the persistently activated host immune response to Tax indicates frequent expression of
taxin vivo. Methods: We used single-molecule RNA-FISH to quantify the expression of HTLV-1 transcripts at the single-cell level in a total of >19,000 cells from five T-cell clones, naturally infected with HTLV-1, isolated by limiting dilution from peripheral blood of HTLV-1-infected subjects. Results: We found strong heterogeneity both within and between clones in the expression of the proviral plus-strand (detected by hybridization to the
tax gene) and the minus-strand (
hbz gene). Both genes are transcribed in bursts;
tax expression is enhanced in the absence of
hbz, while
hbz expression increased in cells with high
tax expression. Surprisingly, we found that
hbz expression is strongly associated with the S and G
2/M phases of the cell cycle, independent of
tax expression. Contrary to current belief,
hbz is not expressed in all cells at all times, even within one clone. In
hbz-positive cells, the abundance of
hbz transcripts showed a very strong positive linear correlation with nuclear volume. Conclusions: The occurrence of intense, intermittent plus-strand gene bursts in independent primary HTLV-1-infected T-cell clones from unrelated individuals strongly suggests that the HTLV-1 plus-strand is expressed in bursts
in vivo. Our results offer an explanation for the paradoxical correlations observed between the host immune response and HTLV-1 transcription.
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Affiliation(s)
- Martin R Billman
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Imperial College London, Norfolk Place, London, UK
| | - David Rueda
- Single Molecule Imaging Group, MRC London Institute of Medical Sciences, Du Cane Road, London, UK.,Section of Virology, Division of Infectious Diseases, Department of Medicine, Imperial College London, Hammersmith Hospital, Du Cane Road, London , UK
| | - Charles R M Bangham
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Imperial College London, Norfolk Place, London, UK
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8
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RNA stability regulates human T cell leukemia virus type 1 gene expression in chronically-infected CD4 T cells. Virology 2017; 508:7-17. [PMID: 28478312 DOI: 10.1016/j.virol.2017.04.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 04/25/2017] [Accepted: 04/26/2017] [Indexed: 11/22/2022]
Abstract
Regulation of expression of HTLV-1 gene products from integrated proviruses plays an important role in HTLV-1-associated disease pathogenesis. Previous studies have shown that T cell receptor (TCR)- and phorbol ester (PMA) stimulation of chronically infected CD4 T cells increases the expression of integrated HTLV-1 proviruses in latently infected cells, however the mechanism remains unknown. Analysis of HTLV-1 RNA and protein species following PMA treatment of the latently HTLV-1-infected, FS and SP T cell lines demonstrated rapid induction of tax/rex mRNA. This rapid increase in tax/rex mRNA was associated with markedly enhanced tax/rex mRNA stability while the stability of unspliced or singly spliced HTLV-1 RNAs did not increase. Tax/rex mRNA in the HTLV-1 constitutively expressing cell lines exhibited high basal stability even without PMA treatment. Our data support a model whereby T cell activation leads to increased HTLV-1 gene expression at least in part through increased tax/rex mRNA stability.
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Miyazato P, Matsuo M, Katsuya H, Satou Y. Transcriptional and Epigenetic Regulatory Mechanisms Affecting HTLV-1 Provirus. Viruses 2016; 8:v8060171. [PMID: 27322309 PMCID: PMC4926191 DOI: 10.3390/v8060171] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/01/2016] [Accepted: 06/09/2016] [Indexed: 11/16/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus associated with human diseases, such as adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/Tropic spastic paraparesis (HAM/TSP). As a retrovirus, its life cycle includes a step where HTLV-1 is integrated into the host genomic DNA and forms proviral DNA. In the chronic phase of the infection, HTLV‑1 is known to proliferate as a provirus via the mitotic division of the infected host cells. There are generally tens of thousands of infected clones within an infected individual. They exist not only in peripheral blood, but also in various lymphoid organs. Viral proteins encoded in HTLV-1 genome play a role in the proliferation and survival of the infected cells. As is the case with other chronic viral infections, HTLV-1 gene expression induces the activation of the host immunity against the virus. Thus, the transcription from HTLV-1 provirus needs to be controlled in order to evade the host immune surveillance. There should be a dynamic and complex regulation in vivo, where an equilibrium between viral antigen expression and host immune surveillance is achieved. The mechanisms regulating viral gene expression from the provirus are a key to understanding the persistent/latent infection with HTLV-1 and its pathogenesis. In this article, we would like to review our current understanding on this topic.
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Affiliation(s)
- Paola Miyazato
- International Research Center for Medical Sciences, Center for AIDS Research, Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-0811, Japan.
| | - Misaki Matsuo
- International Research Center for Medical Sciences, Center for AIDS Research, Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-0811, Japan.
| | - Hiroo Katsuya
- International Research Center for Medical Sciences, Center for AIDS Research, Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-0811, Japan.
| | - Yorifumi Satou
- International Research Center for Medical Sciences, Center for AIDS Research, Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-0811, Japan.
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Nakano K, Watanabe T. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication. Viruses 2016; 8:58. [PMID: 26927155 PMCID: PMC4810248 DOI: 10.3390/v8030058] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 02/09/2016] [Accepted: 02/09/2016] [Indexed: 12/18/2022] Open
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function.
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Affiliation(s)
- Kazumi Nakano
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1, Shirokanedai, Minatoku, Tokyo 108-8639, Japan.
| | - Toshiki Watanabe
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1, Shirokanedai, Minatoku, Tokyo 108-8639, Japan.
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