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Dodge MJ, MacNeil KM, Tessier TM, Weinberg JB, Mymryk JS. Emerging antiviral therapeutics for human adenovirus infection: Recent developments and novel strategies. Antiviral Res 2021; 188:105034. [PMID: 33577808 DOI: 10.1016/j.antiviral.2021.105034] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/04/2021] [Accepted: 02/05/2021] [Indexed: 12/11/2022]
Abstract
Human adenoviruses (HAdV) are ubiquitous human pathogens that cause a significant burden of respiratory, ocular, and gastrointestinal illnesses. Although HAdV infections are generally self-limiting, pediatric and immunocompromised individuals are at particular risk for developing severe disease. Currently, no approved antiviral therapies specific to HAdV exist. Recent outbreaks underscore the need for effective antiviral agents to treat life-threatening infections. In this review we will focus on recent developments in search of potential therapeutic agents for controlling HAdV infections, with a focus on those targeting post-entry stages of the virus replicative cycle.
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Affiliation(s)
- Mackenzie J Dodge
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Katelyn M MacNeil
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Tanner M Tessier
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada
| | - Jason B Weinberg
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA; Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA
| | - Joe S Mymryk
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada; Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada; Department of Oncology, The University of Western Ontario, London, ON, Canada; London Regional Cancer Program, Lawson Health Research Institute, London, ON, Canada.
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2
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Georgi F, Andriasyan V, Witte R, Murer L, Hemmi S, Yu L, Grove M, Meili N, Kuttler F, Yakimovich A, Turcatti G, Greber UF. The FDA-Approved Drug Nelfinavir Inhibits Lytic Cell-Free but Not Cell-Associated Nonlytic Transmission of Human Adenovirus. Antimicrob Agents Chemother 2020; 64:e01002-20. [PMID: 32601166 PMCID: PMC7449217 DOI: 10.1128/aac.01002-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 06/19/2020] [Indexed: 02/07/2023] Open
Abstract
Adenoviruses (AdVs) are prevalent and give rise to chronic and recurrent disease. Human AdV (HAdV) species B and C, such as HAdV-C2, -C5, and -B14, cause respiratory disease and constitute a health threat for immunocompromised individuals. HAdV-Cs are well known for lysing cells owing to the E3 CR1-β-encoded adenovirus death protein (ADP). We previously reported a high-throughput image-based screening framework and identified an inhibitor of HAdV-C2 multiround infection, nelfinavir mesylate. Nelfinavir is the active ingredient of Viracept, an FDA-approved inhibitor of human immunodeficiency virus (HIV) aspartyl protease that is used to treat AIDS. It is not effective against single-round HAdV infections. Here, we show that nelfinavir inhibits lytic cell-free transmission of HAdV, indicated by the suppression of comet-shaped infection foci in cell culture. Comet-shaped foci occur upon convection-based transmission of cell-free viral particles from an infected cell to neighboring uninfected cells. HAdV lacking ADP was insensitive to nelfinavir but gave rise to comet-shaped foci, indicating that ADP enhances but is not required for cell lysis. This was supported by the notion that HAdV-B14 and -B14p1 lacking ADP were highly sensitive to nelfinavir, although HAdV-A31, -B3, -B7, -B11, -B16, -B21, -D8, -D30, and -D37 were less sensitive. Conspicuously, nelfinavir uncovered slow-growing round HAdV-C2 foci, independent of neutralizing antibodies in the medium, indicative of nonlytic cell-to-cell transmission. Our study demonstrates the repurposing potential of nelfinavir with postexposure efficacy against different HAdVs and describes an alternative nonlytic cell-to-cell transmission mode of HAdV.
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Affiliation(s)
- Fanny Georgi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Vardan Andriasyan
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Robert Witte
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Luca Murer
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Silvio Hemmi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Lisa Yu
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Melanie Grove
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Nicole Meili
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Fabien Kuttler
- Biomolecular Screening Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Artur Yakimovich
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Artificial Intelligence for Life Sciences CIC, London, United Kingdom
| | - Gerardo Turcatti
- Biomolecular Screening Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
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3
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Georgi F, Greber UF. The Adenovirus Death Protein - a small membrane protein controls cell lysis and disease. FEBS Lett 2020; 594:1861-1878. [PMID: 32472693 DOI: 10.1002/1873-3468.13848] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/16/2022]
Abstract
Human adenoviruses (HAdVs) cause widespread acute and persistent infections. Infections are usually mild and controlled by humoral and cell-based immunity. Reactivation of persistently infected immune cells can lead to a life-threatening disease in immunocompromised individuals, especially children and transplant recipients. To date, no effective therapy or vaccine against HAdV disease is available to the public. HAdV-C2 and C5 are the best-studied of more than 100 HAdV types. They persist in infected cells and release their progeny by host cell lysis to neighbouring cells and fluids, a process facilitated by the adenovirus death protein (ADP). ADP consists of about 100 amino acids and harbours a single membrane-spanning domain. It undergoes post-translational processing in endoplasmic reticulum and Golgi compartments, before localizing to the inner nuclear membrane. Here, we discuss the current knowledge on how ADP induces membrane rupture. Membrane rupture is essential for both progression of disease and efficacy of therapeutic viruses in clinical applications, in particular oncolytic therapy.
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Affiliation(s)
- Fanny Georgi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
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4
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Donovan-Banfield I, Turnell AS, Hiscox JA, Leppard KN, Matthews DA. Deep splicing plasticity of the human adenovirus type 5 transcriptome drives virus evolution. Commun Biol 2020; 3:124. [PMID: 32170151 PMCID: PMC7070027 DOI: 10.1038/s42003-020-0849-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/12/2020] [Indexed: 02/06/2023] Open
Abstract
Viral genomes have high gene densities and complex transcription strategies rendering transcriptome analysis through short-read RNA-seq approaches problematic. Adenovirus transcription and splicing is especially complex. We used long-read direct RNA sequencing to study adenovirus transcription and splicing during infection. This revealed a previously unappreciated complexity of alternative splicing and potential for secondary initiating codon usage. Moreover, we find that most viral transcripts tend to shorten polyadenylation lengths as infection progresses. Development of an open reading frame centric bioinformatics analysis pipeline provided a deeper quantitative and qualitative understanding of adenovirus's genetic potential. Across the viral genome adenovirus makes multiple distinctly spliced transcripts that code for the same protein. Over 11,000 different splicing patterns were recorded across the viral genome, most occurring at low levels. This low-level use of alternative splicing patterns potentially enables the virus to maximise its coding potential over evolutionary timescales.
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Affiliation(s)
- I'ah Donovan-Banfield
- Department of Cellular and Molecular Medicine, School of Medical Sciences University Walk, University of Bristol, Bristol, BS8 1TD, UK
| | - Andrew S Turnell
- Institute of Cancer and Genomic Sciences College of Medical and Dental Sciences University of Birmingham Edgbaston, Birmingham, B15 2TT, UK
| | - Julian A Hiscox
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, ic2 Building, Liverpool, L3 5RF, UK
| | - Keith N Leppard
- Life Sciences University of Warwick Coventry, Coventry, CV4 7AL, UK
| | - David A Matthews
- Department of Cellular and Molecular Medicine, School of Medical Sciences University Walk, University of Bristol, Bristol, BS8 1TD, UK.
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5
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Pied N, Wodrich H. Imaging the adenovirus infection cycle. FEBS Lett 2019; 593:3419-3448. [PMID: 31758703 DOI: 10.1002/1873-3468.13690] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/18/2019] [Accepted: 11/20/2019] [Indexed: 12/11/2022]
Abstract
Incoming adenoviruses seize control of cytosolic transport mechanisms to relocate their genome from the cell periphery to specialized sites in the nucleoplasm. The nucleus is the site for viral gene expression, genome replication, and the production of progeny for the next round of infection. By taking control of the cell, adenoviruses also suppress cell-autonomous immunity responses. To succeed in their production cycle, adenoviruses rely on well-coordinated steps, facilitated by interactions between viral proteins and cellular factors. Interactions between virus and host can impose remarkable morphological changes in the infected cell. Imaging adenoviruses has tremendously influenced how we delineate individual steps in the viral life cycle, because it allowed the development of specific optical markers to label these morphological changes in space and time. As technology advances, innovative imaging techniques and novel tools for specimen labeling keep uncovering previously unseen facets of adenovirus biology emphasizing why imaging adenoviruses is as attractive today as it was in the past. This review will summarize past achievements and present developments in adenovirus imaging centered on fluorescence microscopy approaches.
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Affiliation(s)
- Noémie Pied
- CNRS UMR 5234, Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, France
| | - Harald Wodrich
- CNRS UMR 5234, Microbiologie Fondamentale et Pathogénicité, Université de Bordeaux, France
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6
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Jessup JM, Kabbout M, Korokhov N, Joun A, Tollefson AE, Wold WSM, Mattoo AR. Adenovirus and Oxaliplatin cooperate as agnostic sensitizers for immunogenic cell death in colorectal carcinoma. Hum Vaccin Immunother 2019; 16:636-644. [PMID: 31584324 PMCID: PMC7227684 DOI: 10.1080/21645515.2019.1665960] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Treatments with cytotoxic agents or viruses may cause Immunogenic Cell Death (ICD) that immunize tumor-bearing hosts but do not cause complete regression of tumor. We postulate that combining two ICD inducers may cause durable regression in immunocompetent mice. ICD was optimized in vitro by maximizing calreticulin externalization in human colorectal carcinoma (CRC) cells by exposure to mixtures of Oxaliplatin (OX) and human adenovirus (AdV). Six mm diameter CT26 or 4T1 carcinomas in flanks of BALB/c mice were injected once intratumorally (IT) with OX, AdV or their mixture. Tumor growth, Tumor-Infiltrating Lymphocytes (TIL), nodal cytotoxicity, and rejection of a viable cell challenge were measured. Tumors injected IT once with an optimum mixture of 80 µM OX - AdV 25 Multiplicity of Infection (MOI) in PBS buffer were 17-29% the volume of control tumors. When buffer was changed from PBS to 5% dextrose in water (D5W), volumes of tumors injected IT with 80 µM OX-AdV 25 MOI were 10% while IT OX or AdV alone were 32% and 40% the volume of IT buffer-treated tumors. OX-AdV IT increased CD3+ TIL by 4-fold, decreased CD8+ PD-1+ TIL from 79% to 19% and induced cytotoxicity to CT26 cells in draining node lymphocytes while lymphocytes from CT26-bearing untreated mice were not cytotoxic. OX-AdV IT in D5W caused complete regression in 40% of mice. Long-term survivors rejected a contralateral challenge of CT26. The buffer for Oxaliplatin is critical. The two ICD inducer mixture is promising as an agnostic sensitizer for carcinomas like colorectal carcinoma.
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Affiliation(s)
- J Milburn Jessup
- Inova Schar Cancer Institute, Falls Church, VA, USA.,School of Systems Biology, George Mason University, Fairfax, VA, USA
| | - Mohamed Kabbout
- Inova Schar Cancer Institute, Falls Church, VA, USA.,School of Systems Biology, George Mason University, Fairfax, VA, USA
| | | | - Alex Joun
- Inova Schar Cancer Institute, Falls Church, VA, USA.,School of Systems Biology, George Mason University, Fairfax, VA, USA
| | - Ann E Tollefson
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | - William S M Wold
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | - Abid R Mattoo
- Inova Schar Cancer Institute, Falls Church, VA, USA.,School of Systems Biology, George Mason University, Fairfax, VA, USA
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7
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Ismail AM, Lee JS, Lee JY, Singh G, Dyer DW, Seto D, Chodosh J, Rajaiya J. Adenoviromics: Mining the Human Adenovirus Species D Genome. Front Microbiol 2018; 9:2178. [PMID: 30254627 PMCID: PMC6141750 DOI: 10.3389/fmicb.2018.02178] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 08/24/2018] [Indexed: 12/19/2022] Open
Abstract
Human adenovirus (HAdV) infections cause disease world-wide. Whole genome sequencing has now distinguished 90 distinct genotypes in 7 species (A-G). Over half of these 90 HAdVs fall within species D, with essentially all of the HAdV-D whole genome sequences generated in the last decade. Herein, we describe recent new findings made possible by mining of this expanded genome database, and propose future directions to elucidate new functional elements and new functions for previously known viral components.
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Affiliation(s)
- Ashrafali M Ismail
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Ji Sun Lee
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Jeong Yoon Lee
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States.,Molecular Virology Laboratory, Korea Zoonosis Research Institute, Jeonbuk National University, Jeonju, South Korea
| | - Gurdeep Singh
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - David W Dyer
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Donald Seto
- Bioinformatics and Computational Biology Program, School of Systems Biology, George Mason University, Manassas, VI, United States
| | - James Chodosh
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Jaya Rajaiya
- Howe Laboratory, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, United States
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8
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The tripartite leader sequence is required for ectopic expression of HAdV-B and HAdV-E E3 CR1 genes. Virology 2017; 505:139-147. [PMID: 28259047 DOI: 10.1016/j.virol.2017.02.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 02/23/2017] [Indexed: 01/09/2023]
Abstract
The unique repertoire of genes that characterizes the early region 3 (E3) of the different species of human adenovirus (HAdV) likely contributes to their distinct pathogenic traits. The function of many E3 CR1 proteins remains unknown possibly due to unidentified intrinsic properties that make them difficult to express ectopically. This study shows that the species HAdV-B- and HAdV-E-specific E3 CR1 genes can be expressed from vectors carrying the HAdV tripartite leader (TPL) sequence but not from traditional mammalian expression vectors. Insertion of the TPL sequence upstream of the HAdV-B and HAdV-E E3 CR1 open reading frames was sufficient to rescue protein expression from pCI-neo constructs in transfected 293T cells. The detection of higher levels of HAdV-B and HAdV-E E3 CR1 transcripts suggests that the TPL sequence may enhance gene expression at both the transcriptional and translational levels. Our findings will facilitate the characterization of additional AdV E3 proteins.
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9
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Regulation of human adenovirus alternative RNA splicing by the adenoviral L4-33K and L4-22K proteins. Int J Mol Sci 2015; 16:2893-912. [PMID: 25636034 PMCID: PMC4346872 DOI: 10.3390/ijms16022893] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 01/06/2015] [Accepted: 01/22/2015] [Indexed: 01/12/2023] Open
Abstract
Adenovirus makes extensive use of alternative RNA splicing to produce a complex set of spliced viral mRNAs. Studies aimed at characterizing the interactions between the virus and the host cell RNA splicing machinery have identified three viral proteins of special significance for the control of late viral gene expression: L4-33K, L4-22K, and E4-ORF4. L4-33K is a viral alternative RNA splicing factor that controls L1 alternative splicing via an interaction with the cellular protein kinases Protein Kinase A (PKA) and DNA-dependent protein kinase (DNA-PK). L4-22K is a viral transcription factor that also has been implicated in the splicing of a subset of late viral mRNAs. E4-ORF4 is a viral protein that binds the cellular protein phosphatase IIA (PP2A) and controls Serine/Arginine (SR)-rich protein activity by inducing SR protein dephosphorylation. The L4-33K, and most likely also the L4-22K protein, are highly phosphorylated in vivo. Here we will review the function of these viral proteins in the post-transcriptional control of adenoviral gene expression and further discuss the significance of potential protein kinases phosphorylating the L4-33K and/or L4-22K proteins.
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10
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Gao Q, Chen C, Ji T, Wu P, Han Z, Fang H, Li F, Liu Y, Hu W, Gong D, Zhang Z, Wang S, Zhou J, Ma D. A systematic comparison of the anti-tumoural activity and toxicity of the three Adv-TKs. PLoS One 2014; 9:e94050. [PMID: 24722669 PMCID: PMC3983249 DOI: 10.1371/journal.pone.0094050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Accepted: 03/11/2014] [Indexed: 11/18/2022] Open
Abstract
Adenovirus 5 vectors, known respectively as, the first generation, second generation and oncolytic adenovirus, have been studied extensively in preclinical and clinical trials. However, hitherto few systemic evaluations of the efficacy and toxicity of these adenoviral vectors that have reflected the vertical history of adenovirus based cancer gene therapy strategies have been undertaken. This study has chosen Adv-TK, the well-established adjuvant treatment in cancer, and compared its efficacy and safety with those of the two newly synthesized oncolytic adenovirus vectors encoding the HSV-TK gene, namely M7 and M8. The results obtained showed that systemic administration of 1×108 pfu M7 had an anti-tumour efficacy similar to that of 3×1010 pfu Adv-TK whilst M8 performed even better. Furthermore, compared to Adv-TK, M7 and M8 reduced the incidence of metastases and substantially prolonged the survival time of the mice xenografted with human orthotopic gastric carcinomas with disseminated metastasis. Even more exciting, however, were the similar toxic and immune safety results obtained from the administration of high doses of M7 or M8 in comparison with Adv-TK in immunocompetent and permissive syrian hamster. The data here exhibit a comprehensive display of the efficacy and safety of the three mutants and provide evidence for the future preclinical use of the M7 and M8 viruses.
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Affiliation(s)
- Qinglei Gao
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Caihong Chen
- Center of Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Teng Ji
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Peng Wu
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Zhiqiang Han
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Haiyan Fang
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Fei Li
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Yi Liu
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Wencheng Hu
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Danni Gong
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | | | - Shixuan Wang
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
| | - Jianfeng Zhou
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
- * E-mail: (DM); (JZ)
| | - Ding Ma
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
- * E-mail: (DM); (JZ)
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11
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Bombyx mori bidensovirus: The type species of the new genus Bidensovirus in the new family Bidnaviridae. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s11434-013-5876-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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12
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Abstract
Genes within the E3 transcription unit of human adenoviruses modulate host immune responses to infection. A comprehensive genomics and bioinformatics analysis of the E3 transcription unit for 38 viruses within human adenovirus species D (HAdV-D) revealed distinct and surprising patterns of homologous recombination. Homologous recombination was identified in open reading frames for E3 CR1α, CR1β, and CR1γ, similar to that previously observed with genes encoding the three major structural capsid proteins, the penton base, hexon, and fiber.
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13
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Lu ZZ, Zou XH, Lastinger K, Williams A, Qu JG, Estes DM. Enhanced growth of recombinant human adenovirus type 41 (HAdV-41) carrying ADP gene. Virus Res 2013; 176:61-8. [PMID: 23769974 DOI: 10.1016/j.virusres.2013.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/09/2013] [Accepted: 05/10/2013] [Indexed: 12/11/2022]
Abstract
Human adenovirus type 41 (HAdV-41) has the potential to be constructed as a gene transfer vector for oral vaccine or gene therapy targeting gastrointestinal tract. Block in release of progeny virus from host cell severely affects the yield during virus amplification. In this study, HAdV-5 adenovirus death protein (ADP) gene was used to replace the open reading frames (ORFs) of the HAdV-41 E3 region to construct a backbone plasmid pAdbone41ADP. Recombinant adenoviral plasmids harboring ADP and GFP genes (pAd41ADP-GFP) were generated. Plaques were formed and HAdV-41-ADP-GFP virus was rescued after transfecting pAd41ADP-GFP into the packaging cell line 293TE32. When amplified on 293TE32 cells, HAdV-41-ADP-GFP virus released to the culture medium was 10-50 times more than control virus HAdV-41-GFP, which did not carry ADP gene. The results demonstrated that incorporation of the ADP gene substantially increased the yield of recombinant HAdV-41 virus through enhancing spread of progeny virus among packaging cells.
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Affiliation(s)
- Zhuo-Zhuang Lu
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, GA 30602, USA
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14
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Yakimovich A, Gumpert H, Burckhardt CJ, Lütschg VA, Jurgeit A, Sbalzarini IF, Greber UF. Cell-free transmission of human adenovirus by passive mass transfer in cell culture simulated in a computer model. J Virol 2012; 86:10123-37. [PMID: 22787215 PMCID: PMC3446567 DOI: 10.1128/jvi.01102-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 07/03/2012] [Indexed: 01/10/2023] Open
Abstract
Viruses spread between cells, tissues, and organisms by cell-free and cell-cell transmissions. Both mechanisms enhance disease development, but it is difficult to distinguish between them. Here, we analyzed the transmission mode of human adenovirus (HAdV) in monolayers of epithelial cells by wet laboratory experimentation and a computer simulation. Using live-cell fluorescence microscopy and replication-competent HAdV2 expressing green fluorescent protein, we found that the spread of infection invariably occurred after cell lysis. It was affected by convection and blocked by neutralizing antibodies but was independent of second-round infections. If cells were overlaid with agarose, convection was blocked and round plaques developed around lytic infected cells. Infected cells that did not lyse did not give rise to plaques, highlighting the importance of cell-free transmission. Key parameters for cell-free virus transmission were the time from infection to lysis, the dose of free viruses determining infection probability, and the diffusion of single HAdV particles in aqueous medium. With these parameters, we developed an in silico model using multiscale hybrid dynamics, cellular automata, and particle strength exchange. This so-called white box model is based on experimentally determined parameters and reproduces viral infection spreading as a function of the local concentration of free viruses. These analyses imply that the extent of lytic infections can be determined by either direct plaque assays or can be predicted by calculations of virus diffusion constants and modeling.
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Affiliation(s)
- Artur Yakimovich
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
| | - Heidi Gumpert
- MOSAIC Group, Institute of Theoretical Computer Science and Swiss Institute of Bioinformatics, ETH Zürich, Zürich, Switzerland
| | | | - Verena A. Lütschg
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
| | - Andreas Jurgeit
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
| | - Ivo F. Sbalzarini
- MOSAIC Group, Institute of Theoretical Computer Science and Swiss Institute of Bioinformatics, ETH Zürich, Zürich, Switzerland
| | - Urs F. Greber
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
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The adenovirus L4-22K protein is multifunctional and is an integral component of crucial aspects of infection. J Virol 2012; 86:10474-83. [PMID: 22811519 DOI: 10.1128/jvi.01463-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A variety of cellular and viral processes are coordinately regulated during adenovirus (Ad) infection to achieve optimal virus production. The Ad late gene product L4-22K has been associated with disparate activities during infection, including the regulation of late gene expression, viral DNA packaging, and infectious virus production. We generated and characterized two L4-22K mutant viruses to further explore L4-22K functions during viral infection. Our results show that L4-22K is indeed important for temporal control of viral gene expression not only because it activates late gene expression but also because it suppresses early gene expression. We also show that the L4-22K protein binds to viral packaging sequences in vivo and is essential to recruit two other packaging proteins, IVa2 and L1-52/55K, to this region. The elimination of L4-22K gave rise to the production of only empty virus capsids and not mature virions, which confirms that the L4-22K protein is required for Ad genome packaging. Finally, L4-22K contributes to adenovirus-induced cell death by regulating the expression of the adenovirus death protein. Thus, the adenovirus L4-22K protein is multifunctional and an integral component of crucial aspects of infection.
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Wang W, Xia X, Wang S, Sima N, Li Y, Han Z, Gao Q, Luo A, Li K, Meng L, Zhou J, Wang C, Shen K, Ma D. Oncolytic adenovirus armed with human papillomavirus E2 gene in combination with radiation demonstrates synergistic enhancements of antitumor efficacy. Cancer Gene Ther 2011; 18:825-36. [DOI: 10.1038/cgt.2011.53] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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17
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The non-structural protein NS-2 of Bombyx mori parvo-like virus is localized to the nuclear membrane. Curr Microbiol 2011; 63:8-15. [PMID: 21479931 DOI: 10.1007/s00284-011-9933-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Accepted: 03/30/2011] [Indexed: 01/13/2023]
Abstract
Bombyx mori parvo-like virus (BmPLV) has two complementary single-stranded DNA genome (VD1 and VD2) and owns a self-encoding DNA polymerase motif, but its replication mechanism is unclear. In our previous research, a protein encoded by VD1-ORF1 was indentified in the midgut of BmPLV China Zhenjiang isolate-(BmPLV-Z) infected silkworm larvae via two-dimensional gel electrophoresis (2-DE). This protein was named as non-structural protein 2 (NS2), which showed no similarity to that of parvoviruses. To date, little is known about it. In this study, sequence alignment results showed that NS2 shared homology with some chromosomal replication initiator protein dnaA and DNA-binding response regulators. The ns2 was cloned and expressed in E. coli, and then a polyclonal antibody of the NS2 protein was prepared successfully. The data from real-time quantitative PCR displayed that the transcription of VD1-ORF1 from BmPLV-Z-infected midguts started from 28-h post inoculation (h p.i.) in low amounts, but in high amounts at late stages of infection. Immunofluorescence showed that NS2 ultimately concentrated on the nuclear membrane in BmN cells at late stages, indicating that NS2 might be associated with integral membrane protein.
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van den Hengel SK, de Vrij J, Uil TG, Lamfers ML, Sillevis Smitt PA, Hoeben RC. Truncating the i-leader open reading frame enhances release of human adenovirus type 5 in glioma cells. Virol J 2011; 8:162. [PMID: 21477385 PMCID: PMC3090740 DOI: 10.1186/1743-422x-8-162] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 04/11/2011] [Indexed: 11/10/2022] Open
Abstract
Background The survival of glioma patients with the current treatments is poor. Early clinical trails with replicating adenoviruses demonstrated the feasibility and safety of the use of adenoviruses as oncolytic agents. Antitumor efficacy has been moderate due to inefficient virus replication and spread. Previous studies have shown that truncation of the adenovirus i-leader open reading frame enhanced cytopathic activity of HAdV-5 in several tumor cell lines. Here we report the effect of an i-leader mutation on the cytopathic activity in glioma cell lines and in primary high-grade glioma cell cultures. Results A mutation truncating the i-leader open reading frame was created in a molecular clone of replication-competent wild-type HAdV-5 by site-directed mutagenesis. We analyzed the cytopathic activity of this RL-07 mutant virus. A cell-viability assay showed increased cytopathic activity of the RL-07 mutant virus on U251 and SNB19 glioma cell lines. The plaque sizes of RL-07 on U251 monolayers were seven times larger than those of isogenic control viruses. Similarly, the cytopathic activity of the RL-07 viruses was strongly increased in six primary high-grade glioma cell cultures. In glioma cell lines the RL-07 virus was found to be released earlier into the culture medium. This was not due to enhanced viral protein synthesis, as was evident from equivalent E1A, Fiber and Adenovirus Death Protein amounts, nor to higher virus yields. Conclusion The cytopathic activity of replicating adenovirus in glioblastoma cells is increased by truncating the i-leader open reading frame. Such mutations may help enhancing the antitumor cytopathic efficacy of oncolytic adenoviruses in the treatment of glioblastoma.
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Affiliation(s)
- Sanne K van den Hengel
- Department of Molecular Cell Biology, Leiden University Medical Center, P.O. Box 9600, 2300 RC, Leiden, The Netherlands.
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19
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Uil TG, Vellinga J, de Vrij J, van den Hengel SK, Rabelink MJWE, Cramer SJ, Eekels JJM, Ariyurek Y, van Galen M, Hoeben RC. Directed adenovirus evolution using engineered mutator viral polymerases. Nucleic Acids Res 2010; 39:e30. [PMID: 21138963 PMCID: PMC3061072 DOI: 10.1093/nar/gkq1258] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Adenoviruses (Ads) are the most frequently used viruses for oncolytic and gene therapy purposes. Most Ad-based vectors have been generated through rational design. Although this led to significant vector improvements, it is often hampered by an insufficient understanding of Ad’s intricate functions and interactions. Here, to evade this issue, we adopted a novel, mutator Ad polymerase-based, ‘accelerated-evolution’ approach that can serve as general method to generate or optimize adenoviral vectors. First, we site specifically substituted Ad polymerase residues located in either the nucleotide binding pocket or the exonuclease domain. This yielded several polymerase mutants that, while fully supportive of viral replication, increased Ad’s intrinsic mutation rate. Mutator activities of these mutants were revealed by performing deep sequencing on pools of replicated viruses. The strongest identified mutators carried replacements of residues implicated in ssDNA binding at the exonuclease active site. Next, we exploited these mutators to generate the genetic diversity required for directed Ad evolution. Using this new forward genetics approach, we isolated viral mutants with improved cytolytic activity. These mutants revealed a common mutation in a splice acceptor site preceding the gene for the adenovirus death protein (ADP). Accordingly, the isolated viruses showed high and untimely expression of ADP, correlating with a severe deregulation of E3 transcript splicing.
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Affiliation(s)
- Taco G Uil
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, 2300 RC, The Netherlands
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20
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Identification of a previously unrecognized promoter that drives expression of the UXP transcription unit in the human adenovirus type 5 genome. J Virol 2010; 84:11470-8. [PMID: 20739525 DOI: 10.1128/jvi.01338-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously identified an adenovirus (Ad) protein named U exon protein (UXP) encoded by a leftward-strand (l-strand) transcription unit. Here we identify and characterize the UXP promoter. Primer extension and RNase protection assays mapped the transcription initiation site at 32 nucleotides upstream of the UXP gene initiation codon. A series of viral mutants with mutations at two putative inverted CCAAT (I-CCAAT) boxes and two E2F sites were generated. With mutants lacking the proximal I-CCAAT box, the UXP mRNA level decreased significantly to 30% of the Ad type 5 (Ad5) mRNA level as measured by quantitative reverse transcription-PCR. Decreased UXP was also observed by immunoblotting and immunofluorescence. UXP mRNA and protein levels were similar to those of Ad5 for mutants lacking the distal I-CCAAT box or both putative E2F sites. Ad DNA levels were similar in mutant- and wild-type Ad5-infected cells during the late stage of infection, strongly suggesting that the decreased UXP mRNA and protein from mutants lacking the proximal I-CCAAT box was due to decreased promoter activity. Electrophoretic mobility shift assays (EMSA) indicated that a cellular factor binds specifically to the proximal I-CCAAT box of the UXP promoter. An in vitro luciferase reporter assay demonstrated that basal promoter activity lies between bp -158 and +30 of the transcription initiation site. No E1A-mediated promoter transactivation was observed in 293 cells compared with A549 cells. Thus, we propose that there is a previously unidentified Ad5 promoter that drives expression of the UXP transcription unit. This promoter is embedded within the gene for fiber, and it contains a proximal I-CCAAT box critical for UXP mRNA transcription.
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21
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Open reading frame E3-10.9K of subspecies B1 human adenoviruses encodes a family of late orthologous proteins that vary in their predicted structural features and subcellular localization. J Virol 2010; 84:11310-22. [PMID: 20739542 DOI: 10.1128/jvi.00512-10] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Subspecies B1 human adenoviruses (HAdV-B1s) are important causative agents of acute respiratory disease, but the molecular bases of their distinct pathobiology are still poorly understood. Marked differences in genetic content between HAdV-B1s and the well-characterized HAdV-Cs that may contribute to distinct pathogenic properties map to the E3 region. Between the highly conserved E3-19K and E3-10.4K/RIDα open reading frames (ORFs), and in the same location as the HAdV-C ADP/E3-11.6K ORF, HAdV-B1s carry ORFs E3-20.1K and E3-20.5K and a polymorphic third ORF, designated E3-10.9K, that varies in the size of its predicted product among HAdV-B1 serotypes and genomic variants. As an initial effort to define the function of the E3-10.9K ORF, we carried out a biochemical characterization of E3-10.9K-encoded orthologous proteins and investigated their expression in infected cells. Sequence-based predictions suggested that E3-10.9K orthologs with a hydrophobic domain are integral membrane proteins. Ectopically expressed, C-terminally tagged (with enhanced green fluorescent protein [EGFP]) E3-10.9K and E3-9K localized primarily to the plasma membrane, while E3-7.7K localized primarily to a juxtanuclear compartment that could not be identified. EGFP fusion proteins with a hydrophobic domain were N and O glycosylated. EGFP-tagged E3-4.8K, which lacked the hydrophobic domain, displayed diffuse cellular localization similar to that of the EGFP control. E3-10.9K transcripts from the major late promoter were detected at late time points postinfection. A C-terminally hemagglutinin-tagged version of E3-9K was detected by immunoprecipitation at late times postinfection in the membrane fraction of mutant virus-infected cells. These data suggest a role for ORF E3-10.9K-encoded proteins at late stages of HAdV-B1 replication, with potentially important functional implications for the documented ORF polymorphism.
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Gros A, Martínez-Quintanilla J, Puig C, Guedan S, Molleví DG, Alemany R, Cascallo M. Bioselection of a gain of function mutation that enhances adenovirus 5 release and improves its antitumoral potency. Cancer Res 2008; 68:8928-37. [PMID: 18974137 DOI: 10.1158/0008-5472.can-08-1145] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Genetic bioselection of a mutagenized Ad5wt stock in human tumor xenografts led us to isolate AdT1, a mutant displaying a large-plaque phenotype in vitro and an enhanced systemic antitumor activity in vivo. AdT1 phenotype correlates with an increased progeny release without affecting total viral yield in different human tumors and cancer-associated fibroblasts. An approach combining hybrid Ad5/AdT1 recombinants and sequencing identified a truncating insertion in the endoplasmic reticulum retention domain of the E3/19K protein (445A mutation) which relocates the protein to the plasma membrane and is responsible for AdT1's enhanced release. E3/19K-445A phenotype does not correlate with the protein's ability to interact with MHC-I or induce apoptosis. Intracellular calcium measurement revealed that the 445A mutation induces extracellular Ca(2+) influx, deregulating intracellular Ca(2+) homeostasis and inducing membrane permeabilization, a viroporin-like function. E3/19K-445A mutants also display enhanced antitumoral activity when injected both intratumorally and systemically in different models in vivo. Our results indicate that the inclusion of mutation 445A in tumor-selective adenoviruses would be a very powerful tool to enhance their antitumor efficacy.
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Affiliation(s)
- Alena Gros
- Translational Research Laboratory, IDIBELL-Institut Català d'Oncologia, L'Hospitalet de Llobregat, Barcelona, Spain
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23
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Increased therapeutic efficacy of the prostate-specific oncolytic adenovirus Ad[I/PPT-E1A] by reduction of the insulator size and introduction of the full-length E3 region. Cancer Gene Ther 2008; 15:203-13. [PMID: 18188185 DOI: 10.1038/sj.cgt.7701117] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Conditionally replicating adenoviruses are developing as a complement to traditional cancer therapies. Ad[I/PPT-E1A] is an E1B/E3-deleted virus that replicates exclusively in prostate cells, since the expression of E1A is controlled by the recombinant 1.4 kb prostate-specific PPT promoter. The transcriptional integrity of PPT is maintained by the 3.0 kb mouse H19 insulator that was introduced directly upstream of the PPT sequence. In order to increase the cloning capacity to be able to reintroduce E3 sequences in the 35.7 kb Ad[I/PPT-E1A] genome, various shorter insulators were examined in a luciferase reporter gene assay. It was found that the 1.6 kb core H19 insulator (i) improves the activity of PPT, compared to the 3.0 kb full-length insulator, while still maintaining prostate cell specificity and releasing 1.4 kb of space for insertion of additional sequences. To improve the ability of the virus to efficiently lyse infected cells and persist in vivo, we inserted the adenovirus death protein (ADP) or the full-length adenovirus E3 region. The oncolytic activity of PPT-E1A-based viruses was studied using MTS, crystal violet and replication assays. The virus with the reintroduced full-length E3-region (Ad[i/PPT-E1A, E3]) showed the highest cytopathic effects in vitro. Furthermore, this virus suppressed the growth of aggressively growing prostate tumors in vivo. Therefore, we conclude that Ad[i/PPT-E1A, E3] is a prostate-specific oncolytic adenovirus with a high potential for treating localized prostate cancer.
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Shashkova EV, Spencer JF, Wold WSM, Doronin K. Targeting Interferon-α Increases Antitumor Efficacy and Reduces Hepatotoxicity of E1A-mutated Spread-enhanced Oncolytic Adenovirus. Mol Ther 2007; 15:598-607. [PMID: 17191072 DOI: 10.1038/sj.mt.6300064] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Accepted: 10/30/2006] [Indexed: 11/09/2022] Open
Abstract
Novel approaches are needed to improve the antitumor potency and to increase the cancer specificity of oncolytic adenoviruses (Ad). We hypothesized that the combination of interferon-alpha (IFN-alpha) expression with a specific mutation in the e1a gene of Ad could target vector replication to genetic defects in the IFN-alpha pathway resulting in both improved antitumor efficacy and reduced toxicity. The conditionally replicative Ad vector KD3-IFN carries the dl1101/1107 mutation in the e1a gene that eliminates binding of E1A proteins to p300/CBP and pRb. KD3-IFN expresses human IFN-alpha in concurrence with vector replication and overexpresses the adenovirus death protein (ADP; E3-11.6K). The antitumor activity of KD3-IFN was significantly higher than that of a control vector in established human hepatocellular carcinoma tumors in immunodeficient mice and in hamster kidney cancer tumors in immunocompetent Syrian hamsters. The dl1101/1107 mutation rendered Ad replication sensitive to the antiviral effect of IFN-alpha in normal as opposed to cancer cells. These results translated to reduced vector toxicity upon systemic administration to C57BL/6 mice. The combination of Ad oncolysis, ADP overexpression, and IFN-alpha-mediated immunotherapy represents a three-pronged approach for increasing the anticancer efficacy of replicative Ads. Exploiting the dl1101/1107 mutation provides a mechanism for additional selectivity of IFN-alpha-expressing replication-competent Ads.
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25
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Timpe JM, Verrill KC, Black BN, Ding HF, Trempe JP. Adeno-associated virus induces apoptosis during coinfection with adenovirus. Virology 2006; 358:391-401. [PMID: 17011012 PMCID: PMC1839828 DOI: 10.1016/j.virol.2006.08.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Revised: 08/11/2006] [Accepted: 08/23/2006] [Indexed: 12/20/2022]
Abstract
Adeno-associated virus (AAV) is a nonpathogenic parvovirus that efficiently replicates in the presence of adenovirus (Ad). Exogenous expression of the AAV replication proteins induces caspase-dependent apoptosis, but determining if AAV infection causes apoptosis during viral infection is complicated by Ad-mediated programmed cell death. To eliminate Ad-induced cytolysis, we used an E3 adenoviral death protein (ADP) mutant, pm534. AAV and pm534-coinfected cells exhibited increased cell killing compared to pm534 alone. Relative to cells infected with Ad alone, AAV and wild-type Ad-infected cells displayed decreased ADP expression, increased cytolysis until the third day of the infection, and decreased cytolysis thereafter. Biochemical and morphological characteristics of apoptosis were observed during coinfections with AAV and pm534 or Ad, including a moderate degree of caspase activation that was not present during infections with pm534 or Ad alone. AAV coinfection also increased extracellular pH. These studies suggest that AAV induces caspase-dependent and caspase-independent apoptosis.
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Affiliation(s)
- Jennifer M Timpe
- Department of Biochemistry and Cancer Biology, Medical University of Ohio, 3035 Arlington Ave., Toledo, OH 43614-5804, USA
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26
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Gao Q, Zhou J, Huang X, Chen G, Ye F, Lu Y, Li K, Zhuang L, Huang M, Xu G, Wang S, Ma D. RETRACTED: Selective targeting of checkpoint kinase 1 in tumor cells with a novel potent oncolytic adenovirus. Mol Ther 2006; 13:928-937. [PMID: 16459149 DOI: 10.1016/j.ymthe.2005.12.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Revised: 12/15/2005] [Accepted: 12/27/2005] [Indexed: 02/04/2023] Open
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the editor-in-chief. Similarities were reported between images in this article and an article in Clinical Cancer Research (Zhou et al., 2005, Clin. Cancer Res. 11, 8431-8440, https://10.1158/1078-0432.CCR-05-1085). Q.J., J.Z., X.H., G.C., Y.L., K.L., L.Z., and D.M. were all authors of the Clinical Cancer Research paper as well. These concerns were initially reported in a Pubpeer thread (https://pubpeer.com/publications/FF881782FF5AFD316D42E0C0F00766). Image analysis performed by the editorial office confirmed findings of image recycling in Figures 2A and 3B of the Molecular Therapy article. This reuse (and in part misrepresentation) of data without appropriate attribution represents a severe abuse of the scientific publishing system.
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MESH Headings
- Adenoviridae/genetics
- Adenoviridae/physiology
- Adenovirus E1A Proteins/deficiency
- Adenovirus E1A Proteins/genetics
- Animals
- Antineoplastic Agents/therapeutic use
- Carcinoma, Hepatocellular/enzymology
- Carcinoma, Hepatocellular/therapy
- Carcinoma, Hepatocellular/virology
- Cell Line
- Cell Line, Tumor
- Cell Survival
- Checkpoint Kinase 1
- Cisplatin/therapeutic use
- Cytopathogenic Effect, Viral/physiology
- DNA, Antisense/genetics
- Female
- Gene Targeting
- Genetic Vectors/administration & dosage
- Genetic Vectors/therapeutic use
- HeLa Cells
- Humans
- Liver Neoplasms/enzymology
- Liver Neoplasms/therapy
- Liver Neoplasms/virology
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Models, Genetic
- Promoter Regions, Genetic
- Protein Kinases/genetics
- Protein Kinases/metabolism
- Virus Replication
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Qinglei Gao
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Jianfeng Zhou
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Xiaoyuan Huang
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Gang Chen
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Fei Ye
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Yunping Lu
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Kanyan Li
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Liang Zhuang
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Mei Huang
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Gang Xu
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Shxuan Wang
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China
| | - Ding Ma
- Cancer Biology Research Center, TongJi Hospital, TongJi Medical School, Huazhong University of Science & Technology, WuHan, Hubei 430030, People's Republic of China.
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27
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Abou El Hassan MAI, Braam SR, Kruyt FAE. A real-time RT-PCR assay for the quantitative determination of adenoviral gene expression in tumor cells. J Virol Methods 2005; 133:53-61. [PMID: 16300837 DOI: 10.1016/j.jviromet.2005.10.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Revised: 10/06/2005] [Accepted: 10/12/2005] [Indexed: 11/21/2022]
Abstract
Oncolytic adenoviruses are exploited as possible anticancer agents in clinical trails. To monitor adenoviral gene expression, a real-time RT-PCR method with a LightCycler was developed that allows the rapid and easy quantification of a number of early and late adenoviral genes in infected tumor cells. Primers were designed that can amplify the spliced forms of the genes encoding E1A13S, DNA polymerase (Pol), pre-terminal protein (pTP), adenoviral death protein (ADP), Hexon (Hex) and Penton (Pent) genes. Standard curves were generated using two-fold serial dilutions of cDNAs derived from non-small cell lung cancer (NSCLC) H460 cells infected for 24h with wild-type adenovirus serotype 5. For all genes correlation coefficients of the standard curves of 0.984 or higher were obtained. The dynamic range of the assay was sufficient to allow the quantitative determination of adenoviral gene expression during a lytic cycle. This RT-PCR assay could be used as a research tool to study the effect of host-cell factors or exogenous treatments on adenoviral gene expression. As example, it is shown that the procedure is suitable to detect changes in adenoviral gene expression in infected H460 cells treated with paclitaxel that is known to enhance the antitumor effect of oncolytic adenoviruses.
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28
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Toth K, Doronin K, Kuppuswamy M, Ward P, Tollefson AE, Wold WSM. Adenovirus immunoregulatory E3 proteins prolong transplants of human cells in immunocompetent mice. Virus Res 2005; 108:149-59. [PMID: 15681065 DOI: 10.1016/j.virusres.2004.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2004] [Revised: 09/01/2004] [Accepted: 09/01/2004] [Indexed: 11/26/2022]
Abstract
The majority of proteins encoded in the early 3 (E3) region of human subgroup C adenoviruses function to modulate the host immune response. For example, gp19K, one of these E3 proteins, prevents the major histocompatibility complex type I (MHC-I) from presenting viral antigens on the surface of the infected cell. Other E3 proteins, such as the RID and 14.7K proteins, counteract the effector phase of the cellular immune response. In order to study further the effects of these proteins, we constructed an E1-/E3- adenovirus vector, Ad/E3, that contains all the E3 genes with the exception of the cytolytic adp gene, inserted into the deleted E1 region. The transcription of the E3 genes in this vector is driven by a CMV promoter in place of the native E3 promoter. Ad/E3 expressed close to wild-type adenovirus levels of all E3 proteins, and these proteins appear to function normally in cell culture. For example, in Ad/E3-infected cells, surface expression of MHC-I was down-regulated, as was cell surface display of death receptors Fas and TRAIL Receptor 1. A human cell line of lung origin (A549), which was rapidly rejected after transplantation into C57BL/6 mice, was protected for an extended time from the host immune response after infection with an Ad/E3, and went through a number of divisions in immunocompetent mice. These latter results indicate that the E3 proteins protect cells from destruction by the immune system.
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Affiliation(s)
- Karoly Toth
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1402 South Grand Blvd., Saint Louis, MO 63104, USA.
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29
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Yun CO, Kim E, Koo T, Kim H, Lee YS, Kim JH. ADP-overexpressing adenovirus elicits enhanced cytopathic effect by induction of apoptosis. Cancer Gene Ther 2005; 12:61-71. [PMID: 15375379 DOI: 10.1038/sj.cgt.7700769] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Replication-competent adenoviruses (Ad's) are emerging as a promising new modality for treatment of cancer. Selective replication of viral agents in tumor may lead to improved efficacy over nonreplicating Ad's due to their inherent ability to multiply, lyse, and spread to surrounding cells. We have previously shown that an E1B 55 kDa-deleted adenovirus (YKL-1) exhibits tumor-specific replication and cell lysis, but its cytolytic effects were reduced in comparison to the wild-type adenovirus. To increase the oncolytic potency of YKL-1, we have reintroduced the Ad death protein (ADP) gene under the control of either a CMV or an MLP promoter at the E3 region of YKL-1, generating YKL-cADP and YKL-mADP Ad's, respectively. ADP is an 11.6 kDa protein encoded by the E3 transcription unit, and is required to kill adenovirus-infected cells efficiently. However, to date, the mechanism by which ADP mediates cell death has not been clearly defined. In this study, we report that ADP-overexpressing Ad markedly enhanced cytolytic effect (up to 100-fold) against all tumor cell lines tested, but did not increase cytopathic effect in normal skin fibroblast, BJ. Moreover, plaque size formed by YKL-cADP was substantially larger than that of YKL-1, indicating an enhancement in cell lysis. TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) assay and Annexin-V/PI double staining indicate that ADP-mediated cytotoxicity was largely driven by apoptosis. Finally, YKL-cADP adenovirus also showed superior antitumor effect than YKL-1 and YKL-mADP in C33A cervical and Hep3B hepatoma xenograft tumor models. Taken together, these lines of evidence demonstrate that the newly generated adenovirus expressing ADP under the CMV promoter induces efficient but tumor-selective cell lysis, which is critical for adding therapeutic value to replicating adenovirus for its use in cancer gene therapy.
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Affiliation(s)
- Chae-Ok Yun
- Brain Korea 21 Project for Medical Sciences, Institute for Cancer Research, Yonsei Cancer Center, Seoul, Korea.
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30
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Kajon AE, Xu W, Erdman DD. Sequence polymorphism in the E3 7.7K ORF of subspecies B1 human adenoviruses. Virus Res 2005; 107:11-9. [PMID: 15567028 DOI: 10.1016/j.virusres.2004.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2003] [Revised: 06/16/2004] [Accepted: 06/16/2004] [Indexed: 10/26/2022]
Abstract
Sequences corresponding to the 7.7K open-reading frame (ORF) of the E3 region of subspecies B1 adenoviruses (Ads) were compared with prototype strains of Ad3, Ad7, Ad16, Ad21, and Ad50 and field isolates representing a variety of genome restriction types of Ad3 and Ad7 to better assess the extent of genetic variation in this intriguing region of the viral genome encoding a product whose function is still unknown. Alignment of 55 species B1 Ad sequences revealed a marked polymorphism in the 7.7K ORF and allowed the identification of eight distinct sequence profiles (SPs) characterized by (1) deletions that retain or change the reading frame, (2) single-base mutations (SBMs) that change the start codon (ATG to ATT or ATC), and (3) other SBMs. mRNAs of expected size for the observed sequence polymorphisms were identified by RT-PCR from DNAse I-treated total RNA extracts of infected cells. Predicted proteins ranged from 0 to 94 amino acids corresponding to molecular masses of 0-11 K. Together with the hypervariable regions of the hexon gene, the E3 7.7K ORF appears to be another area of the Ad genome in which genetic diversity may be generated by illegitimate recombination.
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Affiliation(s)
- A E Kajon
- Lovelace Respiratory Research Institute, Albuquerque, NM, USA
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31
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Zou A, Atencio I, Huang WM, Horn M, Ramachandra M. Overexpression of adenovirus E3-11.6K protein induces cell killing by both caspase-dependent and caspase-independent mechanisms. Virology 2004; 326:240-9. [PMID: 15302210 DOI: 10.1016/j.virol.2004.06.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2004] [Accepted: 06/01/2004] [Indexed: 11/17/2022]
Abstract
Recent studies have shown enhanced antitumor efficacy with adenoviruses that either lack E1B-19K or overexpress E3-11.6K (also known as adenoviral death protein). E1B-19K is a well-characterized anti-apoptotic protein, and viruses with E1B-19K deletions show increased cytopathicity. However, the mechanism of cell killing by E3-11.6K, which plays an important role in killing infected cells and virion release, is not well characterized. To understand the mechanism of cell killing following E3-11.6K overexpression, we constructed a recombinant adenovirus, Ad-ME, by introducing viral major late promoter upstream of the E3-11.6K sequence. Similar to the E1B-19K-deleted virus, E1B/19K-, Ad-ME induced cell death to a greater extent than the wild-type virus. Cell shrinkage, membrane blebbing, activation of caspases 3 and 9, cleavage of poly(ADP-ribose)polymerase (PARP), DNA degradation, and ratio of ADP to ATP in Ad-ME-infected cells indicated that apoptosis contributes to cell death following E3-11.6K overexpression. However, the levels of activation of caspases 3 and 9 were lower in cells infected with Ad-ME compared to those infected with E1B/19K-. Furthermore, cell killing by Ad-ME was not effectively inhibited by Z-VAD-FMK, a general caspase inhibitor. Taken together, our results suggest both caspase-dependent and caspase-independent mechanisms of cell killing due to overexpression of E3-11.6K.
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Affiliation(s)
- Aihua Zou
- Canji, Inc., San Diego, CA 92128, USA
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32
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Toth K, Djeha H, Ying B, Tollefson AE, Kuppuswamy M, Doronin K, Krajcsi P, Lipinski K, Wrighton CJ, Wold WSM. An oncolytic adenovirus vector combining enhanced cell-to-cell spreading, mediated by the ADP cytolytic protein, with selective replication in cancer cells with deregulated wnt signaling. Cancer Res 2004; 64:3638-44. [PMID: 15150123 DOI: 10.1158/0008-5472.can-03-3882] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have constructed a novel oncolytic adenovirus (Ad) vector named VRX-009 that combines enhanced cell spread with tumor-specific replication. Enhanced spread, which could significantly increase antitumor efficacy, is mediated by overexpression of the Ad cytolytic protein named ADP (also known as E3-11.6K). Replication of VRX-009 is restricted to cells with a deregulated wnt signal transduction pathway by replacement of the wild-type Ad E4 promoter with a synthetic promoter consisting of five consensus binding sites for the T-cell factor transcription factor. Tumor-selective replication is indicated by several lines of evidence. VRX-009 expresses E4ORF3, a representative Ad E4 protein, only in colon cancer cell lines. Furthermore, VRX-009 replicates preferentially in colon cancer cell lines as evidenced by virus productivity 2 orders of magnitude higher in SW480 colon cancer cells than in A549 lung cancer cells. Replication in primary human bronchial epithelial cells and human umbilical vein endothelial cells was also significantly lower than in SW480 cells. When tested in human tumor xenografts in nude mice, VRX-009 effectively suppressed the growth of SW480 colon tumors but not of A549 lung tumors. VRX-009 may provide greater level of antitumor efficacy than standard oncolytic Ad vectors in tumors in which a defect in wnt signaling increases the level of nuclear beta-catenin.
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Affiliation(s)
- Karoly Toth
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri 63126, USA
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33
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Lichtenstein DL, Toth K, Doronin K, Tollefson AE, Wold WSM. Functions and mechanisms of action of the adenovirus E3 proteins. Int Rev Immunol 2004; 23:75-111. [PMID: 14690856 DOI: 10.1080/08830180490265556] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In the evolutionary battle between viruses and their hosts, viruses have armed themselves with weapons to defeat the host's attacks on infected cells. Various proteins encoded in the adenovirus (Ad) E3 transcription unit protect cells from killing mediated by cytotoxic T cells and death-inducing cytokines such as tumor necrosis factor (TNF), Fas ligand, and TNF-related apoptosis-inducing ligand (TRAIL). The viral protein E3-gp19 K blocks MHC class-I-restricted antigen presentation, which diminishes killing by cytotoxic T cells. The receptor internalization and degradation (RID) complex (formerly E3-10.4 K/14.5 K) stimulates the clearance from the cell surface and subsequent degradation of the receptors for Fas ligand and TRAIL, thereby preventing the action of these important immune mediators. RID also downmodulates the epidermal growth factor receptor (EGFR), although what role, if any, this function has in immune regulation is uncertain. In addition, RID antagonizes TNF-mediated apoptosis and inflammation through a mechanism that does not primarily involve receptor downregulation. E3-6.7 K functions together with RID in downregulating some TRAIL receptors and may block apoptosis independently of other E3 proteins. Furthermore, E3-14.7 K functions as a general inhibitor of TNF-mediated apoptosis and blocks TRAIL-induced apoptosis. Finally, after expending great effort to maintain cell viability during the early part of the virus replication cycle, Ads lyse the cell to allow efficient virus release and dissemination. To perform this task subgroup C Ads synthesize a protein late in infection named ADP (formerly E3-11.6 K) that is required for efficient virus release. This review focuses on recent experiments aimed at discovering the mechanism of action of these critically important viral proteins.
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Affiliation(s)
- Drew L Lichtenstein
- Department of Molecular Microbiology and Immunology, Saint Louis University Health Sciences Center, St. Louis, Missouri 63104, USA
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34
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Windheim M, Hilgendorf A, Burgert HG. Immune Evasion by Adenovirus E3 Proteins: Exploitation of Intracellular Trafficking Pathways. Curr Top Microbiol Immunol 2004; 273:29-85. [PMID: 14674598 DOI: 10.1007/978-3-662-05599-1_2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Adenoviruses (Ads) are nonenveloped viruses which replicate and assemble in the nucleus. Therefore, viral membrane proteins are not directly required for their multiplication. Yet, all human Ads encode integral membrane proteins in the early transcription unit 3 (E3). Previous studies on subgenus C Ads demonstrated that most E3 proteins exhibit immunomodulatory functions. In this review we focus on the E3 membrane proteins, which appear to be primarily devoted to remove critical recognition structures for the host immune system from the cell surface. The molecular mechanism for removal depends on the E3 protein involved: E3/19K prevents expression of newly synthesized MHC molecules by inhibition of ER export, whereas E3/10.4-14.5K down-regulate apoptosis receptors by rerouting them into lysosomes. The viral proteins mediating these processes contain typical transport motifs, such as KKXX, YXXphi, or LL. E3/49K, another recently discovered E3 protein, may require such motifs to reach a processing compartment essential for its presumed immunomodulatory activity. Thus, E3 membrane proteins exploit the intracellular trafficking machinery for immune evasion. Conspicuously, many E3 membrane proteins from Ads other than subgenus C also contain putative transport motifs. Close inspection of surrounding amino acids suggests that many of these are likely to be functional. Therefore, Ads might harbor more E3 proteins that exploit intracellular trafficking pathways as a means to manipulate immunologically important key molecules. Differential expression of such functions by Ads of different subgenera may contribute to their differential pathogenesis. Thus, an unexpected link emerges between viral manipulation of intracellular transport pathways and immune evasion.
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Affiliation(s)
- M Windheim
- Aventis, DG Metabolic Diseases, 65926 Frankfurt, Germany
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35
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Ying B, Wold WSM. Adenovirus ADP protein (E3-11.6K), which is required for efficient cell lysis and virus release, interacts with human MAD2B. Virology 2003; 313:224-34. [PMID: 12951035 DOI: 10.1016/s0042-6822(03)00287-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The human subgroup C adenovirus (Ad) protein named adenovirus death protein (ADP) (previously named E3-11.6K) is synthesized at very late stages of infection when it mediates efficient lysis of cells and release of adenovirus to infect other cells. ADP is an integral membrane N-linked, O-linked palmitoylated glycoprotein of 101 amino acids (aa) that localizes to the nuclear membrane, endoplasmic reticulum (ER), and Golgi. It has a single membrane spanning region (roughly aa 40-60) and is oriented with aa 1-40 in the lumen and aa 61-101 in the nucleoplasm and cytoplasm. Using aa 61-101 of Ad2 ADP as bait in a yeast two-hybrid screen, we isolated a cDNA for a 211-aa protein that initially was not in the database but has now been published by others with the names human MAD2B, MAD2L2, and REV7. ADP binds strongly to human MAD2B not only in yeast but also in GST pull-down experiments and in coimmunoprecipitations of ADP and MAD2B synthesized in vitro or in vivo. ADP mutants with deletions throughout the bait region do not interact with human MAD2B, whereas a Pro69Pro70 to Ala69Ala70 mutant in the "basic-proline" domain of ADP does interact. Northern blot analyses indicate that human MAD2B is expressed ubiquitously. Human MAD2B is about 25% identical to human MAD2, a spindle assembly checkpoint protein. Two human A549 cell lines were made that constitutively overexpress MAD2B. Wild-type adenovirus lyses these cells significantly more slowly than it lyses parental A549 cells, raising the possibility that ADP and MAD2B act in opposition and suggesting that the ADP-MAD2B interaction is biologically relevant.
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Affiliation(s)
- Baoling Ying
- Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, MO 63104, USA
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36
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Tollefson AE, Scaria A, Ying B, Wold WSM. Mutations within the ADP (E3-11.6K) protein alter processing and localization of ADP and the kinetics of cell lysis of adenovirus-infected cells. J Virol 2003; 77:7764-78. [PMID: 12829816 PMCID: PMC161948 DOI: 10.1128/jvi.77.14.7764-7778.2003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
ADP (also known as E3-11.6K protein) is synthesized abundantly in late adenovirus infection and is required for efficient lysis of infected cells and release of viral progeny at the end of the viral replication cycle. ADP is a type III bitopic N(endo)C(exo) nuclear membrane and Golgi glycoprotein that is produced at high levels in late adenovirus infection (>24 h postinfection). We show pulse-chase and other studies indicating that ADP undergoes a complex process of N- and O-linked glycosylation and proteolytic cleavage. In order to further characterize ADP, a series of 23 deletion and point mutations has been constructed in the adenovirus serotype 2 adp gene and then built into a wild-type adenovirus background. These mutants were analyzed for processing and intracellular localization of ADP. Mutation of the single predicted N glycosylation site eliminated N glycosylation. Deletion of a region in ADP rich in serine and threonine residues reduced O glycosylation. In general, mutations within the lumenal domain of ADP resulted in lower protein stability; immunofluorescence assays indicated that these ADPs were primarily present in the Golgi apparatus. Viruses with mutations within the cytoplasmic-nucleoplasmic domain of ADP showed normal glycosylation patterns and protein abundance for ADP, but the protein was often found throughout cellular membranes rather than being localized specifically to the nuclear membrane and Golgi apparatus. The ADP virus mutants were analyzed by cell viability assays to determine the kinetics of cell lysis following infection of human A549 cells. In general, viruses with mutations within the lumenal domain of ADP display greatly reduced efficiencies of cell lysis. Viruses with large deletions in the cytoplasmic-nucleoplasmic domain of ADP retain much of their ability to lyse infected cells.
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Affiliation(s)
- Ann E Tollefson
- Department of Molecular Microbiology and Immunology, St. Louis University Health Sciences Center, 1402 S. Grand Boulevard, St. Louis, MO 63104, USA
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37
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Affiliation(s)
- Karoly Toth
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1402 S. Grand Blvd., St. Louis, MO 63104, USA
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38
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Doronin K, Toth K, Kuppuswamy M, Krajcsi P, Tollefson AE, Wold WSM. Overexpression of the ADP (E3-11.6K) protein increases cell lysis and spread of adenovirus. Virology 2003; 305:378-87. [PMID: 12573583 DOI: 10.1006/viro.2002.1772] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adenoviruses replicate in the nucleus and induce lytic cell death. We have shown previously that efficient cell lysis and release of adenovirus from infected cells requires an 11.6-kDa protein named Adenovirus Death Protein (ADP). The adp gene is located in the early E3 transcription unit, but the gene is expressed primarily at very late stages of infection. The putative function of ADP was discerned previously from the use of virus mutants that lack functional ADP. Here we describe two adenovirus mutants, named VRX-006 and VRX-007, that overexpress ADP. VRX-006 lacks all other genes in the E3 region, and VRX-007 lacks all other E3 genes except 12.5K. VRX-006 and VRX-007 display the phenotype predicted by the proposed function for ADP: they produce early cytopathic effect, early cell lysis, large plaques, and increased cell-to-cell spread. They grow as well in cultured cells as does adenovirus type 5. These results are consistent with the conclusion that ADP functions in adenovirus infections to promote virus release from cells at the culmination of infection.
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Affiliation(s)
- Konstantin Doronin
- Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, Missouri 63104, USA
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39
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Nemunaitis J, Edelman J. Selectively replicating viral vectors. Cancer Gene Ther 2002; 9:987-1000. [PMID: 12522438 DOI: 10.1038/sj.cgt.7700547] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2002] [Indexed: 01/26/2023]
Affiliation(s)
- John Nemunaitis
- US Oncology, Inc., Collins Building, 5th Floor, Dallas, Texas 75246, USA.
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40
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Abstract
We examined the transcriptional organization of fowl adenovirus 9 (FAdV-9) and analyzed temporal transcription profiles of its early and late mRNAs. At least six early and six late transcriptional regions were identified for FAdV-9. Extensive splicing was observed in all FAdV-9 early transcripts examined. Sequence analysis of the cDNAs representing the early proteins identified untranslated leader sequences, precise locations of splice donor and acceptor sites, as well as polyadenylation signals and polyadenylation sites. A unique characteristic, compared to other adenoviruses, was the detection by RT-PCR of multiple transcripts specific for each of five late genes (protein III, pVII, pX, 100K, and fiber), suggesting that FAdV-9 late transcripts undergo more extensive splicing than reported for other adenoviruses.
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Affiliation(s)
- Davor Ojkic
- Department of Pathobiology, Ontario Veterinary College, College of Biological Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
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41
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Windheim M, Burgert HG. Characterization of E3/49K, a novel, highly glycosylated E3 protein of the epidemic keratoconjunctivitis-causing adenovirus type 19a. J Virol 2002; 76:755-66. [PMID: 11752165 PMCID: PMC136837 DOI: 10.1128/jvi.76.2.755-766.2002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The early transcription unit 3 (E3) of human adenoviruses (Ads) encodes proteins with various immunomodulatory functions. Ads from different subgenera differ considerably in their E3 coding capacity, suggesting that distinct sets of immunomodulatory E3 proteins may influence the disease pattern associated with different Ad subgenera. Interestingly, the E3 region of Ads classified in subgenus D, which are often isolated from AIDS patients and have the propensity to cause eye infections, contains a unique gene, named E3/49K, that may encode a protein with a calculated molecular weight of 48,984 that might be implicated in diseases caused by this subgenus. The 49K sequence predicts a highly glycosylated type I transmembrane protein with a short cytoplasmic tail containing two motifs, YXXPhi and LL, potentially involved in targeting the protein to endosomal or lysosomal compartments. Remarkably, the 49K protein is predicted to contain an unusual immunoglobulin-like fold. Here we have characterized the E3/49K protein of Ad type 19a, an Ad of subgenus D which causes epidemic keratoconjunctivitis. E3/49K was synthesized as an 80- to 100-kDa protein, which is unusually large for an E3 protein. In contrast to another early protein, E3/19K, the expression of E3/49K started early but continued throughout the infection cycle. Analysis of the 49K glycosylation revealed that the majority of 49K molecules contained only 12 of the predicted 14 N-glycans. Furthermore, we provide evidence that 49K is O-glycosylated. At steady state, E3/49K was localized in the Golgi-trans-Golgi network and in early endosomes. Interestingly, the 49K protein has a rather short half-life and seems to be proteolytically cleaved. A processing pattern similar to that in the early stages of infection is seen in transfected cells, constitutively expressing 49K in the absence of other Ad proteins. Together, our data provide the first biochemical and cell biological characterization of an unique E3 protein of subgenus D Ads.
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Affiliation(s)
- Mark Windheim
- Max-von-Pettenkofer Institute, Gene Center, Ludwig-Maximilians-University, 81377 Munich, Germany
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42
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Ramachandra M, Rahman A, Zou A, Vaillancourt M, Howe JA, Antelman D, Sugarman B, Demers GW, Engler H, Johnson D, Shabram P. Re-engineering adenovirus regulatory pathways to enhance oncolytic specificity and efficacy. Nat Biotechnol 2001; 19:1035-41. [PMID: 11689848 DOI: 10.1038/nbt1101-1035] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Replicating adenoviruses may prove to be effective anticancer agents if they can be engineered to selectively destroy tumor cells. We have constructed a virus (01/PEME) containing a novel regulatory circuit in which p53-dependent expression of an antagonist of the E2F transcription factor inhibits viral replication in normal cells. In tumor cells, however, the combination of p53 pathway defects and deregulated E2F allows replication of 01/PEME at near wild-type levels. The re-engineered virus also showed significantly enhanced efficacy compared with extensively studied E1b-deleted viruses such as dl1520 in human xenograft tumor models.
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Affiliation(s)
- M Ramachandra
- Canji, Inc. 3525 John Hopkins Court, San Diego, CA 92121, USA.
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43
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Hawkins LK, Hermiston TW. Gene delivery from the E3 region of replicating human adenovirus: evaluation of the ADP region. Gene Ther 2001; 8:1132-41. [PMID: 11509943 DOI: 10.1038/sj.gt.3301508] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2000] [Accepted: 05/22/2001] [Indexed: 11/08/2022]
Abstract
Genetically modified replication-selective human adenoviruses are currently undergoing testing in the clinical setting as anticancer agents. Coupling the lytic function of these viruses with virus-mediated transgene delivery represents a powerful extension of this treatment. We have designed a unique system for gene delivery from the replicating virus. It takes advantage of the endogenous gene expression control sequences (promoter, splicing, polyadenylation signals) to efficiently and predictably deliver transgenes from the non-essential E3 transcription unit while still maintaining the expression of the remaining E3 genes in the multi-gene transcription unit. In this article, we engineered restriction enzyme sites into the virus genome selectively to delete the ADP gene and replace it with the therapeutic transgenes CD and TNFalpha. We demonstrate that: (1) transgene expression from this region mirrors the substituted ADP gene; (2) the loss of ADP in these viruses results in infected cells with extended viability and protein synthesis when compared with a wild-type Ad5 infected cell; and (3) expression of surrounding E3 genes can be maintained in such a system. The potential advantages of delivering transgenes from the ADP region of the replicating adenovirus are discussed.
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Affiliation(s)
- L K Hawkins
- Onyx Pharmaceuticals, 3031 Research Drive, Richmond, CA 94806, USA
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44
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Doronin K, Kuppuswamy M, Toth K, Tollefson AE, Krajcsi P, Krougliak V, Wold WS. Tissue-specific, tumor-selective, replication-competent adenovirus vector for cancer gene therapy. J Virol 2001; 75:3314-24. [PMID: 11238857 PMCID: PMC114124 DOI: 10.1128/jvi.75.7.3314-3324.2001] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2000] [Accepted: 01/05/2001] [Indexed: 12/25/2022] Open
Abstract
We have previously described two replication-competent adenovirus vectors, named KD1 and KD3, for potential use in cancer gene therapy. KD1 and KD3 have two small deletions in the E1A gene that restrict efficient replication of these vectors to human cancer cell lines. These vectors also have increased capacity to lyse cells and spread from cell to cell because they overexpress the adenovirus death protein, an adenovirus protein required for efficient cell lysis and release of adenovirus from the cell. We now describe a new vector, named KD1-SPB, which is the KD1 vector with the E4 promoter replaced by the promoter for surfactant protein B (SPB). SPB promoter activity is restricted in the adult to type II alveolar epithelial cells and bronchial epithelial cells. Because KD1-SPB has the E1A mutations, it should replicate within and destroy only alveolar and bronchial cancer cells. We show that KD1-SPB replicates, lyses cells, and spreads from cell to cell as well as does KD1 in H441 cells, a human cancer cell line where the SPB promoter is active. KD1-SPB replicates, lyses cells, and spreads only poorly in Hep3B liver cancer cells. Replication was determined by expression of the E4ORF3 protein, viral DNA accumulation, fiber synthesis, and virus yield. Cell lysis and vector spread were measured by lactate dehydrogenase release and a "vector spread" assay. In addition to Hep3B cells, KD1-SPB also did not express E4ORF3 in HT29.14S (colon), HeLa (cervix), KB (nasopharynx), or LNCaP (prostate) cancer cell lines, in which the SPB promoter is not expected to be active. Following injection into H441 or Hep3B tumors growing in nude mice, KD1-SPB caused a three- to fourfold suppression of growth of H441 tumors, similar to that seen with KD1. KD1-SPB had only a minimal effect on the growth of Hep3B tumors, whereas KD1 again caused a three- to fourfold suppression. These results establish that the adenovirus E4 promoter can be replaced by a tissue-specific promoter in a replication-competent vector. The vector has three engineered safety features: the tissue-specific promoter, the mutations in E1A that preclude efficient replication in nondividing cells, and a deletion of the E3 genes which shield the virus from attack by the immune system. KD1-SPB may have use in treating human lung cancers in which the SPB promoter is active.
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Affiliation(s)
- K Doronin
- Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, St. Louis, Missouri, USA
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45
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Reddy PS, Idamakanti N, Zakhartchouk LN, Babiuk LA, Mehtali M, Tikoo SK. Optimization of bovine coronavirus hemagglutinin-estrase glycoprotein expression in E3 deleted bovine adenovirus-3. Virus Res 2000; 70:65-73. [PMID: 11074126 PMCID: PMC7126343 DOI: 10.1016/s0168-1702(00)00209-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Adenoviral vectors expressing foreign genes have many desirable properties in applications such as vaccination. Recently, we have generated replication-competent (E3 deleted) bovine adenovirus-3 (BAV-3) recombinants expressing significant amounts of glycoprotein D (gD) of bovine herpesvirus-1 (a DNA virus). However, attempts to express the RNA virus genes using the same strategy were not successful. In an effort to optimize the expression, we have constructed several BAV-3 recombinants carrying the hemagglutinin esterase (HE) gene of bovine coronavirus (BCV) in the E3 region with or without exogenous transcription control elements. The expression studies suggest that the introduction of a 137 bp chimeric intron upstream of the HE cDNA is able to increase the level of HE gene expression. The introduction of a SV40 early promoter or human cytomegalovirus (HCMV) immediate early (IE) promoter into the expression cassette changed the kinetics of the HE expression. However, the recombinant BAV-3 containing HE under the HCMV IE promoter replicated less efficiently than the wild-type BAV-3. These studies should prove useful in expression of other RNA viral genes in the E3 region of BAV-3 expression system.
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Affiliation(s)
- P S Reddy
- Virology group, Veterinary Infectious Disease Organization, University of Saskatchewan, Saskatoon, S7N 5E3, Saskatchewan, Canada
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Li Y, Wold WS. Identification and characterization of a 30K protein (Ad4E3-30K) encoded by the E3 region of human adenovirus type 4. Virology 2000; 273:127-38. [PMID: 10891415 DOI: 10.1006/viro.2000.0384] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human adenovirus type 4 (Ad4), the sole member of subgroup E, contains an open reading frame in the E3 region predicted to encode a unique 30-kDa protein (named Ad4E3-30K). Ad4E3-30K is predicted to be an integral membrane protein containing an N-terminal signal sequence, a lumenal domain, a transmembrane domain near the C-terminus, and a 37-amino-acid cytoplasmic tail. To determine whether this protein is expressed, rabbit polyclonal antisera were raised against 30K-containing fusion proteins expressed in bacteria. A 30K protein was detected by immunoprecipitation from cell-free translation products and from Ad4-infected A549 cells radiolabeled in the presence of tunicamycin. The protein was detected at only low levels in infected cells. It was not synthesized by a mutant with a large E3 deletion that includes the Ad4E3-30K gene. This mutant grows as well as wild-type Ad4 in culture. Features of Ad4E3-30K were characterized in different transient expression systems. The protein underwent glycosylation by addition of approximately six asparagine-linked oligosaccharides. These glycans were sensitive to endoglycosidase H, indicating that they were either high-mannose or hybrid types, but not complex types, and that the protein did not pass through the Golgi apparatus. Immunofluorescence staining of transfected cells revealed that Ad4E3-30K was localized primarily in the endoplasmic reticulum and nuclear envelope.
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Affiliation(s)
- Y Li
- Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, Missouri, 63104, USA
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Doronin K, Toth K, Kuppuswamy M, Ward P, Tollefson AE, Wold WS. Tumor-specific, replication-competent adenovirus vectors overexpressing the adenovirus death protein. J Virol 2000; 74:6147-55. [PMID: 10846098 PMCID: PMC112113 DOI: 10.1128/jvi.74.13.6147-6155.2000] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/1999] [Accepted: 03/28/2000] [Indexed: 11/20/2022] Open
Abstract
We have constructed two novel adenovirus (Ad) replication-competent vectors, named KD1 and KD3, that may have use in anticancer therapy. The vectors have two key features. First, they markedly overexpress the Ad death protein (ADP), an Ad nuclear membrane glycoprotein required at late stages of infection for efficient cell lysis and release of Ad from cells. Overexpression of ADP was achieved by deleting the E3 region and reinserting the adp gene. Because ADP is overexpressed, KD1 and KD3 are expected to spread more rapidly and effectively through tumors. Second, KD1 and KD3 have two E1A mutations (from the mutant dl1101/1107) that prevent efficient replication in nondividing cells but allow replication in dividing cancer cells. These E1A mutations preclude binding of E1A proteins to p300 and pRB. As a result, the virus should not be able to drive cells from G(0) to S phase and therefore should not be able to replicate in normal tissues. We show that KD1 and KD3 do not replicate well in quiescent HEL-299 cells or in primary human bronchial epithelial cells, small airway epithelial cells, or endothelial cells; however, they replicate well in proliferating HEL-299 cells and human A549 lung carcinoma cells. In cultured A549 cells, KD1 and KD3 lyse cells and spread from cell to cell more rapidly than their control virus, dl1101/1107, or wild-type Ad. They are also more efficient than dl1101/1107 or wild-type Ad in complementing the spread from cell to cell of an E1(-) E3(-) replication-defective vector expressing beta-galactosidase. A549 cells form rapidly growing solid tumors when injected into the hind flanks of immunodeficient nude mice; however, when A549 cells were infected with 10(-4) PFU of KD3/cell prior to injection into mice, tumor formation was nearly completely suppressed. When established A549 tumors in nude mice were examined, tumors injected with buffer grew 13.3-fold over 5 weeks, tumors injected with dl1101/1107 grew 8-fold, and tumors injected with KD1 or KD3 grew 2.6-fold. Hep 3B tumors injected with buffer grew 12-fold over 3.5 weeks, whereas tumors injected with KD1 or KD3 grew 4-fold. We conclude that KD1 and KD3 show promise as anticancer therapeutics.
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Affiliation(s)
- K Doronin
- Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, MO 63104, USA
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Abstract
Successful viral replication requires not only the efficient production and spread of progeny, but also evasion of host defense mechanisms that limit replication by killing infected cells. In addition to inducing immune and inflammatory responses, infection by most viruses triggers apoptosis or programmed cell death of the infected cell. This cell response often results as a compulsory or unavoidable by-product of the action of critical viral replicative functions. In addition, some viruses seem to use apoptosis as a mechanism of cell killing and virus spread. In both cases, successful replication relies on the ability of certain viral products to block or delay apoptosis until sufficient progeny have been produced. Such proteins target a variety of strategic points in the apoptotic pathway. In this review we summarize the great amount of recent information on viruses and apoptosis and offer insights into how this knowledge may be used for future research and novel therapies.
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Affiliation(s)
- A Roulston
- GeminX Biotechnologies Inc., Montreal, Quebec, Canada.
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Cauthen AN, Spindler KR. Novel expression of mouse adenovirus type 1 early region 3 gp11K at late times after infection. Virology 1999; 259:119-28. [PMID: 10364495 DOI: 10.1006/viro.1999.9713] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mutations were introduced into mouse adenovirus type 1 (MAV-1) early region 3 (E3) initiator codons by homologous recombination between viral DNA and a plasmid containing a mutagenized E3 region. The resulting mutant virus, pmE312, contained ATG --> TTA mutations at codon positions 1 and 4 and was expected to be null for the expression of the E3 proteins. However, gp11K, an MAV-1 E3 glycoprotein of 14K molecular weight, was detected in mutant-infected cell lysates at levels about 10-12% of that of wild-type (wt) virus at late times in infection. The gp11K polypeptide produced by pmE312 at late times was immunoprecipitated with two E3-specific antisera prepared against different regions of the protein. Like gp11K produced by wt virus infections, it was sensitive to endoglycosidase H (endo H) and thus resident in the endoplasmic reticulum (ER). In pmE312-infected cells treated with cytosine arabinoside (araC), an inhibitor of DNA replication, the gp11K protein was not detected by immunoprecipitation. This indicates that gp11K expression in pmE312-infected cells at late times was dependent on DNA replication and that it was thus translated from a late transcript. In vitro translation of poly(A)+ RNA from mock-, wild-type-, and pmE312-infected cells showed that gp11K was translated from late mRNA as an approximately 28K fusion between a late protein and gp11K. Our data are consistent with a model in which gp11K is expressed at late times as a late protein-gp11K chimera in both wt- and mutant-infected cells. This chimera is then processed: removal of a large N-terminal sequence results in the observed 14K ER-localized gp11K.
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Affiliation(s)
- A N Cauthen
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA
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Adenovirus E3 Proteins: 14.7K, RID, and gp19K Inhibit Immune-Induced Cell Death; Adenovirus Death Protein Promotes Cell Death. ACTA ACUST UNITED AC 1998. [DOI: 10.1006/smvy.1998.0156] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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