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Chen M, Yang C, Zhai X, Wang C, Liu M, Zhang B, Guo X, Wang Y, Li H, Liu Y, Han J, Wang X, Li J, Jia L, Li L. Comprehensive Identification and Characterization of HML-9 Group in Chimpanzee Genome. Viruses 2024; 16:892. [PMID: 38932184 PMCID: PMC11209481 DOI: 10.3390/v16060892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 05/23/2024] [Accepted: 05/27/2024] [Indexed: 06/28/2024] Open
Abstract
Endogenous retroviruses (ERVs) are related to long terminal repeat (LTR) retrotransposons, comprising gene sequences of exogenous retroviruses integrated into the host genome and inherited according to Mendelian law. They are considered to have contributed greatly to the evolution of host genome structure and function. We previously characterized HERV-K HML-9 in the human genome. However, the biological function of this type of element in the genome of the chimpanzee, which is the closest living relative of humans, largely remains elusive. Therefore, the current study aims to characterize HML-9 in the chimpanzee genome and to compare the results with those in the human genome. Firstly, we report the distribution and genetic structural characterization of the 26 proviral elements and 38 solo LTR elements of HML-9 in the chimpanzee genome. The results showed that the distribution of these elements displayed a non-random integration pattern, and only six elements maintained a relatively complete structure. Then, we analyze their phylogeny and reveal that the identified elements all cluster together with HML-9 references and with those identified in the human genome. The HML-9 integration time was estimated based on the 2-LTR approach, and the results showed that HML-9 elements were integrated into the chimpanzee genome between 14 and 36 million years ago and into the human genome between 18 and 49 mya. In addition, conserved motifs, cis-regulatory regions, and enriched PBS sequence features in the chimpanzee genome were predicted based on bioinformatics. The results show that pathways significantly enriched for ERV LTR-regulated genes found in the chimpanzee genome are closely associated with disease development, including neurological and neurodevelopmental psychiatric disorders. In summary, the identification, characterization, and genomics of HML-9 presented here not only contribute to our understanding of the role of ERVs in primate evolution but also to our understanding of their biofunctional significance.
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Affiliation(s)
- Mingyue Chen
- National 111 Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering, Hubei University of Technology, Wuhan 430068, China;
| | - Caiqin Yang
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Xiuli Zhai
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei 230032, China
| | - Chunlei Wang
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei 230032, China
| | - Mengying Liu
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Bohan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Xing Guo
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei 230032, China
| | - Yanglan Wang
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Hanping Li
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Yongjian Liu
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Jingwan Han
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Xiaolin Wang
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Jingyun Li
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Lei Jia
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
| | - Lin Li
- State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, Beijing 100071, China; (C.Y.); (X.Z.); (C.W.); (M.L.); (B.Z.); (X.G.); (Y.W.); (H.L.); (Y.L.); (J.H.); (X.W.); (J.L.)
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2
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Armani-Tourret M, Gao C, Hartana CA, Sun W, Carrere L, Vela L, Hochroth A, Bellefroid M, Sbrolla A, Shea K, Flynn T, Roseto I, Rassadkina Y, Lee C, Giguel F, Malhotra R, Bushman FD, Gandhi RT, Yu XG, Kuritzkes DR, Lichterfeld M. Selection of epigenetically privileged HIV-1 proviruses during treatment with panobinostat and interferon-α2a. Cell 2024; 187:1238-1254.e14. [PMID: 38367616 PMCID: PMC10903630 DOI: 10.1016/j.cell.2024.01.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 11/26/2023] [Accepted: 01/24/2024] [Indexed: 02/19/2024]
Abstract
CD4+ T cells with latent HIV-1 infection persist despite treatment with antiretroviral agents and represent the main barrier to a cure of HIV-1 infection. Pharmacological disruption of viral latency may expose HIV-1-infected cells to host immune activity, but the clinical efficacy of latency-reversing agents for reducing HIV-1 persistence remains to be proven. Here, we show in a randomized-controlled human clinical trial that the histone deacetylase inhibitor panobinostat, when administered in combination with pegylated interferon-α2a, induces a structural transformation of the HIV-1 reservoir cell pool, characterized by a disproportionate overrepresentation of HIV-1 proviruses integrated in ZNF genes and in chromatin regions with reduced H3K27ac marks, the molecular target sites for panobinostat. By contrast, proviruses near H3K27ac marks were actively selected against, likely due to increased susceptibility to panobinostat. These data suggest that latency-reversing treatment can increase the immunological vulnerability of HIV-1 reservoir cells and accelerate the selection of epigenetically privileged HIV-1 proviruses.
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Affiliation(s)
| | - Ce Gao
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Ciputra Adijaya Hartana
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - WeiWei Sun
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | - Leah Carrere
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Liliana Vela
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA
| | | | | | - Amy Sbrolla
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Katrina Shea
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Theresa Flynn
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Isabelle Roseto
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Carole Lee
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Francoise Giguel
- Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Rajeev Malhotra
- Division of Cardiology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Frederic D Bushman
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rajesh T Gandhi
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Xu G Yu
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel R Kuritzkes
- Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mathias Lichterfeld
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA 02139, USA; Division of Infectious Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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3
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Wang C, Zhai X, Wang S, Zhang B, Yang C, Song Y, Li H, Liu Y, Han J, Wang X, Li J, Chen M, Jia L, Li L. Comprehensive characterization of ERV-K (HML-8) in the chimpanzee genome revealed less genomic activity than humans. Front Cell Infect Microbiol 2024; 14:1349046. [PMID: 38456081 PMCID: PMC10918009 DOI: 10.3389/fcimb.2024.1349046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 02/06/2024] [Indexed: 03/09/2024] Open
Abstract
Endogenous retroviruses (ERVs) originate from ancestral germline infections caused by exogenous retroviruses. Throughout evolution, they have become fixed within the genome of the animals into which they were integrated. As ERV elements coevolve with the host, they are normally epigenetically silenced and can become upregulated in a series of physiological and pathological processes. Generally, a detailed ERV profile in the host genome is critical for understanding the evolutionary history and functional performance of the host genome. We previously characterized and cataloged all the ERV-K subtype HML-8 loci in the human genome; however, this has not been done for the chimpanzee, the nearest living relative of humans. In this study, we aimed to catalog and characterize the integration of HML-8 in the chimpanzee genome and compare it with the integration of HML-8 in the human genome. We analyzed the integration of HML-8 and found that HML-8 pervasively invaded the chimpanzee genome. A total of 76 proviral elements were characterized on 23/24 chromosomes, including detailed elements distribution, structure, phylogeny, integration time, and their potential to regulate adjacent genes. The incomplete structure of HML-8 proviral LTRs will undoubtedly affect their activity. Moreover, the results indicated that HML-8 integration occurred before the divergence between humans and chimpanzees. Furthermore, chimpanzees include more HML-8 proviral elements (76 vs. 40) and fewer solo long terminal repeats (LTR) (0 vs. 5) than humans. These results suggested that chimpanzee genome activity is less than the human genome and that humans may have a better ability to shape and screen integrated proviral elements. Our work is informative in both an evolutionary and a functional context for ERVs.
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Affiliation(s)
- Chunlei Wang
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Xiuli Zhai
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Shibo Wang
- National 111 Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering, Hubei University of Technology, Wuhan, Hubei, China
| | - Bohan Zhang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Caiqin Yang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Yanmei Song
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Hanping Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Yongjian Liu
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Jingwan Han
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Xiaolin Wang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Jingyun Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Mingyue Chen
- National 111 Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering, Hubei University of Technology, Wuhan, Hubei, China
| | - Lei Jia
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Lin Li
- Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, China
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4
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Mantovani F, Kitsou K, Paraskevis D, Lagiou P, Magiorkinis G. The interaction of human immunodeficiency virus-1 and human endogenous retroviruses in patients (primary cell cultures) and cell line models. Microbiol Spectr 2023; 11:e0137923. [PMID: 37811936 PMCID: PMC10715072 DOI: 10.1128/spectrum.01379-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/24/2023] [Indexed: 10/10/2023] Open
Abstract
IMPORTANCE In this work, we demonstrated that human immunodeficiency virus (HIV) infection leads to the modification of the human endogenous retrovirus (HERV) expression. Differential expression of multiple HERVs was found in peripheral blood mononuclear cells derived from HIV-infected patients compared to healthy donors and HIV-infected T cell cultures compared to non-infected. The effect of HIV presence on HERV expression appears to be more restricted in cells of monocytic origin, as only deregulation of HERV-W and HERV-K (HML-6) was found in these cell cultures after their infection with HIV. Multiple factors contribute to this aberrant HERV expression, and its levels appear to be modified in a time-dependent manner. Further studies and the development of optimized in vitro protocols are warranted to elucidate the interactions between HIV and HERVs in detail.
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Affiliation(s)
- Federica Mantovani
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Konstantina Kitsou
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Dimitrios Paraskevis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Pagona Lagiou
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Gkikas Magiorkinis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Athens, Greece
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Liu M, Jia L, Guo X, Zhai X, Li H, Liu Y, Han J, Zhang B, Wang X, Li T, Wang Y, Li J, Yu C, Li L. Identification and Characterization of the HERV-K (HML-8) Group of Human Endogenous Retroviruses in the Genome. AIDS Res Hum Retroviruses 2023; 39:176-194. [PMID: 36656667 DOI: 10.1089/aid.2022.0084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Human endogenous retroviruses (HERVs) can be vertically transmitted in a Mendelian fashion, are stably maintained in the human genome, and are estimated to constitute ∼8% of the genome. HERVs affect human physiology and pathology through their provirus-encoded protein or long terminal repeat (LTR) element effect. Characterization of the genomic distribution is an essential step to understanding the relationships between endogenous retrovirus expression and diseases. However, the poor characterization of human MMTV-like (HML)-8 prevents a detailed understanding of the regulation of the expression of this family in humans and its impact on the host genome. In light of this, the definition of an accurate and updated HERV-K HML-8 genomic map is urgently needed. In this study, we report the results of a comprehensive analysis of HERV-K HML-8 sequence presence and distribution within the human genome and hominoids, with a detailed description of the different structural and phylogenetic aspects characterizing the group. A total of 40 proviruses and 5 solo LTR elements for human were characterized, which included a detailed description of provirus structure, integration time, potentially regulated genes, transcription factor-binding sites, and primer-binding site features. Besides, 9 chimpanzee sequences, 8 gorilla sequences, and 10 orangutan sequences belonging to the HML-8 subgroup were identified. The integration time results showed that the HML-8 elements were integrated into the primate lineage around 35 and 42 million years ago (mya), during primates evolutionary speciation. Overall, the results clarified the composition of the HML-8 groups, providing an exhaustive background for subsequent functional studies.
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Affiliation(s)
- Mengying Liu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Lei Jia
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Xing Guo
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China.,Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Xiuli Zhai
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China.,Department of Microbiology, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Hanping Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Yongjian Liu
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Jingwan Han
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Bohan Zhang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Xiaolin Wang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Tianyi Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Yanglan Wang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Jingyun Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
| | - Changyuan Yu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Lin Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing, China
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Specialized DNA Structures Act as Genomic Beacons for Integration by Evolutionarily Diverse Retroviruses. Viruses 2023; 15:v15020465. [PMID: 36851678 PMCID: PMC9962126 DOI: 10.3390/v15020465] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/04/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Retroviral integration site targeting is not random and plays a critical role in expression and long-term survival of the integrated provirus. To better understand the genomic environment surrounding retroviral integration sites, we performed a meta-analysis of previously published integration site data from evolutionarily diverse retroviruses, including new experimental data from HIV-1 subtypes A, B, C and D. We show here that evolutionarily divergent retroviruses exhibit distinct integration site profiles with strong preferences for integration near non-canonical B-form DNA (non-B DNA). We also show that in vivo-derived HIV-1 integration sites are significantly more enriched in transcriptionally silent regions and transcription-silencing non-B DNA features of the genome compared to in vitro-derived HIV-1 integration sites. Integration sites from individuals infected with HIV-1 subtype A, B, C or D viruses exhibited different preferences for common genomic and non-B DNA features. In addition, we identified several integration site hotspots shared between different HIV-1 subtypes, all of which were located in the non-B DNA feature slipped DNA. Together, these data show that although evolutionarily divergent retroviruses exhibit distinct integration site profiles, they all target non-B DNA for integration. These findings provide new insight into how retroviruses integrate into genomes for long-term survival.
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7
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Burn A, Roy F, Freeman M, Coffin JM. Widespread expression of the ancient HERV-K (HML-2) provirus group in normal human tissues. PLoS Biol 2022; 20:e3001826. [PMID: 36256614 PMCID: PMC9578601 DOI: 10.1371/journal.pbio.3001826] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/13/2022] [Indexed: 11/11/2022] Open
Abstract
Human endogenous retrovirus (HERV) transcripts are known to be highly expressed in cancers, yet their activity in nondiseased tissue is largely unknown. Using the GTEx RNA-seq dataset from normal tissue sampled at autopsy, we characterized individual expression of the recent HERV-K (HML-2) provirus group across 13,000 different samples of 54 different tissues from 948 individuals. HML-2 transcripts could be identified in every tissue sampled and were elevated in the cerebellum, pituitary, testis, and thyroid. A total of 37 different individual proviruses were expressed in 1 or more tissues, representing all 3 LTR5 subgroups. Nine proviruses were identified as having long terminal repeat (LTR)-driven transcription, 7 of which belonged to the most recent LTR5HS subgroup. Proviruses of different subgroups displayed a bias in tissue expression, which may be associated with differences in transcription factor binding sites in their LTRs. Provirus expression was greater in evolutionarily older proviruses with an earliest shared ancestor of gorilla or older. HML-2 expression was significantly affected by biological sex in 1 tissue, while age and timing of death (Hardy score) had little effect. Proviruses containing intact gag, pro, and env open reading frames (ORFs) were expressed in the dataset, with almost every tissue measured potentially expressing at least 1 intact ORF (gag). Human endogenous retrovirus (HERV) transcripts are known to be highly expressed in cancers, but what is their activity in normal tissue? This study uses unique patterns of HERV-K RNA expression in the large GEx dataset from non-diseased tissue sites to provide new insights into both the coevolution of HERV-K with our primate ancestors and their current role in human biology.
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Affiliation(s)
- Aidan Burn
- Program in Genetics, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - Farrah Roy
- Immuneering Corporation, Cambridge, Massachusetts, United States of America
| | - Michael Freeman
- Program in Genetics, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - John M. Coffin
- Program in Genetics, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
- Department of Molecular Biology and Microbiology, Tufts University, Boston, Massachusetts, United States of America
- * E-mail:
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8
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Lichterfeld M, Gao C, Yu XG. An ordeal that does not heal: understanding barriers to a cure for HIV-1 infection. Trends Immunol 2022; 43:608-616. [PMID: 35905706 PMCID: PMC9346997 DOI: 10.1016/j.it.2022.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/10/2022] [Accepted: 06/12/2022] [Indexed: 12/23/2022]
Abstract
With more than 38 million people living with HIV-1 (PLWH) worldwide, developing a cure for HIV-1 remains a major global health priority. Lifelong persistence of HIV-1 is frequently attributed to a pool of stable, transcriptionally silent HIV-1 proviruses, which are unaffected by currently available antiretroviral therapy (ART) or host immune activity. In this opinion article, we propose a more dynamic interpretation of HIV-1 reservoir cell biology and argue that HIV-1 proviruses frequently display residual viral transcriptional activity, making them vulnerable to longitudinal immune-mediated selection processes. Such mechanisms may, over extended periods of ART, induce an attenuated viral reservoir profile characterized by intact proviruses preferentially integrated into heterochromatin locations. We suggest that intensifying and accelerating naturally occurring selection mechanisms might represent a promising strategy for finding a potential cure for HIV-1 infection.
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Affiliation(s)
- Mathias Lichterfeld
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA; Infectious Disease Division, Brigham and Women's Hospital, Boston, MA 02115, USA.
| | - Ce Gao
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA; Infectious Disease Division, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Xu G Yu
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA; Infectious Disease Division, Brigham and Women's Hospital, Boston, MA 02115, USA.
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9
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Jia L, Liu M, Yang C, Li H, Liu Y, Han J, Zhai X, Wang X, Li T, Li J, Zhang B, Yu C, Li L. Comprehensive identification and characterization of the HERV-K (HML-9) group in the human genome. Retrovirology 2022; 19:11. [PMID: 35676699 PMCID: PMC9178832 DOI: 10.1186/s12977-022-00596-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/09/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Human endogenous retroviruses (HERVs) result from ancestral infections caused by exogenous retroviruses that became incorporated into the germline DNA and evolutionarily fixed in the human genome. HERVs can be transmitted vertically in a Mendelian fashion and be stably maintained in the human genome, of which they are estimated to comprise approximately 8%. HERV-K (HML1-10) transcription has been confirmed to be associated with a variety of diseases, such as breast cancer, lung cancer, prostate cancer, melanoma, rheumatoid arthritis, and amyotrophic lateral sclerosis. However, the poor characterization of HML-9 prevents a detailed understanding of the regulation of the expression of this family in humans and its impact on the host genome. In light of this, a precise and updated HERV-K HML-9 genomic map is urgently needed to better evaluate the role of these elements in human health. RESULTS We report a comprehensive analysis of the presence and distribution of HERV-K HML-9 elements within the human genome, with a detailed characterization of the structural and phylogenetic properties of the group. A total of 23 proviruses and 47 solo LTR elements were characterized, with a detailed description of the provirus structure, integration time, potential regulated genes, transcription factor binding sites (TFBS), and primer binding site (PBS) features. The integration time results showed that the HML-9 elements found in the human genome integrated into the primate lineage between 17.5 and 48.5 million years ago (mya). CONCLUSION The results provide a clear characterization of HML-9 and a comprehensive background for subsequent functional studies.
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Affiliation(s)
- Lei Jia
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Mengying Liu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 China
| | - Caiqin Yang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Hanping Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Yongjian Liu
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Jingwan Han
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Xiuli Zhai
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Xiaolin Wang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Tianyi Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Jingyun Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Bohan Zhang
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
| | - Changyuan Yu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029 China
| | - Lin Li
- Department of Virology, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071 China
- State Key Laboratory of Pathogen and Biosecurity, Beijing, 100071 China
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10
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Bakoulis S, Krautz R, Alcaraz N, Salvatore M, Andersson R. OUP accepted manuscript. Nucleic Acids Res 2022; 50:2111-2127. [PMID: 35166831 PMCID: PMC8887488 DOI: 10.1093/nar/gkac088] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 01/22/2022] [Accepted: 01/27/2022] [Indexed: 11/12/2022] Open
Affiliation(s)
| | | | - Nicolas Alcaraz
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research (CPR), University of Copenhagen, 2200 Copenhagen, Denmark
| | - Marco Salvatore
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Robin Andersson
- To whom correspondence should be addressed. Tel: +45 35330245;
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11
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Zheng J, Wei Y, Han GZ. The diversity and evolution of retroviruses: perspectives from viral “fossils”. Virol Sin 2022; 37:11-18. [PMID: 35234634 PMCID: PMC8922424 DOI: 10.1016/j.virs.2022.01.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 10/12/2021] [Indexed: 01/19/2023] Open
Abstract
Retroviruses exclusively infect vertebrates, causing a variety of diseases. The replication of retroviruses requires reverse transcription and integration into host genomes. When infecting germline cells, retroviruses become inherited vertically, forming endogenous retroviruses (ERVs). ERVs document past viral infections, providing molecular fossils for studying the evolutionary history of retroviruses. In this review, we summarize the recent advances in understanding the diversity and evolution of retroviruses from the perspectives of viral fossils, and discuss the effects of ERVs on the evolution of host biology. Recent advances in understanding the diversity and evolution of retroviruses. Methods to analyze ERVs. The effects of ERVs on the evolution of host biology.
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Affiliation(s)
- Jialu Zheng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Yutong Wei
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Guan-Zhu Han
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China.
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12
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Jansz N, Faulkner GJ. Endogenous retroviruses in the origins and treatment of cancer. Genome Biol 2021; 22:147. [PMID: 33971937 PMCID: PMC8108463 DOI: 10.1186/s13059-021-02357-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/21/2021] [Indexed: 02/07/2023] Open
Abstract
Endogenous retroviruses (ERVs) are emerging as promising therapeutic targets in cancer. As remnants of ancient retroviral infections, ERV-derived regulatory elements coordinate expression from gene networks, including those underpinning embryogenesis and immune cell function. ERV activation can promote an interferon response, a phenomenon termed viral mimicry. Although ERV expression is associated with cancer, and provisionally with autoimmune and neurodegenerative diseases, ERV-mediated inflammation is being explored as a way to sensitize tumors to immunotherapy. Here we review ERV co-option in development and innate immunity, the aberrant contribution of ERVs to tumorigenesis, and the wider biomedical potential of therapies directed at ERVs.
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Affiliation(s)
- Natasha Jansz
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, QLD, 4102, Australia.
| | - Geoffrey J Faulkner
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, QLD, 4102, Australia. .,Queensland Brain Institute, University of Queensland, Brisbane, QLD, 4072, Australia.
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13
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Abstract
Retroviruses infect a broad range of vertebrate hosts that includes amphibians, reptiles, fish, birds and mammals. In addition, a typical vertebrate genome contains thousands of loci composed of ancient retroviral sequences known as endogenous retroviruses (ERVs). ERVs are molecular remnants of ancient retroviruses and proof that the ongoing relationship between retroviruses and their vertebrate hosts began hundreds of millions of years ago. The long-term impact of retroviruses on vertebrate evolution is twofold: first, as with other viruses, retroviruses act as agents of selection, driving the evolution of host genes that block viral infection or that mitigate pathogenesis, and second, through the phenomenon of endogenization, retroviruses contribute an abundance of genetic novelty to host genomes, including unique protein-coding genes and cis-acting regulatory elements. This Review describes ERV origins, their diversity and their relationships to retroviruses and discusses the potential for ERVs to reveal virus-host interactions on evolutionary timescales. It also describes some of the many examples of cellular functions, including protein-coding genes and regulatory elements, that have evolved from ERVs.
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14
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The emerging role of epigenetic therapeutics in immuno-oncology. Nat Rev Clin Oncol 2019; 17:75-90. [PMID: 31548600 DOI: 10.1038/s41571-019-0266-5] [Citation(s) in RCA: 252] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2019] [Indexed: 02/07/2023]
Abstract
The past decade has seen the emergence of immunotherapy as a prime approach to cancer treatment, revolutionizing the management of many types of cancer. Despite the promise of immunotherapy, most patients do not have a response or become resistant to treatment. Thus, identifying combinations that potentiate current immunotherapeutic approaches will be crucial. The combination of immune-checkpoint inhibition with epigenetic therapy is one such strategy that is being tested in clinical trials, encompassing a variety of cancer types. Studies have revealed key roles of epigenetic processes in regulating immune cell function and mediating antitumour immunity. These interactions make combined epigenetic therapy and immunotherapy an attractive approach to circumvent the limitations of immunotherapy alone. In this Review, we highlight the basic dynamic mechanisms underlying the synergy between immunotherapy and epigenetic therapies and detail current efforts to translate this knowledge into clinical benefit for patients.
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15
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Spatially clustered loci with multiple enhancers are frequent targets of HIV-1 integration. Nat Commun 2019; 10:4059. [PMID: 31492853 PMCID: PMC6731298 DOI: 10.1038/s41467-019-12046-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/19/2019] [Indexed: 02/06/2023] Open
Abstract
HIV-1 recurrently targets active genes and integrates in the proximity of the nuclear pore compartment in CD4+ T cells. However, the genomic features of these genes and the relevance of their transcriptional activity for HIV-1 integration have so far remained unclear. Here we show that recurrently targeted genes are proximal to super-enhancer genomic elements and that they cluster in specific spatial compartments of the T cell nucleus. We further show that these gene clusters acquire their location during the activation of T cells. The clustering of these genes along with their transcriptional activity are the major determinants of HIV-1 integration in T cells. Our results provide evidence of the relevance of the spatial compartmentalization of the genome for HIV-1 integration, thus further strengthening the role of nuclear architecture in viral infection.
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16
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Aiewsakun P, Simmonds P, Katzourakis A. The First Co-Opted Endogenous Foamy Viruses and the Evolutionary History of Reptilian Foamy Viruses. Viruses 2019; 11:v11070641. [PMID: 31336856 PMCID: PMC6669660 DOI: 10.3390/v11070641] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 07/01/2019] [Accepted: 07/04/2019] [Indexed: 12/17/2022] Open
Abstract
A recent study reported the discovery of an endogenous reptilian foamy virus (FV), termed ERV-Spuma-Spu, found in the genome of tuatara. Here, we report two novel reptilian foamy viruses also identified as endogenous FVs (EFVs) in the genomes of panther gecko (ERV-Spuma-Ppi) and Schlegel’s Japanese gecko (ERV-Spuma-Gja). Their presence indicates that FVs are capable of infecting reptiles in addition to mammals, amphibians, and fish. Numerous copies of full length ERV-Spuma-Spu elements were found in the tuatara genome littered with in-frame stop codons and transposable elements, suggesting that they are indeed endogenous and are not functional. ERV-Spuma-Ppi and ERV-Spuma-Gja, on the other hand, consist solely of a foamy virus-like env gene. Examination of host flanking sequences revealed that they are orthologous, and despite being more than 96 million years old, their env reading frames are fully coding competent with evidence for strong purifying selection to maintain expression and for them likely being transcriptionally active. These make them the oldest EFVs discovered thus far and the first documented EFVs that may have been co-opted for potential cellular functions. Phylogenetic analyses revealed a complex virus–host co-evolutionary history and cross-species transmission routes of ancient FVs.
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Affiliation(s)
- Pakorn Aiewsakun
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
| | - Peter Simmonds
- Nuffield Department of Medicine, University of Oxford, South Parks Road, Oxford OX1 3SY, UK
| | - Aris Katzourakis
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3SY, UK.
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17
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Gene therapy targeting haematopoietic stem cells for inherited diseases: progress and challenges. Nat Rev Drug Discov 2019; 18:447-462. [DOI: 10.1038/s41573-019-0020-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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18
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Einkauf KB, Lee GQ, Gao C, Sharaf R, Sun X, Hua S, Chen SM, Jiang C, Lian X, Chowdhury FZ, Rosenberg ES, Chun TW, Li JZ, Yu XG, Lichterfeld M. Intact HIV-1 proviruses accumulate at distinct chromosomal positions during prolonged antiretroviral therapy. J Clin Invest 2019; 129:988-998. [PMID: 30688658 DOI: 10.1172/jci124291] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 12/04/2018] [Indexed: 12/16/2022] Open
Abstract
Chromosomal integration of genome-intact HIV-1 sequences into the host genome creates a reservoir of virally infected cells that persists throughout life, necessitating indefinite antiretroviral suppression therapy. During effective antiviral treatment, the majority of these proviruses remain transcriptionally silent, but mechanisms responsible for viral latency are insufficiently clear. Here, we used matched integration site and proviral sequencing (MIP-Seq), an experimental approach involving multiple displacement amplification of individual proviral species, followed by near-full-length HIV-1 next-generation sequencing and corresponding chromosomal integration site analysis to selectively map the chromosomal positions of intact and defective proviruses in 3 HIV-1-infected individuals undergoing long-term antiretroviral therapy. Simultaneously, chromatin accessibility and gene expression in autologous CD4+ T cells were analyzed by assays for transposase-accessible chromatin using sequencing (ATAC-Seq) and RNA-Seq. We observed that in comparison to proviruses with defective sequences, intact HIV-1 proviruses were enriched for non-genic chromosomal positions and more frequently showed an opposite orientation relative to host genes. In addition, intact HIV-1 proviruses were preferentially integrated in either relative proximity to or increased distance from active transcriptional start sites and to accessible chromatin regions. These studies strongly suggest selection of intact proviruses with features of deeper viral latency during prolonged antiretroviral therapy, and may be informative for targeting the genome-intact viral reservoir.
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Affiliation(s)
- Kevin B Einkauf
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Guinevere Q Lee
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Ce Gao
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Radwa Sharaf
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Xiaoming Sun
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Stephane Hua
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Samantha My Chen
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Chenyang Jiang
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Xiaodong Lian
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - Eric S Rosenberg
- Infectious Disease Division, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Tae-Wook Chun
- National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Maryland, USA
| | - Jonathan Z Li
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Xu G Yu
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Mathias Lichterfeld
- Infectious Disease Division, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
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19
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Garcia-Montojo M, Doucet-O'Hare T, Henderson L, Nath A. Human endogenous retrovirus-K (HML-2): a comprehensive review. Crit Rev Microbiol 2018; 44:715-738. [PMID: 30318978 DOI: 10.1080/1040841x.2018.1501345] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The human genome contains a large number of retroviral elements acquired over the process of evolution, some of which are specific to primates. However, as many of these are defective or silenced through epigenetic changes, they were historically considered "junk DNA" and their potential role in human physiology or pathological circumstances have been poorly studied. The most recently acquired, human endogenous retrovirus-K (HERV-K), has multiple copies in the human genome and some of them have complete open reading frames that are transcribed and translated, especially in early embryogenesis. Phylogenetically, HERV-K is considered a supergroup of viruses. One of the subtypes, termed HML-2, seems to be the most active and hence, it is the best studied. Aberrant expression of HML-2 in adult tissues has been associated with certain types of cancer and with neurodegenerative diseases. This review discusses the discovery of these viruses, their classification, structure, regulation and potential for replication, physiological roles, and their involvement in disease pathogenesis. Finally, it presents different therapeutic approaches being considered to target these viruses.
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Affiliation(s)
- Marta Garcia-Montojo
- a Section of Infections of the Nervous System , National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda , MD , USA
| | - Tara Doucet-O'Hare
- a Section of Infections of the Nervous System , National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda , MD , USA
| | - Lisa Henderson
- a Section of Infections of the Nervous System , National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda , MD , USA
| | - Avindra Nath
- a Section of Infections of the Nervous System , National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda , MD , USA
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20
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Human Endogenous Retrovirus-K HML-2 integration within RASGRF2 is associated with intravenous drug abuse and modulates transcription in a cell-line model. Proc Natl Acad Sci U S A 2018; 115:10434-10439. [PMID: 30249655 DOI: 10.1073/pnas.1811940115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HERV-K HML-2 (HK2) has been proliferating in the germ line of humans at least as recently as 250,000 years ago, with some integrations that remain polymorphic in the modern human population. One of the solitary HK2 LTR polymorphic integrations lies between exons 17 and 18 of RASGRF2, a gene that affects dopaminergic activity and is thus related to addiction. Here we show that this antisense HK2 integration (namely RASGRF2-int) is found more frequently in persons who inject drugs compared with the general population. In a Greek HIV-1-positive population (n = 202), we found RASGRF2-int 2.5 times (14 versus 6%) more frequently in patients infected through i.v. drug use compared with other transmission route controls (P = 0.03). Independently, in a United Kingdom-based hepatitis C virus-positive population (n = 184), we found RASGRF2-int 3.6 times (34 versus 9.5%) more frequently in patients infected during chronic drug abuse compared with controls (P < 0.001). We then tested whether RASGRF2-int could be mechanistically responsible for this association by modulating transcription of RASGRF2 We show that the CRISPR/Cas9-mediated insertion of HK2 in HEK293 cells in the exact RASGRF2 intronic position found in the population resulted in significant transcriptional and phenotypic changes. We also explored mechanistic features of other intronic HK2 integrations and show that HK2 LTRs can be responsible for generation of cis-natural antisense transcripts, which could interfere with the transcription of nearby genes. Our findings suggest that RASGRF2-int is a strong candidate for dopaminergic manipulation, and emphasize the importance of accurate mapping of neglected HERV polymorphisms in human genomic studies.
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21
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Gifford RJ, Blomberg J, Coffin JM, Fan H, Heidmann T, Mayer J, Stoye J, Tristem M, Johnson WE. Nomenclature for endogenous retrovirus (ERV) loci. Retrovirology 2018; 15:59. [PMID: 30153831 PMCID: PMC6114882 DOI: 10.1186/s12977-018-0442-1] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 08/20/2018] [Indexed: 11/10/2022] Open
Abstract
Retroviral integration into germline DNA can result in the formation of a vertically inherited proviral sequence called an endogenous retrovirus (ERV). Over the course of their evolution, vertebrate genomes have accumulated many thousands of ERV loci. These sequences provide useful retrospective information about ancient retroviruses, and have also played an important role in shaping the evolution of vertebrate genomes. There is an immediate need for a unified system of nomenclature for ERV loci, not only to assist genome annotation, but also to facilitate research on ERVs and their impact on genome biology and evolution. In this review, we examine how ERV nomenclatures have developed, and consider the possibilities for the implementation of a systematic approach for naming ERV loci. We propose that such a nomenclature should not only provide unique identifiers for individual loci, but also denote orthologous relationships between ERVs in different species. In addition, we propose that-where possible-mnemonic links to previous, well-established names for ERV loci and groups should be retained. We show how this approach can be applied and integrated into existing taxonomic and nomenclature schemes for retroviruses, ERVs and transposable elements.
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Affiliation(s)
- Robert J Gifford
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK.
| | - Jonas Blomberg
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - John M Coffin
- Department of Molecular Biology and Microbiology, Tufts University, Boston, MA, USA
| | - Hung Fan
- Department of Molecular Biology and Biochemistry and Cancer Research Institute, University of California, Irvine, CA, 92697, USA
| | - Thierry Heidmann
- Department of Molecular Physiology and Pathology of Infectious and Endogenous Retroviruses, CNRS UMR 9196, Institut Gustave Roussy, 94805, Villejuif, France
| | - Jens Mayer
- Department of Human Genetics, Center of Human and Molecular Biology, Medical Faculty, University of Saarland, Homburg, Germany
| | - Jonathan Stoye
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London, UK
| | - Michael Tristem
- Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK
| | - Welkin E Johnson
- Biology Department, Boston College, Chestnut Hill, Massachusetts, 02467, USA.
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22
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Fraietta JA, Nobles CL, Sammons MA, Lundh S, Carty SA, Reich TJ, Cogdill AP, Morrissette JJD, DeNizio JE, Reddy S, Hwang Y, Gohil M, Kulikovskaya I, Nazimuddin F, Gupta M, Chen F, Everett JK, Alexander KA, Lin-Shiao E, Gee MH, Liu X, Young RM, Ambrose D, Wang Y, Xu J, Jordan MS, Marcucci KT, Levine BL, Garcia KC, Zhao Y, Kalos M, Porter DL, Kohli RM, Lacey SF, Berger SL, Bushman FD, June CH, Melenhorst JJ. Disruption of TET2 promotes the therapeutic efficacy of CD19-targeted T cells. Nature 2018; 558:307-312. [PMID: 29849141 DOI: 10.1038/s41586-018-0178-z] [Citation(s) in RCA: 557] [Impact Index Per Article: 92.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 04/27/2018] [Indexed: 12/18/2022]
Abstract
Cancer immunotherapy based on genetically redirecting T cells has been used successfully to treat B cell malignancies1-3. In this strategy, the T cell genome is modified by integration of viral vectors or transposons encoding chimaeric antigen receptors (CARs) that direct tumour cell killing. However, this approach is often limited by the extent of expansion and persistence of CAR T cells4,5. Here we report mechanistic insights from studies of a patient with chronic lymphocytic leukaemia treated with CAR T cells targeting the CD19 protein. Following infusion of CAR T cells, anti-tumour activity was evident in the peripheral blood, lymph nodes and bone marrow; this activity was accompanied by complete remission. Unexpectedly, at the peak of the response, 94% of CAR T cells originated from a single clone in which lentiviral vector-mediated insertion of the CAR transgene disrupted the methylcytosine dioxygenase TET2 gene. Further analysis revealed a hypomorphic mutation in this patient's second TET2 allele. TET2-disrupted CAR T cells exhibited an epigenetic profile consistent with altered T cell differentiation and, at the peak of expansion, displayed a central memory phenotype. Experimental knockdown of TET2 recapitulated the potency-enhancing effect of TET2 dysfunction in this patient's CAR T cells. These findings suggest that the progeny of a single CAR T cell induced leukaemia remission and that TET2 modification may be useful for improving immunotherapies.
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Affiliation(s)
- Joseph A Fraietta
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Parker Institute for Cancer Immunotherapy, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher L Nobles
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Morgan A Sammons
- Department of Cell and Developmental Biology, Epigenetics Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Biology, University at Albany, State University of New York, Albany, NY, USA
| | - Stefan Lundh
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Shannon A Carty
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Internal Medicine and Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA
| | - Tyler J Reich
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexandria P Cogdill
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jennifer J D Morrissette
- Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jamie E DeNizio
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Shantan Reddy
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Young Hwang
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Mercy Gohil
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Irina Kulikovskaya
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Farzana Nazimuddin
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Minnal Gupta
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Fang Chen
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John K Everett
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katherine A Alexander
- Department of Cell and Developmental Biology, Epigenetics Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Enrique Lin-Shiao
- Department of Cell and Developmental Biology, Epigenetics Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marvin H Gee
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Xiaojun Liu
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Regina M Young
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David Ambrose
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yan Wang
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jun Xu
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Martha S Jordan
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katherine T Marcucci
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Bruce L Levine
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - K Christopher Garcia
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yangbing Zhao
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael Kalos
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David L Porter
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rahul M Kohli
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Simon F Lacey
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Shelley L Berger
- Department of Cell and Developmental Biology, Epigenetics Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Frederic D Bushman
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Carl H June
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Parker Institute for Cancer Immunotherapy, University of Pennsylvania, Philadelphia, PA, USA.
| | - J Joseph Melenhorst
- Center for Cellular Immunotherapies, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. .,Parker Institute for Cancer Immunotherapy, University of Pennsylvania, Philadelphia, PA, USA.
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23
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Blanco-Melo D, Gifford RJ, Bieniasz PD. Reconstruction of a replication-competent ancestral murine endogenous retrovirus-L. Retrovirology 2018; 15:34. [PMID: 29716624 PMCID: PMC5930517 DOI: 10.1186/s12977-018-0416-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 04/10/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND About 10% of the mouse genome is composed of endogenous retroviruses (ERVs) that represent a molecular fossil record of past retroviral infections. One such retrovirus, murine ERV-L (MuERV-L) is an env-deficient ERV that has undergone episodic proliferation, with the most recent amplification occurring ~ 2 million years ago. MuERV-L related sequences have been co-opted by mice for antiretroviral defense, and possibly as promoters for some genes that regulate totipotency in early mouse embryos. However, MuERV-L sequences present in modern mouse genomes have not been observed to replicate. RESULTS Here, we describe the reconstruction of an ancestral MuERV-L (ancML) sequence through paleovirological analyses of MuERV-L elements in the modern mouse genome. The resulting MuERV-L (ancML) sequence was synthesized and a reporter gene embedded. The reconstructed MuERV-L (ancML) could replicate in a manner that is dependent on reverse transcription and generated de novo integrants. Notably, MuERV-L (ancML) exhibited a narrow host range. Interferon-α could reduce MuERV-L (ancML) replication, suggesting the existence of interferon-inducible genes that could inhibit MuERV-L replication. While mouse APOBEC3 was able to restrict the replication of MuERV-L (ancML), inspection of endogenous MuERV-L sequences suggested that the impact of APOBEC3 mediated hypermutation on MuERV-L has been minimal. CONCLUSION The reconstruction of an ancestral MuERV-L sequence highlights the potential for the retroviral fossil record to illuminate ancient events and enable studies of the impact of retroviral elements on animal evolution.
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Affiliation(s)
- Daniel Blanco-Melo
- Laboratory of Retrovirology and Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Robert J Gifford
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Paul D Bieniasz
- Laboratory of Retrovirology and Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA.
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24
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Hurst TP, Magiorkinis G. Epigenetic Control of Human Endogenous Retrovirus Expression: Focus on Regulation of Long-Terminal Repeats (LTRs). Viruses 2017; 9:v9060130. [PMID: 28561791 PMCID: PMC5490807 DOI: 10.3390/v9060130] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/22/2017] [Accepted: 05/22/2017] [Indexed: 12/25/2022] Open
Abstract
Transposable elements, including endogenous retroviruses (ERVs), comprise almost 45% of the human genome. This could represent a significant pathogenic burden but it is becoming more evident that many of these elements have a positive contribution to make to normal human physiology. In particular, the contributions of human ERVs (HERVs) to gene regulation and the expression of noncoding RNAs has been revealed with the help of new and emerging genomic technologies. HERVs have the common provirus structure of coding open reading frames (ORFs) flanked by two long-terminal repeats (LTRs). However, over the course of evolution and as a consequence of host defence mechanisms, most of the sequences contain INDELs, mutations or have been reduced to single LTRs by recombination. These INDELs and mutations reduce HERV activity. However, there is a trade-off for the host cells in that HERVs can provide beneficial sources of genetic variation but with this benefit comes the risk of pathogenic activity and spread within the genome. For example, the LTRs are of critical importance as they contain promoter sequences and can regulate not only HERV expression but that of human genes. This is true even when the LTRs are located in intergenic regions or are in antisense orientation to the rest of the gene. Uncontrolled, this promoter activity could disrupt normal gene expression or transcript processing (e.g., splicing). Thus, control of HERVs and particularly their LTRs is essential for the cell to manage these elements and this control is achieved at multiple levels, including epigenetic regulations that permit HERV expression in the germline but silence it in most somatic tissues. We will discuss some of the common epigenetic mechanisms and how they affect HERV expression, providing detailed discussions of HERVs in stem cell, placenta and cancer biology.
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Affiliation(s)
- Tara P Hurst
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
| | - Gkikas Magiorkinis
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece.
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25
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El Ashkar S, Van Looveren D, Schenk F, Vranckx LS, Demeulemeester J, De Rijck J, Debyser Z, Modlich U, Gijsbers R. Engineering Next-Generation BET-Independent MLV Vectors for Safer Gene Therapy. MOLECULAR THERAPY-NUCLEIC ACIDS 2017. [PMID: 28624199 PMCID: PMC5415309 DOI: 10.1016/j.omtn.2017.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Retroviral vectors have shown their curative potential in clinical trials correcting monogenetic disorders. However, therapeutic benefits were compromised due to vector-induced dysregulation of cellular genes and leukemia development in a subset of patients. Bromodomain and extraterminal domain (BET) proteins act as cellular cofactors that tether the murine leukemia virus (MLV) pre-integration complex to host chromatin via interaction with the MLV integrase (IN) and thereby define the typical gammaretroviral integration distribution. We engineered next-generation BET-independent (Bin) MLV vectors to retarget their integration to regions where they are less likely to dysregulate nearby genes. We mutated MLV IN to uncouple BET protein interaction and fused it with chromatin-binding peptides. The addition of the CBX1 chromodomain to MLV INW390A efficiently targeted integration away from gene regulatory elements. The retargeted vector produced at high titers and efficiently transduced CD34+ hematopoietic stem cells, while fewer colonies were detected in a serial colony-forming assay, a surrogate test for genotoxicity. Our findings underscore the potential of the engineered vectors to reduce the risk of insertional mutagenesis without compromising transduction efficiency. Ultimately, combined with other safety features in vector design, next-generation BinMLV vectors can improve the safety of gammaretroviral vectors for gene therapy.
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Affiliation(s)
- Sara El Ashkar
- Laboratory for Molecular Virology and Drug Discovery, Department of Pharmaceutical and Pharmacological Sciences, 3000 Leuven, KU Leuven, Belgium
| | - Dominique Van Looveren
- Laboratory for Viral Vector Technology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Franziska Schenk
- RG Gene Modification in Stem Cells, LOEWE Center for Cell and Gene Therapy Frankfurt, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Lenard S Vranckx
- Laboratory for Molecular Virology and Drug Discovery, Department of Pharmaceutical and Pharmacological Sciences, 3000 Leuven, KU Leuven, Belgium
| | - Jonas Demeulemeester
- Laboratory for Molecular Virology and Drug Discovery, Department of Pharmaceutical and Pharmacological Sciences, 3000 Leuven, KU Leuven, Belgium
| | - Jan De Rijck
- Laboratory for Molecular Virology and Drug Discovery, Department of Pharmaceutical and Pharmacological Sciences, 3000 Leuven, KU Leuven, Belgium
| | - Zeger Debyser
- Laboratory for Molecular Virology and Drug Discovery, Department of Pharmaceutical and Pharmacological Sciences, 3000 Leuven, KU Leuven, Belgium
| | - Ute Modlich
- RG Gene Modification in Stem Cells, LOEWE Center for Cell and Gene Therapy Frankfurt, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Rik Gijsbers
- Laboratory for Viral Vector Technology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium; Leuven Viral Vector Core, KU Leuven, 3000 Leuven, Belgium.
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26
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Integration site selection by retroviruses and transposable elements in eukaryotes. Nat Rev Genet 2017; 18:292-308. [PMID: 28286338 DOI: 10.1038/nrg.2017.7] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Transposable elements and retroviruses are found in most genomes, can be pathogenic and are widely used as gene-delivery and functional genomics tools. Exploring whether these genetic elements target specific genomic sites for integration and how this preference is achieved is crucial to our understanding of genome evolution, somatic genome plasticity in cancer and ageing, host-parasite interactions and genome engineering applications. High-throughput profiling of integration sites by next-generation sequencing, combined with large-scale genomic data mining and cellular or biochemical approaches, has revealed that the insertions are usually non-random. The DNA sequence, chromatin and nuclear context, and cellular proteins cooperate in guiding integration in eukaryotic genomes, leading to a remarkable diversity of insertion site distribution and evolutionary strategies.
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27
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Sherman E, Nobles C, Berry CC, Six E, Wu Y, Dryga A, Malani N, Male F, Reddy S, Bailey A, Bittinger K, Everett JK, Caccavelli L, Drake MJ, Bates P, Hacein-Bey-Abina S, Cavazzana M, Bushman FD. INSPIIRED: A Pipeline for Quantitative Analysis of Sites of New DNA Integration in Cellular Genomes. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 4:39-49. [PMID: 28344990 PMCID: PMC5363316 DOI: 10.1016/j.omtm.2016.11.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/15/2016] [Indexed: 01/24/2023]
Abstract
Integration of new DNA into cellular genomes mediates replication of retroviruses and transposons; integration reactions have also been adapted for use in human gene therapy. Tracking the distributions of integration sites is important to characterize populations of transduced cells and to monitor potential outgrow of pathogenic cell clones. Here, we describe a pipeline for quantitative analysis of integration site distributions named INSPIIRED (integration site pipeline for paired-end reads). We describe optimized biochemical steps for site isolation using Illumina paired-end sequencing, including new technology for suppressing recovery of unwanted contaminants, then software for alignment, quality control, and management of integration site sequences. During library preparation, DNAs are broken by sonication, so that after ligation-mediated PCR the number of ligation junction sites can be used to infer abundance of gene-modified cells. We generated integration sites of known positions in silico, and we describe optimization of sample processing parameters refined by comparison to truth. We also present a novel graph-theory-based method for quantifying integration sites in repeated sequences, and we characterize the consequences using synthetic and experimental data. In an accompanying paper, we describe an additional set of statistical tools for data analysis and visualization. Software is available at https://github.com/BushmanLab/INSPIIRED.
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Affiliation(s)
- Eric Sherman
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Christopher Nobles
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Charles C Berry
- Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emmanuelle Six
- Imagine Institute, Paris Descartes-Sorbonne Paris Cité University, 75014 Paris, France; Laboratory of Human Lymphohematopoiesis, INSERM 24, 75014 Paris, France
| | - Yinghua Wu
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Anatoly Dryga
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Nirav Malani
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Frances Male
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Shantan Reddy
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Aubrey Bailey
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Kyle Bittinger
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - John K Everett
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Laure Caccavelli
- Biotherapy Department, Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris, 75014 Paris, France; Biotherapy Clinical Investigation Center, Groupe Hospitalier Universitaire Ouest, Assistance Publique-Hôpitaux de Paris, INSERM, 75014 Paris, France
| | - Mary J Drake
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Paul Bates
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
| | - Salima Hacein-Bey-Abina
- Biotherapy Department, Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris, 75014 Paris, France; Biotherapy Clinical Investigation Center, Groupe Hospitalier Universitaire Ouest, Assistance Publique-Hôpitaux de Paris, INSERM, 75014 Paris, France
| | - Marina Cavazzana
- Biotherapy Department, Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris, 75014 Paris, France; Biotherapy Clinical Investigation Center, Groupe Hospitalier Universitaire Ouest, Assistance Publique-Hôpitaux de Paris, INSERM, 75014 Paris, France
| | - Frederic D Bushman
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6076, USA
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28
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Broecker F, Horton R, Heinrich J, Franz A, Schweiger MR, Lehrach H, Moelling K. The intron-enriched HERV-K(HML-10) family suppresses apoptosis, an indicator of malignant transformation. Mob DNA 2016; 7:25. [PMID: 27980690 PMCID: PMC5142424 DOI: 10.1186/s13100-016-0081-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/19/2016] [Indexed: 02/06/2023] Open
Abstract
Background Human endogenous retroviruses (HERVs) constitute 8% of the human genome and contribute substantially to the transcriptome. HERVs have been shown to generate RNAs that modulate host gene expression. However, experimental evidence for an impact of these regulatory transcripts on the cellular phenotype has been lacking. Results We characterized the previously little described HERV-K(HML-10) endogenous retrovirus family on a genome-wide scale. HML-10 invaded the ancestral genome of Old World monkeys about 35 Million years ago and is enriched within introns of human genes when compared to other HERV families. We show that long terminal repeats (LTRs) of HML-10 exhibit variable promoter activity in human cancer cell lines. One identified HML-10 LTR-primed RNA was in opposite orientation to the pro-apoptotic Death-associated protein 3 (DAP3). In HeLa cells, experimental inactivation of HML-10 LTR-primed transcripts induced DAP3 expression levels, which led to apoptosis. Conclusions Its enrichment within introns suggests that HML-10 may have been evolutionary co-opted for gene regulation more than other HERV families. We demonstrated such a regulatory activity for an HML-10 RNA that suppressed DAP3-mediated apoptosis in HeLa cells. Since HML-10 RNA appears to be upregulated in various tumor cell lines and primary tumor samples, it may contribute to evasion of apoptosis in malignant cells. However, the overall weak expression of HML-10 transcripts described here raises the question whether our result described for HeLa represent a rare event in cancer. A possible function in other cells or tissues requires further investigation. Electronic supplementary material The online version of this article (doi:10.1186/s13100-016-0081-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Felix Broecker
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany ; Institute of Medical Microbiology, University of Zurich, Gloriastr. 32, 8006 Zurich, Switzerland ; Current affiliation: Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14424 Potsdam, Germany
| | - Roger Horton
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany
| | - Jochen Heinrich
- Institute of Medical Microbiology, University of Zurich, Gloriastr. 32, 8006 Zurich, Switzerland
| | - Alexandra Franz
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany ; Current affiliation: University of Zurich, Institute of Molecular Life Sciences, Winterthurerstr. 190, 8057 Zurich, Switzerland
| | - Michal-Ruth Schweiger
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany ; Current affiliation: Functional Epigenomics, CCG, Cologne University Hospital, University of Cologne, Weyertal 115b, 50931 Cologne, Germany
| | - Hans Lehrach
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany ; Dahlem Centre for Genome Research and Medical Systems Biology, Fabeckstr. 60-62, 14195 Berlin, Germany
| | - Karin Moelling
- Max Planck Institute for molecular Genetics, Ihnestr. 63-73, 14195 Berlin, Germany ; Institute of Medical Microbiology, University of Zurich, Gloriastr. 32, 8006 Zurich, Switzerland
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29
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Chuong EB, Elde NC, Feschotte C. Regulatory activities of transposable elements: from conflicts to benefits. Nat Rev Genet 2016; 18:71-86. [PMID: 27867194 DOI: 10.1038/nrg.2016.139] [Citation(s) in RCA: 777] [Impact Index Per Article: 97.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Transposable elements (TEs) are a prolific source of tightly regulated, biochemically active non-coding elements, such as transcription factor-binding sites and non-coding RNAs. Many recent studies reinvigorate the idea that these elements are pervasively co-opted for the regulation of host genes. We argue that the inherent genetic properties of TEs and the conflicting relationships with their hosts facilitate their recruitment for regulatory functions in diverse genomes. We review recent findings supporting the long-standing hypothesis that the waves of TE invasions endured by organisms for eons have catalysed the evolution of gene-regulatory networks. We also discuss the challenges of dissecting and interpreting the phenotypic effect of regulatory activities encoded by TEs in health and disease.
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Affiliation(s)
- Edward B Chuong
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84103, USA
| | - Nels C Elde
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84103, USA
| | - Cédric Feschotte
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84103, USA
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30
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Hanke K, Hohn O, Bannert N. HERV-K(HML-2), a seemingly silent subtenant - but still waters run deep. APMIS 2016; 124:67-87. [PMID: 26818263 DOI: 10.1111/apm.12475] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/12/2015] [Indexed: 01/26/2023]
Abstract
A large proportion of the human genome consists of endogenous retroviruses, some of which are well preserved, showing transcriptional activity, and expressing retroviral proteins. The HERV-K(HML-2) family represents the most intact members of these elements, with some having open and intact reading frames for viral proteins and the ability to form virus-like particles. Although generally suppressed in most healthy tissues by a variety of epigenetic processes and antiviral mechanisms, there is evidence that some members of this family are (at least partly) still active - particularly in certain stem cells and various tumors. This raises the possibility of their involvement in tumor induction or in developmental processes. In recent years, many new insights into this fascinating field have been attained, and this review focuses on new discoveries about coevolutionary events and intracellular defense mechanisms against HERV-K(HML-2) activity. We also describe what might occur when these mechanisms fail or become modulated by viral proteins or other viruses and discuss the new vistas opened up by the reconstitution of ancestral viral proteins and even complete HML-2 viruses.
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Affiliation(s)
- Kirsten Hanke
- Department HIV and Other Retroviruses, Robert Koch Institute, Berlin, Germany
| | - Oliver Hohn
- Department HIV and Other Retroviruses, Robert Koch Institute, Berlin, Germany
| | - Norbert Bannert
- Department HIV and Other Retroviruses, Robert Koch Institute, Berlin, Germany
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31
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Campos-Sánchez R, Cremona MA, Pini A, Chiaromonte F, Makova KD. Integration and Fixation Preferences of Human and Mouse Endogenous Retroviruses Uncovered with Functional Data Analysis. PLoS Comput Biol 2016; 12:e1004956. [PMID: 27309962 PMCID: PMC4911145 DOI: 10.1371/journal.pcbi.1004956] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 04/29/2016] [Indexed: 01/24/2023] Open
Abstract
Endogenous retroviruses (ERVs), the remnants of retroviral infections in the germ line, occupy ~8% and ~10% of the human and mouse genomes, respectively, and affect their structure, evolution, and function. Yet we still have a limited understanding of how the genomic landscape influences integration and fixation of ERVs. Here we conducted a genome-wide study of the most recently active ERVs in the human and mouse genome. We investigated 826 fixed and 1,065 in vitro HERV-Ks in human, and 1,624 fixed and 242 polymorphic ETns, as well as 3,964 fixed and 1,986 polymorphic IAPs, in mouse. We quantitated >40 human and mouse genomic features (e.g., non-B DNA structure, recombination rates, and histone modifications) in ±32 kb of these ERVs' integration sites and in control regions, and analyzed them using Functional Data Analysis (FDA) methodology. In one of the first applications of FDA in genomics, we identified genomic scales and locations at which these features display their influence, and how they work in concert, to provide signals essential for integration and fixation of ERVs. The investigation of ERVs of different evolutionary ages (young in vitro and polymorphic ERVs, older fixed ERVs) allowed us to disentangle integration vs. fixation preferences. As a result of these analyses, we built a comprehensive model explaining the uneven distribution of ERVs along the genome. We found that ERVs integrate in late-replicating AT-rich regions with abundant microsatellites, mirror repeats, and repressive histone marks. Regions favoring fixation are depleted of genes and evolutionarily conserved elements, and have low recombination rates, reflecting the effects of purifying selection and ectopic recombination removing ERVs from the genome. In addition to providing these biological insights, our study demonstrates the power of exploiting multiple scales and localization with FDA. These powerful techniques are expected to be applicable to many other genomic investigations.
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Affiliation(s)
- Rebeca Campos-Sánchez
- Genetics Graduate Program, The Huck Institutes of the Life Sciences, Penn State University, University Park, Pennsylvania, United States of America
| | - Marzia A. Cremona
- MOX—Modeling and Scientific Computing, Department of Mathematics, Politecnico di Milano, Milano, Italy
- Department of Statistics, Penn State University, University Park, Pennsylvania, United States of America
| | - Alessia Pini
- MOX—Modeling and Scientific Computing, Department of Mathematics, Politecnico di Milano, Milano, Italy
| | - Francesca Chiaromonte
- Department of Statistics, Penn State University, University Park, Pennsylvania, United States of America
- Center for Medical Genomics, The Huck Institutes of the Life Sciences, Penn State University, University Park, Pennsylvania, United States of America
| | - Kateryna D. Makova
- Center for Medical Genomics, The Huck Institutes of the Life Sciences, Penn State University, University Park, Pennsylvania, United States of America
- Department of Biology, Penn State University, University Park, Pennsylvania, United States of America
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Garcia-Etxebarria K, Jugo BM. Genome-wide reexamination of endogenous retroviruses in Rattus norvegicus. Virology 2016; 494:119-28. [PMID: 27107945 DOI: 10.1016/j.virol.2016.04.006] [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: 10/28/2015] [Revised: 04/02/2016] [Accepted: 04/04/2016] [Indexed: 01/18/2023]
Abstract
Endogenous retroviruses (ERVs) are remnants of retroviral infections that are present in a large number of vertebrate genomes. Based on the proposal that the rat could act as a reservoir of retroviruses, rat ERVs were analysed in silico using a whole-genome approach. To enrich the detected ERV groups, we applied an upgraded approach based on the hidden Markov model. We found 2637 elements that were classified into the following groups: 9 groups of Class I; 15 of Class II, 7 of them previously described; 1 of Class III; and 3 groups whose classification was unclear but were distantly related to Class I. Sixteen ERV groups seemed to be specific to rat. The high number of rat-specific groups might be related to the contact of rats with retroviruses and their role as a reservoir. In addition, the env gene of the more extended groups seemed to be undetectable.
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Affiliation(s)
- Koldo Garcia-Etxebarria
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), 644 Postakutxa, E-48080 Bilbao, Spain
| | - Begoña M Jugo
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), 644 Postakutxa, E-48080 Bilbao, Spain.
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Kim YJ, Ahn K, Gim JA, Oh MH, Han K, Kim HS. Gene structure variation in segmental duplication block C of human chromosome 7q 11.23 during primate evolution. Gene 2015. [PMID: 26196062 DOI: 10.1016/j.gene.2015.07.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Segmental duplication, or low-copy repeat (LCR) event, occurs during primate evolution and is an important source of genomic diversity, including gain or loss of gene function. The human chromosome 7q 11.23 is related to the William-Beuren syndrome and contains large region-specific LCRs composed of blocks A, B, and C that have different copy numbers in humans and different primates. We analyzed the structure of POM121, NSUN5, FKBP6, and TRIM50 genes in the LCRs of block C. Based on computational analysis, POM121B created by a segmental duplication acquired a new exonic region, whereas NSUN5B (NSUN5C) showed structural variation by integration of HERV-K LTR after duplication from the original NSUN5 gene. The TRIM50 gene originally consists of seven exons, whereas the duplicated TRIM73 and TRIM74 genes present five exons because of homologous recombination-mediated deletion. In addition, independent duplication events of the FKBP6 gene generated two pseudogenes at different genomic locations. In summary, these clustered genes are created by segmental duplication, indicating that they show dynamic evolutionary events, leading to structure variation in the primate genome.
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Affiliation(s)
- Yun-Ji Kim
- Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Republic of Korea; DKU-Theragen Institute for NGS Analysis (DTiNa), Cheonan 330-714, Republic of Korea
| | - Kung Ahn
- TBI, Theragen BiO Institute, TheragenEtex, Suwon 443-270, Republic of Korea
| | - Jeong-An Gim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | - Man Hwan Oh
- Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Republic of Korea
| | - Kyudong Han
- Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Republic of Korea; DKU-Theragen Institute for NGS Analysis (DTiNa), Cheonan 330-714, Republic of Korea
| | - Heui-Soo Kim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea.
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Wang T, Birsoy K, Hughes NW, Krupczak KM, Post Y, Wei JJ, Lander ES, Sabatini DM. Identification and characterization of essential genes in the human genome. Science 2015; 350:1096-101. [PMID: 26472758 PMCID: PMC4662922 DOI: 10.1126/science.aac7041] [Citation(s) in RCA: 1104] [Impact Index Per Article: 122.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 10/01/2015] [Indexed: 12/13/2022]
Abstract
Large-scale genetic analysis of lethal phenotypes has elucidated the molecular underpinnings of many biological processes. Using the bacterial clustered regularly interspaced short palindromic repeats (CRISPR) system, we constructed a genome-wide single-guide RNA library to screen for genes required for proliferation and survival in a human cancer cell line. Our screen revealed the set of cell-essential genes, which was validated with an orthogonal gene-trap-based screen and comparison with yeast gene knockouts. This set is enriched for genes that encode components of fundamental pathways, are expressed at high levels, and contain few inactivating polymorphisms in the human population. We also uncovered a large group of uncharacterized genes involved in RNA processing, a number of whose products localize to the nucleolus. Last, screens in additional cell lines showed a high degree of overlap in gene essentiality but also revealed differences specific to each cell line and cancer type that reflect the developmental origin, oncogenic drivers, paralogous gene expression pattern, and chromosomal structure of each line. These results demonstrate the power of CRISPR-based screens and suggest a general strategy for identifying liabilities in cancer cells.
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Affiliation(s)
- Tim Wang
- Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA. Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02139, USA
| | - Kıvanç Birsoy
- Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA. Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02139, USA
| | - Nicholas W Hughes
- Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Kevin M Krupczak
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02139, USA
| | - Yorick Post
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02139, USA
| | - Jenny J Wei
- Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA. Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Eric S Lander
- Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
| | - David M Sabatini
- Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, USA. Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA. David H. Koch Institute for Integrative Cancer Research at MIT, Cambridge, MA 02139, USA. Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Kramer P, Lausch V, Volkwein A, Hanke K, Hohn O, Bannert N. The human endogenous retrovirus K(HML-2) has a broad envelope-mediated cellular tropism and is prone to inhibition at a post-entry, pre-integration step. Virology 2015; 487:121-8. [PMID: 26517399 DOI: 10.1016/j.virol.2015.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/09/2015] [Accepted: 10/14/2015] [Indexed: 11/28/2022]
Abstract
The HERV-K(HML-2) family is the most recent addition to the collection of human endogenous retroviruses. It comprises proviruses that encode functional proteins that can assemble into replication defective particles carrying the envelope protein. Using a reconstituted HERV-K113 envelope sequence, we have analyzed its ability to mediate entry into a set of 33 cell lines from 10 species. Of these, 30 were permissive, demonstrating an amphotropism consistent with a broad expression of receptor protein(s). In an initial effort to identify a receptor for HERV-K(HML-2) we investigated whether transferrin receptor 1 and hyaluronidase 2, known cellular receptors of the closely related betaretroviruses mouse mammary tumor virus (MMTV) and Jaagsiekte sheep retrovirus (JSRV), could facilitate HERV-K(HML-2) entry. However, neither of these proteins could serve as a receptor for HERV-K(HML-2). Moreover, during attempts to further characterize the tropism of HERV-K(HML-2), we identified a cellular activity that inhibits infection at a post-entry, pre-integration step.
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Affiliation(s)
- Philipp Kramer
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany
| | - Veronika Lausch
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany
| | - Alexander Volkwein
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany
| | - Kirsten Hanke
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany
| | - Oliver Hohn
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany
| | - Norbert Bannert
- Robert Koch Institute, Division for HIV and Other Retroviruses, Nordufer 20, 13353 Berlin, Germany.
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Rong Y, Nakamura S, Hirata T, Motooka D, Liu YS, He ZA, Gao XD, Maeda Y, Kinoshita T, Fujita M. Genome-Wide Screening of Genes Required for Glycosylphosphatidylinositol Biosynthesis. PLoS One 2015; 10:e0138553. [PMID: 26383639 PMCID: PMC4575048 DOI: 10.1371/journal.pone.0138553] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/01/2015] [Indexed: 01/16/2023] Open
Abstract
Glycosylphosphatidylinositol (GPI) is synthesized and transferred to proteins in the endoplasmic reticulum (ER). GPI-anchored proteins are then transported from the ER to the plasma membrane through the Golgi apparatus. To date, at least 17 steps have been identified to be required for the GPI biosynthetic pathway. Here, we aimed to establish a comprehensive screening method to identify genes involved in GPI biosynthesis using mammalian haploid screens. Human haploid cells were mutagenized by the integration of gene trap vectors into the genome. Mutagenized cells were then treated with a bacterial pore-forming toxin, aerolysin, which binds to GPI-anchored proteins for targeting to the cell membrane. Cells that showed low surface expression of CD59, a GPI-anchored protein, were further enriched for. Gene trap insertion sites in the non-selected population and in the enriched population were determined by deep sequencing. This screening enriched 23 gene regions among the 26 known GPI biosynthetic genes, which when mutated are expected to decrease the surface expression of GPI-anchored proteins. Our results indicate that the forward genetic approach using haploid cells is a useful and powerful technique to identify factors involved in phenotypes of interest.
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Affiliation(s)
- Yao Rong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Shota Nakamura
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Tetsuya Hirata
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565–0871, Japan
- WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Daisuke Motooka
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Yi-Shi Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Zeng-An He
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Xiao-Dong Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, 214122, China
- * E-mail: (XDG); (MF)
| | - Yusuke Maeda
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565–0871, Japan
- WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Taroh Kinoshita
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565–0871, Japan
- WPI Immunology Frontier Research Center, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Morihisa Fujita
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, 214122, China
- * E-mail: (XDG); (MF)
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Sherrill-Mix S, Ocwieja KE, Bushman FD. Gene activity in primary T cells infected with HIV89.6: intron retention and induction of genomic repeats. Retrovirology 2015; 12:79. [PMID: 26377088 PMCID: PMC4574318 DOI: 10.1186/s12977-015-0205-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 08/28/2015] [Indexed: 02/07/2023] Open
Abstract
Background HIV infection has been reported to alter cellular gene activity, but published studies have commonly assayed transformed cell lines and lab-adapted HIV strains, yielding inconsistent results. Here we carried out a deep RNA-Seq analysis of primary human T cells infected with the low passage HIV isolate HIV89.6. Results Seventeen percent of cellular genes showed altered activity 48 h after infection. In a meta-analysis including four other studies, our data differed from studies of HIV infection in cell lines but showed more parallels with infections of primary cells. We found a global trend toward retention of introns after infection, suggestive of a novel cellular response to infection. HIV89.6 infection was also associated with activation of several human endogenous retroviruses (HERVs) and retrotransposons, of interest as possible novel antigens that could serve as vaccine targets. The most highly activated group of HERVs was a subset of the ERV-9. Analysis showed that activation was associated with a particular variant of ERV-9 long terminal repeats that contains an indel near the U3-R border. These data also allowed quantification of >70 splice forms of the HIV89.6 RNA and specified the main types of chimeric HIV89.6-host RNAs. Comparison to over 100,000 integration site sequences from the same infected cell populations allowed quantification of authentic versus artifactual chimeric reads, showing that 5′ read-in, splicing out of HIV89.6 from the D4 donor and 3′ read-through were the most common HIV89.6-host cell chimeric RNA forms. Conclusions Analysis of RNA abundance after infection of primary T cells with the low passage HIV89.6 isolate disclosed multiple novel features of HIV-host interactions, notably intron retention and induction of transcription of retrotransposons and endogenous retroviruses. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0205-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Scott Sherrill-Mix
- Department of Microbiology, Perelman School of Medicine at the University of Pennsylvania, 425 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA, 19104, USA.
| | - Karen E Ocwieja
- Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Frederic D Bushman
- Department of Microbiology, Perelman School of Medicine at the University of Pennsylvania, 425 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA, 19104, USA.
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Abstract
Endogenous retroviruses comprise millions of discrete genetic loci distributed within the genomes of extant vertebrates. These sequences, which are clearly related to exogenous retroviruses, represent retroviral infections of the deep past, and their abundance suggests that retroviruses were a near-constant presence throughout the evolutionary history of modern vertebrates. Endogenous retroviruses contribute in myriad ways to the evolution of host genomes, as mutagens and as sources of genetic novelty (both coding and regulatory) to be acted upon by the twin engines of random genetic drift and natural selection. Importantly, the richness and complexity of endogenous retrovirus data can be used to understand how viruses spread and adapt on evolutionary timescales by combining population genetics and evolutionary theory with a detailed understanding of retrovirus biology (gleaned from the study of extant retroviruses). In addition to revealing the impact of viruses on organismal evolution, such studies can help us better understand, by looking back in time, how life-history traits, as well as ecological and geological events, influence the movement of viruses within and between populations.
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Affiliation(s)
- Welkin E Johnson
- Biology Department, Boston College, Chestnut Hill, Massachusetts 02467;
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Contreras-Galindo R, Kaplan MH, Dube D, Gonzalez-Hernandez MJ, Chan S, Meng F, Dai M, Omenn GS, Gitlin SD, Markovitz DM. Human Endogenous Retrovirus Type K (HERV-K) Particles Package and Transmit HERV-K-Related Sequences. J Virol 2015; 89:7187-201. [PMID: 25926654 PMCID: PMC4473553 DOI: 10.1128/jvi.00544-15] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 04/25/2015] [Indexed: 01/01/2023] Open
Abstract
UNLABELLED Human endogenous retroviruses (HERV) make up 8% of the human genome. While the youngest of these retroviruses, HERV-K(HML-2), termed HK2, is able to code for all viral proteins and produce virus-like particles, it is not known if these virus particles package and transmit HK2-related sequences. Here, we analyzed the capacity of HK2 for packaging and transmitting HK2 sequences. We created an HK2 probe, termed Bogota, which can be packaged into HK2 viruses, and transfected it into cells that make HK2 particles. Supernatants of the transfected cells, which contained HK2 viral particles, then were added to target cells, and the transmissibility of the HK2 Bogota reporter was tracked by G418 resistance. Our studies revealed that contemporary HK2 virions produced by some teratocarcinoma and breast cancer cell lines, as well as by peripheral blood lymphocytes from lymphoma patients, can package HK2 Bogota probes, and these viruses transmitted these probes to other cells. After transmission, HK2 Bogota transcripts undergo reverse transcription, a step impaired by antiretroviral agents or by introduction of mutations into the probe sequences required for reverse transcription. HK2 viruses were more efficiently transmitted in the presence of HK2 Rec or HIV-1 Tat and Vif. Transmitted Bogota probes formed episomes but did not integrate into the cellular genome. Resistance to integration might explain the relatively low number of HK2 insertions that were acquired during the last 25 million years of evolution. Whether transient transmission of modern HK2 sequences, which encode two putative oncoproteins, can lead to disease remains to be studied. IMPORTANCE Retroviruses invaded the genome of human ancestors over the course of millions of years, yet these viruses generally have been inactivated during evolution, with only remnants of these infectious sequences remaining in the human genome. One of these viruses, termed HK2, still is capable of producing virus particles, although these particles have been regarded as being noninfectious. Using a genetic probe derived from HK2, we have discovered that HK2 viruses produced in modern humans can package HK2 sequences and transmit them to various other cells. Furthermore, the genetic sequences packaged in HK2 undergo reverse transcription. The transmitted probe circularized in the cell and failed to integrate into the cellular genome. These findings suggest that modern HK2 viruses can package viral RNA and transmit it to other cells. Contrary to previous views, we provide evidence of an extracellular viral phase of modern HK2 viruses. We have no evidence of sustained, spreading infection.
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Affiliation(s)
| | - Mark H Kaplan
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Derek Dube
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Marta J Gonzalez-Hernandez
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA Programs in Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Susana Chan
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Fan Meng
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, Michigan, USA Department of Psychiatry, University of Michigan, Ann Arbor, Michigan, USA
| | - Manhong Dai
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Gilbert S Omenn
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA Comprehensive Cancer Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Scott D Gitlin
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA Comprehensive Cancer Center, University of Michigan, Ann Arbor, Michigan, USA Veteran Affairs Health System, Ann Arbor, Michigan, USA
| | - David M Markovitz
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA Programs in Immunology, University of Michigan, Ann Arbor, Michigan, USA Programs in Cancer Biology, University of Michigan, Ann Arbor, Michigan, USA Programs in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, USA
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Key determinants of target DNA recognition by retroviral intasomes. Retrovirology 2015; 12:39. [PMID: 25924943 PMCID: PMC4422553 DOI: 10.1186/s12977-015-0167-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 04/20/2015] [Indexed: 12/11/2022] Open
Abstract
Background Retroviral integration favors weakly conserved palindrome sequences at the sites of viral DNA joining and generates a short (4–6 bp) duplication of host DNA flanking the provirus. We previously determined two key parameters that underlie the target DNA preference for prototype foamy virus (PFV) and human immunodeficiency virus type 1 (HIV-1) integration: flexible pyrimidine (Y)/purine (R) dinucleotide steps at the centers of the integration sites, and base contacts with specific integrase residues, such as Ala188 in PFV integrase and Ser119 in HIV-1 integrase. Here we examined the dinucleotide preference profiles of a range of retroviruses and correlated these findings with respect to length of target site duplication (TSD). Results Integration datasets covering six viral genera and the three lengths of TSD were accessed from the literature or generated in this work. All viruses exhibited significant enrichments of flexible YR and/or selection against rigid RY dinucleotide steps at the centers of integration sites, and the magnitude of this enrichment inversely correlated with TSD length. The DNA sequence environments of in vivo-generated HIV-1 and PFV sites were consistent with integration into nucleosomes, however, the local sequence preferences were largely independent of target DNA chromatinization. Integration sites derived from cells infected with the gammaretrovirus reticuloendotheliosis virus strain A (Rev-A), which yields a 5 bp TSD, revealed the targeting of global chromatin features most similar to those of Moloney murine leukemia virus, which yields a 4 bp duplication. In vitro assays revealed that Rev-A integrase interacts with and is catalytically stimulated by cellular bromodomain containing 4 protein. Conclusions Retroviral integrases have likely evolved to bend target DNA to fit scissile phosphodiester bonds into two active sites for integration, and viruses that cut target DNA with a 6 bp stagger may not need to bend DNA as sharply as viruses that cleave with 4 bp or 5 bp staggers. For PFV and HIV-1, the selection of signature bases and central flexibility at sites of integration is largely independent of chromatin structure. Furthermore, global Rev-A integration is likely directed to chromatin features by bromodomain and extraterminal domain proteins. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0167-3) contains supplementary material, which is available to authorized users.
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Hybrid nonviral/viral vector systems for improved piggyBac DNA transposon in vivo delivery. Mol Ther 2015; 23:667-74. [PMID: 25557623 DOI: 10.1038/mt.2014.254] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 12/19/2014] [Indexed: 12/17/2022] Open
Abstract
The DNA transposon piggyBac is a potential therapeutic agent for multiple genetic diseases such as cystic fibrosis (CF). Recombinant piggyBac transposon and transposase are typically codelivered by plasmid transfection; however, plasmid delivery is inefficient in somatic cells in vivo and is a barrier to the therapeutic application of transposon-based vector systems. Here, we investigate the potential for hybrid piggyBac/viral vectors to transduce cells and support transposase-mediated genomic integration of the transposon. We tested both adenovirus (Ad) and adeno-associated virus (AAV) as transposon delivery vehicles. An Ad vector expressing hyperactive insect piggyBac transposase (iPB7) was codelivered. We show transposase-dependent transposition activity and mapped integrations in mammalian cells in vitro and in vivo from each viral vector platform. We also demonstrate efficient and persistent transgene expression following nasal delivery of piggyBac/viral vectors to mice. Furthermore, using piggyBac/Ad expressing Cystic Fibrosis transmembrane Conductance Regulator (CFTR), we show persistent correction of chloride current in well-differentiated primary cultures of human airway epithelial cells derived from CF patients. Combining the emerging technologies of DNA transposon-based vectors with well-studied adenoviral and AAV delivery provides new tools for in vivo gene transfer and presents an exciting opportunity to increase the delivery efficiency for therapeutic genes such as CFTR.
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Salmons B, Lawson JS, Günzburg WH. Recent developments linking retroviruses to human breast cancer: infectious agent, enemy within or both? J Gen Virol 2014; 95:2589-2593. [PMID: 25217613 DOI: 10.1099/vir.0.070631-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Evidence is accumulating that one or more beta-retrovirus is associated with human breast cancer. Retroviruses can exist as an infectious (exogenous) virus or as a part of the genetic information of cells due to germline integration (endogenous). An exogenous virus with a genome that is highly homologous to mouse mammary tumour virus is gaining acceptance as possibly being associated with human breast cancer, and recently furnished evidence is discussed in this article, as is the evidence for involvement of an endogenous human beta-retrovirus, HERV-K. Modes of interaction are also reviewed and linkages to the APOBEC3 family are suggested.
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Affiliation(s)
- Brian Salmons
- Austrianova, 20 Biopolis Way, 05-518 Centros, Republic of Singapore 138668
| | - James S Lawson
- School of Public Health, University of New South Wales, Sydney, Australia
| | - Walter H Günzburg
- Institute of Virology, Department of Pathobiology, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria
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Garcia-Etxebarria K, Jugo BM. Genomic environment and digital expression of bovine endogenous retroviruses. Gene 2014; 548:14-21. [DOI: 10.1016/j.gene.2014.06.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 02/08/2014] [Accepted: 06/23/2014] [Indexed: 10/25/2022]
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BET-independent MLV-based Vectors Target Away From Promoters and Regulatory Elements. MOLECULAR THERAPY. NUCLEIC ACIDS 2014; 3:e179. [PMID: 25072693 PMCID: PMC4121521 DOI: 10.1038/mtna.2014.33] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/03/2014] [Indexed: 01/09/2023]
Abstract
Stable integration in the host genome renders murine leukemia virus (MLV)-derived vectors attractive tools for gene therapy. Adverse events in otherwise successful clinical trials caused by proto-oncogene activation due to vector integration hamper their application. MLV and MLV-based vectors integrate near strong enhancers, active promoters, and transcription start sites (TSS) through specific interaction of MLV integrase (IN) with the bromodomain and extra-terminal (BET) family of proteins, accounting for insertional mutagenesis. We identified a BET-interaction motif in the C-terminal tail of MLV IN conserved among gammaretroviruses. By deletion of this motif or a single point mutation (INW390A), BET-independent MLV (BinMLV) were engineered. BinMLV vectors carrying INW390A integrate at wild-type efficiency, with an integration profile that no longer correlates with BET chromatin distribution nor with the traditional markers of MLV integration. In particular, BinMLV vector integration associated less with oncogene TSS compared to the MLV vectors currently used in clinical trials. Together, these findings open perspectives to increase the biosafety of gammaretroviral vectors for gene therapy.
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Abstract
UNLABELLED Human endogenous retrovirus type K (HERV-K) proviruses are scattered throughout the human genome, but as no infectious HERV-K virus has been detected to date, the mechanism by which these viruses replicated and populated the genome remains unresolved. Here, we provide evidence that, in addition to the RNA genomes that canonical retroviruses package, modern HERV-K viruses can contain reverse-transcribed DNA (RT-DNA) genomes. Indeed, reverse transcription of genomic HERV-K RNA into the DNA form is able to occur in three distinct times and locations: (i) in the virus-producing cell prior to viral release, yielding a DNA-containing extracellular virus particle similar to the spumaviruses; (ii) within the extracellular virus particle itself, transitioning from an RNA-containing particle to a DNA-containing particle; and (iii) after entry of the RNA-containing virus into the target cell, similar to canonical retroviruses, such as murine leukemia virus and HIV. Moreover, using a resuscitated HERV-K virus construct, we show that both viruses with RNA genomes and viruses with DNA genomes are capable of infecting target cells. This high level of genomic flexibility historically could have permitted these viruses to replicate in various host cell environments, potentially assisting in their many integration events and resulting in their high prevalence in the human genome. Moreover, the ability of modern HERV-K viruses to proceed through reverse transcription and package RT-DNA genomes suggests a higher level of replication competency than was previously understood, and it may be relevant in HERV-K-associated human diseases. IMPORTANCE Retroviral elements comprise at least 8% of the human genome. Of all the endogenous retroviruses, HERV-K viruses are the most intact and biologically active. While a modern infectious HERV-K has yet to be found, HERV-K activation has been associated with cancers, autoimmune diseases, and HIV-1 infection. Thus, determining how this virus family became such a prevalent member of our genome and what it is capable of in its current form are of the utmost importance. Here, we provide evidence that HERV-K viruses currently found in the human genome are able to proceed through reverse transcription and historically utilized a life cycle with a surprising degree of genomic flexibility in which both RNA- and DNA-containing viruses were capable of mediating infection.
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Sharma A, Slaughter A, Jena N, Feng L, Kessl JJ, Fadel HJ, Malani N, Male F, Wu L, Poeschla E, Bushman FD, Fuchs JR, Kvaratskhelia M. A new class of multimerization selective inhibitors of HIV-1 integrase. PLoS Pathog 2014; 10:e1004171. [PMID: 24874515 PMCID: PMC4038613 DOI: 10.1371/journal.ppat.1004171] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 04/22/2014] [Indexed: 12/20/2022] Open
Abstract
The quinoline-based allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are promising candidates for clinically useful antiviral agents. Studies using these compounds have highlighted the role of IN in both early and late stages of virus replication. However, dissecting the exact mechanism of action of the quinoline-based ALLINIs has been complicated by the multifunctional nature of these inhibitors because they both inhibit IN binding with its cofactor LEDGF/p75 and promote aberrant IN multimerization with similar potencies in vitro. Here we report design of small molecules that allowed us to probe the role of HIV-1 IN multimerization independently from IN-LEDGF/p75 interactions in infected cells. We altered the rigid quinoline moiety in ALLINIs and designed pyridine-based molecules with a rotatable single bond to allow these compounds to bridge between interacting IN subunits optimally and promote oligomerization. The most potent pyridine-based inhibitor, KF116, potently (EC50 of 0.024 µM) blocked HIV-1 replication by inducing aberrant IN multimerization in virus particles, whereas it was not effective when added to target cells. Furthermore, KF116 inhibited the HIV-1 IN variant with the A128T substitution, which confers resistance to the majority of quinoline-based ALLINIs. A genome-wide HIV-1 integration site analysis demonstrated that addition of KF116 to target or producer cells did not affect LEDGF/p75-dependent HIV-1 integration in host chromosomes, indicating that this compound is not detectably inhibiting IN-LEDGF/p75 binding. These findings delineate the significance of correctly ordered IN structure for HIV-1 particle morphogenesis and demonstrate feasibility of exploiting IN multimerization as a therapeutic target. Furthermore, pyridine-based compounds present a novel class of multimerization selective IN inhibitors as investigational probes for HIV-1 molecular biology. The administration of highly active-antiretroviral therapy (HAART) has changed what was once a terminal disease into a manageable chronic infection. The success of HAART is manifested by reduced mortality and morbidity of HIV-1 infected patients. However, evolution of HIV-1 strains resistant to current therapies is a major clinical problem in the fight against AIDS. Therefore, new inhibitors with novel mechanisms of action are needed. One such mechanism is to target multimerization of HIV-1 integrase. In the present study, we report the design of pyridine-based small molecules that contain a rotatable single bond to allow optimal bridging between interacting integrase subunits. As a result, pyridine-based compounds stabilized interacting IN subunits and promoted aberrant, higher order integrase multimerization. The most potent compound, KF116, potently inhibited HIV-1 replication by interfering with proper maturation of HIV-1 particles, whereas KF116 at therapeutically relevant (submicromolar) concentrations had no detectable effects on LEDGF/p75 mediated HIV-1 integration. Our findings highlight HIV-1 integrase multimerization as a plausible therapeutic target and offer a path for designing improved inhibitors for potential clinical use.
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Affiliation(s)
- Amit Sharma
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Alison Slaughter
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Nivedita Jena
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Lei Feng
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Jacques J. Kessl
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Hind J. Fadel
- Department of Molecular Medicine & Division of Infectious Diseases, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Nirav Malani
- Perelman School of Medicine, Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Frances Male
- Perelman School of Medicine, Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Li Wu
- Center for Retrovirus Research and Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, United States of America
| | - Eric Poeschla
- Department of Molecular Medicine & Division of Infectious Diseases, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Frederic D. Bushman
- Perelman School of Medicine, Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - James R. Fuchs
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Mamuka Kvaratskhelia
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail:
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Bushman FD. Engineering the human genome: reflections on the beginning. Hum Gene Ther 2014; 25:395-400. [PMID: 24848314 DOI: 10.1089/hum.2014.2524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Frederic D Bushman
- Department of Microbiology, University of Pennsylvania School of Medicine , Philadelphia, PA 19104-6076
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Aiyer S, Swapna GVT, Malani N, Aramini JM, Schneider WM, Plumb MR, Ghanem M, Larue RC, Sharma A, Studamire B, Kvaratskhelia M, Bushman FD, Montelione GT, Roth MJ. Altering murine leukemia virus integration through disruption of the integrase and BET protein family interaction. Nucleic Acids Res 2014; 42:5917-28. [PMID: 24623816 PMCID: PMC4027182 DOI: 10.1093/nar/gku175] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 02/12/2014] [Accepted: 02/12/2014] [Indexed: 12/17/2022] Open
Abstract
We report alterations to the murine leukemia virus (MLV) integrase (IN) protein that successfully result in decreasing its integration frequency at transcription start sites and CpG islands, thereby reducing the potential for insertional activation. The host bromo and extraterminal (BET) proteins Brd2, 3 and 4 interact with the MLV IN protein primarily through the BET protein ET domain. Using solution NMR, protein interaction studies, and next generation sequencing, we show that the C-terminal tail peptide region of MLV IN is important for the interaction with BET proteins and that disruption of this interaction through truncation mutations affects the global targeting profile of MLV vectors. The use of the unstructured tails of gammaretroviral INs to direct association with complexes at active promoters parallels that used by histones and RNA polymerase II. Viruses bearing MLV IN C-terminal truncations can provide new avenues to improve the safety profile of gammaretroviral vectors for human gene therapy.
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Affiliation(s)
- Sriram Aiyer
- Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers University, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - G V T Swapna
- Center for Advanced Biotechnology and Medicine, Department of Molecular Biology and Biochemistry, and Northeast Structural Genomics Consortium, Rutgers, The State University of New Jersey, 679 Hoes Lane West Piscataway, NJ 08854, USA
| | - Nirav Malani
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
| | - James M Aramini
- Center for Advanced Biotechnology and Medicine, Department of Molecular Biology and Biochemistry, and Northeast Structural Genomics Consortium, Rutgers, The State University of New Jersey, 679 Hoes Lane West Piscataway, NJ 08854, USA
| | - William M Schneider
- Department of Biochemistry, Robert Wood Johnson Medical School, UMDNJ, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - Matthew R Plumb
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, 484 W. 12th Ave., 508 Riffe Building, Columbus, OH 43210, USA
| | - Mustafa Ghanem
- Department of Biology, Brooklyn College, 417 Ingersoll Extension and the Graduate Center of the City University of New York, Brooklyn, NY 11210, USA
| | - Ross C Larue
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, 484 W. 12th Ave., 508 Riffe Building, Columbus, OH 43210, USA
| | - Amit Sharma
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, 484 W. 12th Ave., 508 Riffe Building, Columbus, OH 43210, USA
| | - Barbara Studamire
- Department of Biology, Brooklyn College, 417 Ingersoll Extension and the Graduate Center of the City University of New York, Brooklyn, NY 11210, USA
| | - Mamuka Kvaratskhelia
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, 484 W. 12th Ave., 508 Riffe Building, Columbus, OH 43210, USA
| | - Frederic D Bushman
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Gaetano T Montelione
- Center for Advanced Biotechnology and Medicine, Department of Molecular Biology and Biochemistry, and Northeast Structural Genomics Consortium, Rutgers, The State University of New Jersey, 679 Hoes Lane West Piscataway, NJ 08854, USA Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA
| | - Monica J Roth
- Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers University, 675 Hoes Lane, Piscataway, NJ 08854, USA Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA
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de Jong J, Akhtar W, Badhai J, Rust AG, Rad R, Hilkens J, Berns A, van Lohuizen M, Wessels LFA, de Ridder J. Chromatin landscapes of retroviral and transposon integration profiles. PLoS Genet 2014; 10:e1004250. [PMID: 24721906 PMCID: PMC3983033 DOI: 10.1371/journal.pgen.1004250] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 02/04/2014] [Indexed: 12/16/2022] Open
Abstract
The ability of retroviruses and transposons to insert their genetic material into host DNA makes them widely used tools in molecular biology, cancer research and gene therapy. However, these systems have biases that may strongly affect research outcomes. To address this issue, we generated very large datasets consisting of to unselected integrations in the mouse genome for the Sleeping Beauty (SB) and piggyBac (PB) transposons, and the Mouse Mammary Tumor Virus (MMTV). We analyzed (epi)genomic features to generate bias maps at both local and genome-wide scales. MMTV showed a remarkably uniform distribution of integrations across the genome. More distinct preferences were observed for the two transposons, with PB showing remarkable resemblance to bias profiles of the Murine Leukemia Virus. Furthermore, we present a model where target site selection is directed at multiple scales. At a large scale, target site selection is similar across systems, and defined by domain-oriented features, namely expression of proximal genes, proximity to CpG islands and to genic features, chromatin compaction and replication timing. Notable differences between the systems are mainly observed at smaller scales, and are directed by a diverse range of features. To study the effect of these biases on integration sites occupied under selective pressure, we turned to insertional mutagenesis (IM) screens. In IM screens, putative cancer genes are identified by finding frequently targeted genomic regions, or Common Integration Sites (CISs). Within three recently completed IM screens, we identified 7%–33% putative false positive CISs, which are likely not the result of the oncogenic selection process. Moreover, results indicate that PB, compared to SB, is more suited to tag oncogenes. Retroviruses and transposons are widely used in cancer research and gene therapy. However, these systems show integration biases that may strongly affect results. To address this issue, we generated very large datasets consisting of to unselected integrations for the Sleeping Beauty and piggyBac transposons, and the Mouse Mammary Tumor Virus (MMTV). We analyzed (epi)genomic features to generate bias maps at local and genome-wide scales. MMTV showed a remarkably uniform distribution of integrations across the genome, and a striking similarity was observed between piggyBac and the Murine Leukemia Virus. Moreover, we find that target site selection is directed at multiple scales. At larger scales, it is similar across systems, and directed by a set of domain-oriented features, including chromatin compaction, replication timing, and CpG islands. Notable differences between systems are defined at smaller scales by a diverse range of epigenetic features. As a practical application of our findings, we determined that three recent insertional mutagenesis screens - commonly used for cancer gene discovery - contained 7%–33% putative false positive integration hotspots.
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Affiliation(s)
- Johann de Jong
- Computational Cancer Biology Group, Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
| | - Waseem Akhtar
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Jitendra Badhai
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Alistair G. Rust
- Wellcome Trust Sanger Institute, Genome Campus, Hinxton-Cambridge, United Kingdom
| | - Roland Rad
- Department of Medicine II; Klinikum Rechts der Isar; Technische Universität München, German Cancer Research Center (DKFZ), Heidelberg, & German Cancer Consortium (DKTK), Heidelberg, Germany
| | - John Hilkens
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Anton Berns
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
- Skoltech Center for Stem Cell Research, Skolkovo Institute for Science and Technology, Skolkovo, Odintsovsky, Moscow, Russia
| | - Maarten van Lohuizen
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Lodewyk F. A. Wessels
- Computational Cancer Biology Group, Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Delft Bioinformatics Lab, Faculty of EEMCS, TU Delft, Delft, The Netherlands
- * E-mail: (LFAW); (JdR)
| | - Jeroen de Ridder
- Delft Bioinformatics Lab, Faculty of EEMCS, TU Delft, Delft, The Netherlands
- * E-mail: (LFAW); (JdR)
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50
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Larue RC, Plumb MR, Crowe BL, Shkriabai N, Sharma A, DiFiore J, Malani N, Aiyer SS, Roth MJ, Bushman FD, Foster MP, Kvaratskhelia M. Bimodal high-affinity association of Brd4 with murine leukemia virus integrase and mononucleosomes. Nucleic Acids Res 2014; 42:4868-81. [PMID: 24520112 PMCID: PMC4005663 DOI: 10.1093/nar/gku135] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The importance of understanding the molecular mechanisms of murine leukemia virus (MLV) integration into host chromatin is highlighted by the development of MLV-based vectors for human gene-therapy. We have recently identified BET proteins (Brd2, 3 and 4) as the main cellular binding partners of MLV integrase (IN) and demonstrated their significance for effective MLV integration at transcription start sites. Here we show that recombinant Brd4, a representative of the three BET proteins, establishes complementary high-affinity interactions with MLV IN and mononucleosomes (MNs). Brd4(1–720) but not its N- or C-terminal fragments effectively stimulate MLV IN strand transfer activities in vitro. Mass spectrometry- and NMR-based approaches have enabled us to map key interacting interfaces between the C-terminal domain of BRD4 and the C-terminal tail of MLV IN. Additionally, the N-terminal fragment of Brd4 binds to both DNA and acetylated histone peptides, allowing it to bind tightly to MNs. Comparative analyses of the distributions of various histone marks along chromatin revealed significant positive correlations between H3- and H4-acetylated histones, BET protein-binding sites and MLV-integration sites. Our findings reveal a bimodal mechanism for BET protein-mediated MLV integration into select chromatin locations.
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Affiliation(s)
- Ross C Larue
- Center for Retrovirus Research and College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, USA, Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA and Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ 08854, USA
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