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Zhang X, Celic I, Mitchell H, Stuckert S, Vedula L, Han J. Comprehensive profiling of L1 retrotransposons in mouse. Nucleic Acids Res 2024; 52:5166-5178. [PMID: 38647072 PMCID: PMC11109951 DOI: 10.1093/nar/gkae273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 03/25/2024] [Accepted: 04/06/2024] [Indexed: 04/25/2024] Open
Abstract
L1 elements are retrotransposons currently active in mammals. Although L1s are typically silenced in most normal tissues, elevated L1 expression is associated with a variety of conditions, including cancer, aging, infertility and neurological disease. These associations have raised interest in the mapping of human endogenous de novo L1 insertions, and a variety of methods have been developed for this purpose. Adapting these methods to mouse genomes would allow us to monitor endogenous in vivo L1 activity in controlled, experimental conditions using mouse disease models. Here, we use a modified version of transposon insertion profiling, called nanoTIPseq, to selectively enrich young mouse L1s. By linking this amplification step with nanopore sequencing, we identified >95% annotated L1s from C57BL/6 genomic DNA using only 200 000 sequencing reads. In the process, we discovered 82 unannotated L1 insertions from a single C57BL/6 genome. Most of these unannotated L1s were near repetitive sequence and were not found with short-read TIPseq. We used nanoTIPseq on individual mouse breast cancer cells and were able to identify the annotated and unannotated L1s, as well as new insertions specific to individual cells, providing proof of principle for using nanoTIPseq to interrogate retrotransposition activity at the single-cell level in vivo.
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Affiliation(s)
- Xuanming Zhang
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Ivana Celic
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Hannah Mitchell
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Sam Stuckert
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Lalitha Vedula
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Jeffrey S Han
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
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Saha K, Nielsen GI, Nandani R, Kong L, Ye P, An W. YY1 is a transcriptional activator of mouse LINE-1 Tf subfamily. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.03.573552. [PMID: 38260579 PMCID: PMC10802269 DOI: 10.1101/2024.01.03.573552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Long interspersed element type 1 (LINE-1, L1) is an active autonomous transposable element (TE) in the human genome. The first step of L1 replication is transcription, which is controlled by an internal RNA polymerase II promoter in the 5' untranslated region (UTR) of a full-length L1. It has been shown that transcription factor YY1 binds to a conserved sequence motif at the 5' end of the human L1 5'UTR and dictates where transcription initiates but not the level of transcription. Putative YY1-binding motifs have been predicted in the 5'UTRs of two distinct mouse L1 subfamilies, Tf and Gf. Using site-directed mutagenesis, in vitro binding, and gene knockdown assays, we experimentally tested the role of YY1 in mouse L1 transcription. Our results indicate that Tf, but not Gf subfamily, harbors functional YY1-binding sites in its 5'UTR monomers. In contrast to its role in human L1, YY1 functions as a transcriptional activator for the mouse Tf subfamily. Furthermore, YY1-binding motifs are solely responsible for the synergistic interaction between monomers, consistent with a model wherein distant monomers act as enhancers for mouse L1 transcription. The abundance of YY1-binding sites in Tf elements also raise important implications for gene regulation at the genomic level.
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Affiliation(s)
- Karabi Saha
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
| | - Grace I. Nielsen
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
| | - Raj Nandani
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
| | - Lingqi Kong
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
| | - Ping Ye
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
| | - Wenfeng An
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD 57007, USA
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3
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Wei C, Yan X, Mann JM, Geng R, Xie H, Demireva EY, Sun L, Ding D, Chen C. PNLDC1 catalysis and postnatal germline function are required for piRNA trimming, LINE1 silencing, and spermatogenesis in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.26.573375. [PMID: 38234819 PMCID: PMC10793440 DOI: 10.1101/2023.12.26.573375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
PIWI-interacting RNAs (piRNAs) play critical and conserved roles in transposon silencing and gene regulation in the animal germline. Two distinct piRNA populations are present during mouse spermatogenesis: pre-pachytene piRNAs in fetal/neonatal testes and pachytene piRNAs in adult testes. PNLDC1 is required for both pre-pachytene piRNA and pachytene piRNA 3' end maturation in multiple species. However, whether PNLDC1 is the bona fide piRNA trimmer and the physiological role of 3' trimming of two distinct piRNA populations in spermatogenesis remain unclear. Here, by inactivating Pnldc1 exonuclease activity in vitro and in mice, we reveal that PNLDC1 trimmer activity is required for both pre-pachytene piRNA and pachytene piRNA 3' end trimming and male fertility. Furthermore, conditional inactivation of Pnldc1 in postnatal germ cells causes LINE1 transposon de-repression and spermatogenic arrest in mice. This indicates that pachytene piRNA trimming, but not pre-pachytene piRNA trimming, is essential for mouse germ cell development and transposon silencing. Our findings highlight the potential of inhibiting germline piRNA trimmer activity as a potential means for male contraception.
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Affiliation(s)
- Chao Wei
- Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Xiaoyuan Yan
- Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Jeffrey M. Mann
- Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA
| | - Ruirong Geng
- Shanghai Key Laboratory of Maternal and Fetal Medicine, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Huirong Xie
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, Michigan 48824, USA
| | - Elena Y. Demireva
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, Michigan 48824, USA
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Deqiang Ding
- Shanghai Key Laboratory of Maternal and Fetal Medicine, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Chen Chen
- Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA
- Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan 49503, USA
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Mendez-Dorantes C, Burns KH. LINE-1 retrotransposition and its deregulation in cancers: implications for therapeutic opportunities. Genes Dev 2023; 37:948-967. [PMID: 38092519 PMCID: PMC10760644 DOI: 10.1101/gad.351051.123] [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] [Indexed: 12/28/2023]
Abstract
Long interspersed element 1 (LINE-1) is the only protein-coding transposon that is active in humans. LINE-1 propagates in the genome using RNA intermediates via retrotransposition. This activity has resulted in LINE-1 sequences occupying approximately one-fifth of our genome. Although most copies of LINE-1 are immobile, ∼100 copies are retrotransposition-competent. Retrotransposition is normally limited via epigenetic silencing, DNA repair, and other host defense mechanisms. In contrast, LINE-1 overexpression and retrotransposition are hallmarks of cancers. Here, we review mechanisms of LINE-1 regulation and how LINE-1 may promote genetic heterogeneity in tumors. Finally, we discuss therapeutic strategies to exploit LINE-1 biology in cancers.
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Affiliation(s)
- Carlos Mendez-Dorantes
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA;
- Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, USA
| | - Kathleen H Burns
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA;
- Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, USA
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5
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Zhang X, Celic I, Mitchell H, Stuckert S, Vedula L, Han JS. Comprehensive profiling of L1 retrotransposons in mouse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.13.566638. [PMID: 38014156 PMCID: PMC10680791 DOI: 10.1101/2023.11.13.566638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
L1 elements are retrotransposons currently active in mammals. Although L1s are typically silenced in most normal tissues, elevated L1 expression is associated with a variety of conditions, including cancer, aging, infertility, and neurological disease. These associations have raised interest in the mapping of human endogenous de novo L1 insertions, and a variety of methods have been developed for this purpose. Adapting these methods to mouse genomes would allow us to monitor endogenous in vivo L1 activity in controlled, experimental conditions using mouse disease models. Here we use a modified version of transposon insertion profiling, called nanoTIPseq, to selectively enrich young mouse L1s. By linking this amplification step with nanopore sequencing, we identified >95% annotated L1s from C57BL/6 genomic DNA using only 200,000 sequencing reads. In the process, we discovered 82 unannotated L1 insertions from a single C57BL/6 genome. Most of these unannotated L1s were near repetitive sequence and were not found with short-read TIPseq. We used nanoTIPseq on individual mouse breast cancer cells and were able to identify the annotated and unannotated L1s, as well as new insertions specific to individual cells, providing proof of principle for using nanoTIPseq to interrogate retrotransposition activity at the single cell level in vivo .
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6
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Wei C, Jing J, Yan X, Mann JM, Geng R, Xie H, Demireva EY, Hess RA, Ding D, Chen C. MIWI N-terminal RG motif promotes efficient pachytene piRNA production and spermatogenesis independent of LINE1 transposon silencing. PLoS Genet 2023; 19:e1011031. [PMID: 37956204 PMCID: PMC10681313 DOI: 10.1371/journal.pgen.1011031] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 11/27/2023] [Accepted: 10/24/2023] [Indexed: 11/15/2023] Open
Abstract
PIWI proteins and their associated piRNAs act to silence transposons and promote gametogenesis. Murine PIWI proteins MIWI, MILI, and MIWI2 have multiple arginine and glycine (RG)-rich motifs at their N-terminal domains. Despite being known as docking sites for the TDRD family proteins, the in vivo regulatory roles for these RG motifs in directing PIWI in piRNA biogenesis and spermatogenesis remain elusive. To investigate the functional significance of RG motifs in mammalian PIWI proteins in vivo, we genetically engineered an arginine to lysine (RK) point mutation of a conserved N-terminal RG motif in MIWI in mice. We show that this tiny MIWI RG motif is indispensable for piRNA biogenesis and male fertility. The RK mutation in the RG motif disrupts MIWI-TDRKH interaction and impairs enrichment of MIWI to the intermitochondrial cement (IMC) for efficient piRNA production. Despite significant overall piRNA level reduction, piRNA trimming and maturation are not affected by the RK mutation. Consequently, MiwiRK mutant mice show chromatoid body malformation, spermatogenic arrest, and male sterility. Surprisingly, LINE1 transposons are effectively silenced in MiwiRK mutant mice, indicating a LINE1-independent cause of germ cell arrest distinctive from Miwi knockout mice. These findings reveal a crucial function of the RG motif in directing PIWI proteins to engage in efficient piRNA production critical for germ cell progression and highlight the functional importance of the PIWI N-terminal motifs in regulating male fertility.
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Affiliation(s)
- Chao Wei
- Department of Animal Science, Michigan State University, East Lansing, Michigan, United States of America
| | - Jiongjie Jing
- Shanghai Key Laboratory of Maternal and Fetal Medicine, Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiaoyuan Yan
- Department of Animal Science, Michigan State University, East Lansing, Michigan, United States of America
| | - Jeffrey M. Mann
- Department of Animal Science, Michigan State University, East Lansing, Michigan, United States of America
| | - Ruirong Geng
- Shanghai Key Laboratory of Maternal and Fetal Medicine, Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Huirong Xie
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, Michigan, United States of America
| | - Elena Y. Demireva
- Transgenic and Genome Editing Facility, Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, Michigan, United States of America
| | - Rex A. Hess
- Department of Comparative Biosciences, University of Illinois, Urbana, Illinois, United States of America
| | - Deqiang Ding
- Shanghai Key Laboratory of Maternal and Fetal Medicine, Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Chen Chen
- Department of Animal Science, Michigan State University, East Lansing, Michigan, United States of America
- Reproductive and Developmental Sciences Program, Michigan State University, East Lansing, Michigan, United States of America
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, Michigan, United States of America
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Bona N, Crossan GP. Fanconi anemia DNA crosslink repair factors protect against LINE-1 retrotransposition during mouse development. Nat Struct Mol Biol 2023; 30:1434-1445. [PMID: 37580626 PMCID: PMC10584689 DOI: 10.1038/s41594-023-01067-8] [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: 07/05/2022] [Accepted: 07/13/2023] [Indexed: 08/16/2023]
Abstract
Long interspersed nuclear element 1 (LINE-1) is the only autonomous retrotransposon in humans and new integrations are a major source of genetic variation between individuals. These events can also lead to de novo germline mutations, giving rise to heritable genetic diseases. Recently, a role for DNA repair in regulating these events has been identified. Here we find that Fanconi anemia (FA) DNA crosslink repair factors act in a common pathway to prevent retrotransposition. We purify recombinant SLX4-XPF-ERCC1, the crosslink repair incision complex, and find that it cleaves putative nucleic acid intermediates of retrotransposition. Mice deficient in upstream crosslink repair signaling (FANCA), a downstream component (FANCD2) or the nuclease XPF-ERCC1 show increased LINE-1 retrotransposition in vivo. Organisms limit retrotransposition through transcriptional silencing but this protection is attenuated during early development leaving the zygote vulnerable. We find that during this window of vulnerability, DNA crosslink repair acts as a failsafe to prevent retrotransposition. Together, our results indicate that the FA DNA crosslink repair pathway acts together to protect against mutation by restricting LINE-1 retrotransposition.
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Loubalova Z, Konstantinidou P, Haase AD. Themes and variations on piRNA-guided transposon control. Mob DNA 2023; 14:10. [PMID: 37660099 PMCID: PMC10474768 DOI: 10.1186/s13100-023-00298-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 08/21/2023] [Indexed: 09/04/2023] Open
Abstract
PIWI-interacting RNAs (piRNAs) are responsible for preventing the movement of transposable elements in germ cells and protect the integrity of germline genomes. In this review, we examine the common elements of piRNA-guided silencing as well as the differences observed between species. We have categorized the mechanisms of piRNA biogenesis and function into modules. Individual PIWI proteins combine these modules in various ways to produce unique PIWI-piRNA pathways, which nevertheless possess the ability to perform conserved functions. This modular model incorporates conserved core mechanisms and accommodates variable co-factors. Adaptability is a hallmark of this RNA-based immune system. We believe that considering the differences in germ cell biology and resident transposons in different organisms is essential for placing the variations observed in piRNA biology into context, while still highlighting the conserved themes that underpin this process.
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Affiliation(s)
- Zuzana Loubalova
- National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Parthena Konstantinidou
- National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Astrid D Haase
- National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
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Mauro M, Wei S, Breborowicz A, Li X, Bognanni C, Fuller Z, Philipp T, McDonald T, Lattin MT, Williams Z. Endogenous retrotransposons cause catastrophic deoxyribonucleic acid damage in human trophoblasts. F&S SCIENCE 2023; 4:200-210. [PMID: 37225003 DOI: 10.1016/j.xfss.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To determine the mechanistic role of mobile genetic elements in causing widespread DNA damage in primary human trophoblasts. DESIGN Experimental ex vivo study. SETTING Hospital-affiliated University. PATIENT(S) Trophoblasts from a patient with unexplained recurrent pregnancy loss and patients with spontaneous and elective abortions (n = 10). INTERVENTION(S) Biochemical and genetic analysis and modification of primary human trophoblasts. MAIN OUTCOME MEASURE(S) To phenotype and systematically evaluate the underlying pathogenic mechanism for elevated DNA damage observed in trophoblasts derived from a patient with unexplained recurrent pregnancy loss, transcervical embryoscopy, G-band karyotyping, RNA sequencing, quantitative polymerase chain reaction, immunoblotting, biochemical and siRNA assays, and whole-genome sequencing were performed. RESULT(S) Transcervical embryoscopy revealed a severely dysmorphic embryo that was euploid on G-band karyotyping. RNA sequencing was notable for markedly elevated LINE-1 expression, confirmed with quantitative polymerase chain reaction, and that resulted in elevated expression of LINE-1-encoded proteins, as shown by immunoblotting. Immunofluorescence, biochemical and genetic approaches demonstrated that overexpression of LINE-1 caused reversible widespread genomic damage and apoptosis. CONCLUSION(S) Derepression of LINE-1 elements in early trophoblasts results in reversible but widespread DNA damage.
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Affiliation(s)
- Maurizio Mauro
- Department of Obstetrics and Gynecology, Columbia University Fertility Center, Columbia University Medical Center, New York, New York; Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, New York
| | - Shan Wei
- Department of Obstetrics and Gynecology, Columbia University Fertility Center, Columbia University Medical Center, New York, New York
| | - Andrzej Breborowicz
- Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, New York
| | - Xin Li
- Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, New York
| | - Claudia Bognanni
- The Rockefeller University, Howard Hughes Medical Institute, and Laboratory of RNA Molecular Biology, New York, New York
| | - Zachary Fuller
- Department of Biological Sciences, Columbia University, New York, New York
| | - Thomas Philipp
- Institute of Clinical Gynecology and Obstetrics, Danube Hospital, Vienna, Austria
| | - Torrin McDonald
- Department of Obstetrics and Gynecology, Columbia University Fertility Center, Columbia University Medical Center, New York, New York
| | - Miriam Temmeh Lattin
- Department of Obstetrics and Gynecology, Columbia University Fertility Center, Columbia University Medical Center, New York, New York
| | - Zev Williams
- Department of Obstetrics and Gynecology, Columbia University Fertility Center, Columbia University Medical Center, New York, New York.
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Tan K, Wilkinson MF. Developmental regulators moonlighting as transposons defense factors. Andrology 2023; 11:891-903. [PMID: 36895139 PMCID: PMC11162177 DOI: 10.1111/andr.13427] [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: 01/11/2023] [Revised: 02/17/2023] [Accepted: 03/04/2023] [Indexed: 03/11/2023]
Abstract
BACKGROUND The germline perpetuates genetic information across generations. To maintain the integrity of the germline, transposable elements in the genome must be silenced, as these mobile elements would otherwise engender widespread mutations passed on to subsequent generations. There are several well-established mechanisms that are dedicated to providing defense against transposable elements, including DNA methylation, RNA interference, and the PIWI-interacting RNA pathway. OBJECTIVES Recently, several studies have provided evidence that transposon defense is not only provided by factors dedicated to this purpose but also factors with other roles, including in germline development. Many of these are transcription factors. Our objective is to summarize what is known about these "bi-functional" transcriptional regulators. MATERIALS AND METHODS Literature search. RESULTS AND CONCLUSION We summarize the evidence that six transcriptional regulators-GLIS3, MYBL1, RB1, RHOX10, SETDB1, and ZBTB16-are both developmental regulators and transposable element-defense factors. These factors act at different stages of germ cell development, including in pro-spermatogonia, spermatogonial stem cells, and spermatocytes. Collectively, the data suggest a model in which specific key transcriptional regulators have acquired multiple functions over evolutionary time to influence developmental decisions and safeguard transgenerational genetic information. It remains to be determined whether their developmental roles were primordial and their transposon defense roles were co-opted, or vice versa.
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Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, California, USA
| | - Miles F. Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, California, USA
- Institute of Genomic Medicine, University of California San Diego, La Jolla, California, USA
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11
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Berteli TS, Wang F, Navarro PA, Kohlrausch FB, Keefe DL. A pilot study of LINE-1 copy number and telomere length with aging in human sperm. J Assist Reprod Genet 2023:10.1007/s10815-023-02857-1. [PMID: 37382785 PMCID: PMC10371944 DOI: 10.1007/s10815-023-02857-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/03/2023] [Indexed: 06/30/2023] Open
Abstract
PURPOSE Unlike other cells in the body, in sperm, telomere length (TL) increases with age. TL can regulate nearby genes, and the subtelomeric region is rich in retrotransposons. We hypothesized that age-related telomere lengthening in sperm might suppress Long Interspersed Element 1 (LINE-1/L1), the only competent retrotransposon in humans. METHODS We measured L1 copy number (L1-CN) and sperm telomere length (STL) from young and older men to evaluate the relationship between age, TL and L1-CN. We also evaluated L1-CN and TL in individual sperm to determine whether these variables influence sperm morphology. STL was assayed by Multiplex quantitative polymerase chain reaction method (mmqPCR) and L1-CN by Quantitative polymerase chain reaction (qPCR). RESULTS We found that STL increased, and L1-CN decreased significantly with paternal age. STL in normal single sperm was significantly higher than in abnormal sperm. L1-CN did not differ between normal and abnormal sperm. Furthermore, morphologically normal sperm have longer telomeres than abnormal sperm. CONCLUSIONS Elongation of telomeres in the male germline could repress retrotransposition, which tends to increase with cellular aging. More studies in larger cohorts across a wide age span are needed to confirm our conclusions and explore their biological and clinical significance.
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Affiliation(s)
- Thalita S Berteli
- Department of Obstetrics and Gynecology, Langone Medical Center, New York University, 462, 1st Avenue, New York, NY, 10016, USA.
- Human Reproduction Division, Department of Gynecology and Obstetrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil.
| | - Fang Wang
- Department of Obstetrics and Gynecology, Langone Medical Center, New York University, 462, 1st Avenue, New York, NY, 10016, USA
| | - Paula A Navarro
- Human Reproduction Division, Department of Gynecology and Obstetrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Fabiana B Kohlrausch
- Department of Obstetrics and Gynecology, Langone Medical Center, New York University, 462, 1st Avenue, New York, NY, 10016, USA
- Human Genetics Laboratory, Fluminense Federal University, Niteroi, RJ, Brazil
| | - David L Keefe
- Department of Obstetrics and Gynecology, Langone Medical Center, New York University, 462, 1st Avenue, New York, NY, 10016, USA
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12
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Diaz VD, Hermann BP. Single-Molecule Fluorescence In Situ Hybridization for Spatial Detection of mRNAs in Sections of Mammalian Testes. Methods Mol Biol 2023; 2656:21-35. [PMID: 37249865 DOI: 10.1007/978-1-0716-3139-3_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Single-molecule fluorescence in situ hybridization (smFISH) enables the detection and localization of individual mRNAs in tissue sections with single-molecule resolution while preserving spatial context, and thus, is a useful tool for examining gene expression in biological systems. In particular, the growing reliance on single-cell RNA sequencing (scRNA-seq) to explore cellular heterogeneity has reinvigorated this approach as a validation tool to spatially re-map mRNA expression patterns described in isolated cells to their parent tissue. While use of antibody-based methods, such as indirect immunofluorescence (IIF), remain popular as validation strategies, smFISH often affords superior specificity and maintains congruency with scRNA-seq. Here, we present a detailed protocol that combines multiplexed smFISH using the RNAscope approach with IIF to co-visualize mRNAs and proteins within sections of mouse testes. We provide step-by-step guidelines from testis preparation through visualization that enables mapping of combinations of up to four mRNA/protein targets in frozen sections on the RNAscope platform.
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Affiliation(s)
- Victoria D Diaz
- Department of Neuroscience, Developmental and Regenerative Biology, The University of Texas at San Antonio, San Antonio, TX, USA
| | - Brian P Hermann
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, TX, USA.
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13
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Angileri KM, Bagia NA, Feschotte C. Transposon control as a checkpoint for tissue regeneration. Development 2022; 149:dev191957. [PMID: 36440631 PMCID: PMC10655923 DOI: 10.1242/dev.191957] [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: 03/11/2022] [Accepted: 10/03/2022] [Indexed: 11/29/2022]
Abstract
Tissue regeneration requires precise temporal control of cellular processes such as inflammatory signaling, chromatin remodeling and proliferation. The combination of these processes forms a unique microenvironment permissive to the expression, and potential mobilization of, transposable elements (TEs). Here, we develop the hypothesis that TE activation creates a barrier to tissue repair that must be overcome to achieve successful regeneration. We discuss how uncontrolled TE activity may impede tissue restoration and review mechanisms by which TE activity may be controlled during regeneration. We posit that the diversification and co-evolution of TEs and host control mechanisms may contribute to the wide variation in regenerative competency across tissues and species.
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Affiliation(s)
- Krista M. Angileri
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
| | - Nornubari A. Bagia
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
| | - Cedric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
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14
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Zhang Z, Zhang N, Guo S, Liu Q, Wang S, Zhang A, Yi D, Zhao J, Li Q, Wang J, Zhang Y, Ma L, Ding J, Cen S, Li X. The Zinc-Finger protein ZCCHC3 inhibits LINE-1 retrotransposition. Front Microbiol 2022; 13:891852. [PMID: 36274734 PMCID: PMC9580041 DOI: 10.3389/fmicb.2022.891852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 09/08/2022] [Indexed: 11/13/2022] Open
Abstract
Long-interspersed element 1 (LINE-1) is an autonomous non-LTR retrotransposon. Its replication can cause mutation and rearrangement of host genomic DNA, which may result in serious genetic diseases. Host cells therefore developed defense strategies to restrict LINE-1 mobilization. In this study, we reported that CCHC-type zinc-finger protein ZCCHC3 can repress LINE-1 retrotransposition, and this activity is closely related to its zinc-finger domain. Further studies show that ZCCHC3 can post-transcriptionally diminish the LINE-1 RNA level. The association of ZCCHC3 with both LINE-1 RNA and ORF1 suggests that ZCCHC3 interacts with LINE-1 RNP and consequently causes its RNA degradation. These data demonstrate collectively that ZCCHC3 contributes to the cellular control of LINE-1 replication.
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15
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Yin Y, Liu XZ, Tian Q, Fan YX, Ye Z, Meng TQ, Wei GH, Xiong CL, Li HG, He X, Zhou LQ. Transcriptome and DNA methylome analysis of peripheral blood samples reveals incomplete restoration and transposable element activation after 3-months recovery of COVID-19. Front Cell Dev Biol 2022; 10:1001558. [PMID: 36263014 PMCID: PMC9574079 DOI: 10.3389/fcell.2022.1001558] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 09/15/2022] [Indexed: 01/08/2023] Open
Abstract
Comprehensive analyses showed that SARS-CoV-2 infection caused COVID-19 and induced strong immune responses and sometimes severe illnesses. However, cellular features of recovered patients and long-term health consequences remain largely unexplored. In this study, we collected peripheral blood samples from nine recovered COVID-19 patients (median age of 36 years old) from Hubei province, China, 3 months after discharge as well as 5 age- and gender-matched healthy controls; and carried out RNA-seq and whole-genome bisulfite sequencing to identify hallmarks of recovered COVID-19 patients. Our analyses showed significant changes both in transcript abundance and DNA methylation of genes and transposable elements (TEs) in recovered COVID-19 patients. We identified 425 upregulated genes, 214 downregulated genes, and 18,516 differentially methylated regions (DMRs) in total. Aberrantly expressed genes and DMRs were found to be associated with immune responses and other related biological processes, implicating prolonged overreaction of the immune system in response to SARS-CoV-2 infection. Notably, a significant amount of TEs was aberrantly activated and their activation was positively correlated with COVID-19 severity. Moreover, differentially methylated TEs may regulate adjacent gene expression as regulatory elements. Those identified transcriptomic and epigenomic signatures define and drive the features of recovered COVID-19 patients, helping determine the risks of long COVID-19, and guiding clinical intervention.
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Affiliation(s)
- Ying Yin
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-zhao Liu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Qing Tian
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yi-xian Fan
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Zhen Ye
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tian-qing Meng
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Gong-hong Wei
- MOE Key Laboratory of Metabolism and Molecular Medicine, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University Shanghai Cancer Center, Shanghai Medical College of Fudan University, Shanghai, China
| | - Cheng-liang Xiong
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hong-gang Li
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- *Correspondence: Hong-gang Li, ; Ximiao He, ; Li-quan Zhou,
| | - Ximiao He
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Hong-gang Li, ; Ximiao He, ; Li-quan Zhou,
| | - Li-quan Zhou
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- *Correspondence: Hong-gang Li, ; Ximiao He, ; Li-quan Zhou,
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16
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Son JH, Do H, Han J. Intragenic L1 Insertion: One Possibility of Brain Disorder. Life (Basel) 2022; 12:life12091425. [PMID: 36143463 PMCID: PMC9505610 DOI: 10.3390/life12091425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 08/29/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
Long interspersed nuclear element 1 (LINE1, L1) is a retrotransposon comprising ~17% of the human genome. A subset of L1s maintains the potential to mobilize and alter the genomic landscape, consequently contributing to the change in genome integrity and gene expression. L1 retrotransposition occurs in the human brain regardless of disease status. However, in the brain of patients with various brain diseases, the expression level and copy number of L1 are significantly increased. In this review, we briefly introduce the methodologies applied to measure L1 mobility and identify genomic loci where new insertion of L1 occurs in the brain. Then, we present a list of genes disrupted by L1 transposition in the genome of patients with brain disorders. Finally, we discuss the association between genes disrupted by L1 and relative brain disorders.
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Affiliation(s)
- Ji-Hoon Son
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon 34141, Korea
| | - Hyunsu Do
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon 34141, Korea
| | - Jinju Han
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon 34141, Korea
- BioMedical Research Center, KAIST, Daejeon 34141, Korea
- Correspondence:
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17
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Arora R, Bodak M, Penouty L, Hackman C, Ciaudo C. Sequestration of
LINE
‐1 in cytosolic aggregates by
MOV10
restricts retrotransposition. EMBO Rep 2022; 23:e54458. [PMID: 35856394 PMCID: PMC9442310 DOI: 10.15252/embr.202154458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 06/22/2022] [Accepted: 06/30/2022] [Indexed: 11/09/2022] Open
Affiliation(s)
- Rajika Arora
- Swiss Federal Institute of Technology Zurich IMHS, Chair of RNAi and Genome Integrity Zurich Switzerland
| | - Maxime Bodak
- Swiss Federal Institute of Technology Zurich IMHS, Chair of RNAi and Genome Integrity Zurich Switzerland
| | - Laura Penouty
- Swiss Federal Institute of Technology Zurich IMHS, Chair of RNAi and Genome Integrity Zurich Switzerland
| | - Cindy Hackman
- Swiss Federal Institute of Technology Zurich IMHS, Chair of RNAi and Genome Integrity Zurich Switzerland
| | - Constance Ciaudo
- Swiss Federal Institute of Technology Zurich IMHS, Chair of RNAi and Genome Integrity Zurich Switzerland
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18
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Lee Y, Ha U, Moon S. Ongoing endeavors to detect mobilization of transposable elements. BMB Rep 2022. [PMID: 35725016 PMCID: PMC9340088 DOI: 10.5483/bmbrep.2022.55.7.088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transposable elements (TEs) are DNA sequences capable of mobilization from one location to another in the genome. Since the discovery of ‘Dissociation (Dc) locus’ by Barbara McClintock in maize (1), mounting evidence in the era of genomics indicates that a significant fraction of most eukaryotic genomes is composed of TE sequences, involving in various aspects of biological processes such as development, physiology, diseases and evolution. Although technical advances in genomics have discovered numerous functional impacts of TE across species, our understanding of TEs is still ongoing process due to challenges resulted from complexity and abundance of TEs in the genome. In this mini-review, we briefly summarize biology of TEs and their impacts on the host genome, emphasizing importance of understanding TE landscape in the genome. Then, we introduce recent endeavors especially in vivo retrotransposition assays and long read sequencing technology for identifying de novo insertions/TE polymorphism, which will broaden our knowledge of extraordinary relationship between genomic cohabitants and their host.
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Affiliation(s)
- Yujeong Lee
- Department of Biological Sciences, Kangwon National University, Chuncheon 24341, Korea
| | - Una Ha
- Department of Biological Sciences, Kangwon National University, Chuncheon 24341, Korea
| | - Sungjin Moon
- Department of Biological Sciences, Kangwon National University, Chuncheon 24341, Korea
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19
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Costes V, Chaulot-Talmon A, Sellem E, Perrier JP, Aubert-Frambourg A, Jouneau L, Pontlevoy C, Hozé C, Fritz S, Boussaha M, Le Danvic C, Sanchez MP, Boichard D, Schibler L, Jammes H, Jaffrézic F, Kiefer H. Predicting male fertility from the sperm methylome: application to 120 bulls with hundreds of artificial insemination records. Clin Epigenetics 2022; 14:54. [PMID: 35477426 PMCID: PMC9047354 DOI: 10.1186/s13148-022-01275-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 04/08/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Conflicting results regarding alterations to sperm DNA methylation in cases of spermatogenesis defects, male infertility and poor developmental outcomes have been reported in humans. Bulls used for artificial insemination represent a relevant model in this field, as the broad dissemination of bull semen considerably alleviates confounding factors and enables the precise assessment of male fertility. This study was therefore designed to assess the potential for sperm DNA methylation to predict bull fertility. RESULTS A unique collection of 100 sperm samples was constituted by pooling 2-5 ejaculates per bull from 100 Montbéliarde bulls of comparable ages, assessed as fertile (n = 57) or subfertile (n = 43) based on non-return rates 56 days after insemination. The DNA methylation profiles of these samples were obtained using reduced representation bisulfite sequencing. After excluding putative sequence polymorphisms, 490 fertility-related differentially methylated cytosines (DMCs) were identified, most of which were hypermethylated in subfertile bulls. Interestingly, 46 genes targeted by DMCs are involved in embryonic and fetal development, sperm function and maturation, or have been related to fertility in genome-wide association studies; five of these were further analyzed by pyrosequencing. In order to evaluate the prognostic value of fertility-related DMCs, the sperm samples were split between training (n = 67) and testing (n = 33) sets. Using a Random Forest approach, a predictive model was built from the methylation values obtained on the training set. The predictive accuracy of this model was 72% on the testing set and 72% on individual ejaculates collected from an independent cohort of 20 bulls. CONCLUSION This study, conducted on the largest set of bull sperm samples so far examined in epigenetic analyses, demonstrated that the sperm methylome is a valuable source of male fertility biomarkers. The next challenge is to combine these results with other data on the same sperm samples in order to improve the quality of the model and better understand the interplay between DNA methylation and other molecular features in the regulation of fertility. This research may have potential applications in human medicine, where infertility affects the interaction between a male and a female, thus making it difficult to isolate the male factor.
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Affiliation(s)
- Valentin Costes
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France.,R&D Department, ALLICE, 149 rue de Bercy, 75012, Paris, France.,Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | - Aurélie Chaulot-Talmon
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Eli Sellem
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France.,R&D Department, ALLICE, 149 rue de Bercy, 75012, Paris, France
| | - Jean-Philippe Perrier
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Anne Aubert-Frambourg
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Luc Jouneau
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Charline Pontlevoy
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Chris Hozé
- R&D Department, ALLICE, 149 rue de Bercy, 75012, Paris, France.,Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | - Sébastien Fritz
- R&D Department, ALLICE, 149 rue de Bercy, 75012, Paris, France.,Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | - Mekki Boussaha
- Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | | | - Marie-Pierre Sanchez
- Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | - Didier Boichard
- Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | | | - Hélène Jammes
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France.,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France
| | - Florence Jaffrézic
- Université Paris-Saclay, AgroParisTech, INRAE, GABI, 78350, Jouy-en-Josas, France
| | - Hélène Kiefer
- INRAE, BREED, Université Paris-Saclay, UVSQ, 78350, Jouy-en-Josas, France. .,Ecole Nationale Vétérinaire d'Alfort, BREED, 94700, Maisons-Alfort, France.
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20
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Domazet-Lošo T. mRNA Vaccines: Why Is the Biology of Retroposition Ignored? Genes (Basel) 2022; 13:719. [PMID: 35627104 PMCID: PMC9141755 DOI: 10.3390/genes13050719] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/14/2022] [Accepted: 04/15/2022] [Indexed: 02/07/2023] Open
Abstract
The major advantage of mRNA vaccines over more conventional approaches is their potential for rapid development and large-scale deployment in pandemic situations. In the current COVID-19 crisis, two mRNA COVID-19 vaccines have been conditionally approved and broadly applied, while others are still in clinical trials. However, there is no previous experience with the use of mRNA vaccines on a large scale in the general population. This warrants a careful evaluation of mRNA vaccine safety properties by considering all available knowledge about mRNA molecular biology and evolution. Here, I discuss the pervasive claim that mRNA-based vaccines cannot alter genomes. Surprisingly, this notion is widely stated in the mRNA vaccine literature but never supported by referencing any primary scientific papers that would specifically address this question. This discrepancy becomes even more puzzling if one considers previous work on the molecular and evolutionary aspects of retroposition in murine and human populations that clearly documents the frequent integration of mRNA molecules into genomes, including clinical contexts. By performing basic comparisons, I show that the sequence features of mRNA vaccines meet all known requirements for retroposition using L1 elements-the most abundant autonomously active retrotransposons in the human genome. In fact, many factors associated with mRNA vaccines increase the possibility of their L1-mediated retroposition. I conclude that is unfounded to a priori assume that mRNA-based therapeutics do not impact genomes and that the route to genome integration of vaccine mRNAs via endogenous L1 retroelements is easily conceivable. This implies that we urgently need experimental studies that would rigorously test for the potential retroposition of vaccine mRNAs. At present, the insertional mutagenesis safety of mRNA-based vaccines should be considered unresolved.
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Affiliation(s)
- Tomislav Domazet-Lošo
- Laboratory of Evolutionary Genetics, Division of Molecular Biology, Ruđer Bošković Institute, Bijenička Cesta 54, HR-10000 Zagreb, Croatia;
- School of Medicine, Catholic University of Croatia, Ilica 242, HR-10000 Zagreb, Croatia
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21
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Zhou S, Sakashita A, Yuan S, Namekawa SH. Retrotransposons in the Mammalian Male Germline. Sex Dev 2022:1-19. [PMID: 35231923 DOI: 10.1159/000520683] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 10/25/2021] [Indexed: 11/19/2022] Open
Abstract
Retrotransposons are a subset of DNA sequences that constitute a large part of the mammalian genome. They can translocate autonomously or non-autonomously, potentially jeopardizing the heritable germline genome. Retrotransposons coevolved with the host genome, and the germline is the prominent battlefield between retrotransposons and the host genome to maximize their mutual fitness. Host genomes have developed various mechanisms to suppress and control retrotransposons, including DNA methylation, histone modifications, and Piwi-interacting RNA (piRNA), for their own benefit. Thus, rapidly evolved retrotransposons often acquire positive functions, including gene regulation within the germline, conferring reproductive fitness in a species over the course of evolution. The male germline serves as an ideal model to examine the regulation and evolution of retrotransposons, resulting in genomic co-evolution with the host genome. In this review, we summarize and discuss the regulatory mechanisms of retrotransposons, stage-by-stage, during male germ cell development, with a particular focus on mice as an extensively studied mammalian model, highlighting suppression mechanisms and emerging functions of retrotransposons in the male germline.
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Affiliation(s)
- Shumin Zhou
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Akihiko Sakashita
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
| | - Shuiqiao Yuan
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Shenzhen Huazhong University of Science and Technology Research Institute, Shenzhen, China
| | - Satoshi H Namekawa
- Department of Microbiology and Molecular Genetics, University of California, Davis, California, USA
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22
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Abstract
There are strong incentives for human populations to develop antiviral systems. Similarly, genomes that encode antiviral systems have had strong selective advantages. Protein-guided immune systems, which have been well studied in mammals, are necessary for survival in our virus-laden environments. Small RNA–directed antiviral immune systems suppress invasion of cells by non-self genetic material via complementary base pairing with target sequences. These RNA silencing-dependent systems operate in diverse organisms. In mammals, there is strong evidence that microRNAs (miRNAs) regulate endogenous genes important for antiviral immunity, and emerging evidence that virus-derived nucleic acids can be directly targeted by small interfering RNAs (siRNAs), PIWI-interacting RNAs (piRNAs), and transfer RNAs (tRNAs) for protection in some contexts. In this review, we summarize current knowledge of the antiviral functions of each of these small RNA types and consider their conceptual and mechanistic overlap with innate and adaptive protein-guided immunity, including mammalian antiviral cytokines, as well as the prokaryotic RNA-guided immune system, CRISPR. In light of recent successes in delivery of RNA for antiviral purposes, most notably for vaccination, we discuss the potential for development of small noncoding RNA–directed antiviral therapeutics and prophylactics. Viruses are all around us and are likely inside some of the reader’s cells at this moment. Organisms are accommodated to this reality and encode various immune systems to limit virus replication. In mammals, the best studied immune systems are directed by proteins that specifically recognize viruses. These include diverse antibodies and T cell receptors, which recognize viral proteins, and pattern recognition receptors, some of which can recognize viral nucleic acids. In other organisms, including bacteria, immune systems directed by small RNAs are also well known; spacer-derived guide RNAs in CRISPR/Cas immune systems are one prominent example. The small RNAs directing these systems derive their specificity via complementary base pairing with their targets, which include both host and viral nucleic acids. Rather than having “traded in” these systems for more advanced protein-directed systems, increasing evidence supports the perspective that small RNA–directed immune systems remain active in mammalian antiviral immunity in some contexts. Here, we review what is known so far about the emerging roles of mammalian siRNAs, miRNAs, piRNAs, and tRNAs in directing immunity to viruses.
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Affiliation(s)
- Tomoko Takahashi
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, Saitama, Japan
- * E-mail: (TT); (NFP)
| | - Steven M. Heaton
- Genome Immunobiology RIKEN Hakubi Research Team, Cluster for Pioneering Research, RIKEN, Yokohama, Japan
- Center for Integrative Medical Sciences, RIKEN, Yokohama, Japan
| | - Nicholas F. Parrish
- Genome Immunobiology RIKEN Hakubi Research Team, Cluster for Pioneering Research, RIKEN, Yokohama, Japan
- Center for Integrative Medical Sciences, RIKEN, Yokohama, Japan
- * E-mail: (TT); (NFP)
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23
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Programmed DNA elimination: silencing genes and repetitive sequences in somatic cells. Biochem Soc Trans 2021; 49:1891-1903. [PMID: 34665225 DOI: 10.1042/bst20190951] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/25/2021] [Accepted: 09/28/2021] [Indexed: 12/30/2022]
Abstract
In a multicellular organism, the genomes of all cells are in general the same. Programmed DNA elimination is a notable exception to this genome constancy rule. DNA elimination removes genes and repetitive elements in the germline genome to form a reduced somatic genome in various organisms. The process of DNA elimination within an organism is highly accurate and reproducible; it typically occurs during early embryogenesis, coincident with germline-soma differentiation. DNA elimination provides a mechanism to silence selected genes and repeats in somatic cells. Recent studies in nematodes suggest that DNA elimination removes all chromosome ends, resolves sex chromosome fusions, and may also promote the birth of novel genes. Programmed DNA elimination processes are diverse among species, suggesting DNA elimination likely has evolved multiple times in different taxa. The growing list of organisms that undergo DNA elimination indicates that DNA elimination may be more widespread than previously appreciated. These various organisms will serve as complementary and comparative models to study the function, mechanism, and evolution of programmed DNA elimination in metazoans.
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24
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Transposable Element Dynamics and Regulation during Zygotic Genome Activation in Mammalian Embryos and Embryonic Stem Cell Model Systems. Stem Cells Int 2021; 2021:1624669. [PMID: 34691189 PMCID: PMC8536462 DOI: 10.1155/2021/1624669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/31/2021] [Accepted: 09/08/2021] [Indexed: 12/25/2022] Open
Abstract
Transposable elements (TEs) are mobile genetic sequences capable of duplicating and reintegrating at new regions within the genome. A growing body of evidence has demonstrated that these elements play important roles in host genome evolution, despite being traditionally viewed as parasitic elements. To prevent ectopic activation of TE transposition and transcription, they are epigenetically silenced in most somatic tissues. Intriguingly, a specific class of TEs-retrotransposons-is transiently expressed at discrete phases during mammalian development and has been linked to the establishment of totipotency during zygotic genome activation (ZGA). While mechanisms controlling TE regulation in somatic tissues have been extensively studied, the significance underlying the unique transcriptional reactivation of retrotransposons during ZGA is only beginning to be uncovered. In this review, we summarize the expression dynamics of key retrotransposons during ZGA, focusing on findings from in vivo totipotent embryos and in vitro totipotent-like embryonic stem cells (ESCs). We then dissect the functions of retrotransposons and discuss how their transcriptional activities are finetuned during early stages of mammalian development.
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25
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Newkirk SJ, An W. UHRF1: a jack of all trades, and a master epigenetic regulator during spermatogenesis. Biol Reprod 2021; 102:1147-1152. [PMID: 32101289 DOI: 10.1093/biolre/ioaa026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 02/26/2020] [Indexed: 01/03/2023] Open
Affiliation(s)
- Simon J Newkirk
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, USA
| | - Wenfeng An
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, USA
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26
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Ramakrishna NB, Miska EA. Who watches the watchmen? RNAi pathway-derived ribosomal small RNAs burgeon in absence of piRNAs. Dev Cell 2021; 56:2269-2270. [PMID: 34428395 DOI: 10.1016/j.devcel.2021.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Instead of causing immediate sterility, loss of the C. elegans PIWI protein PRG-1 leads to accumulated infertility after tens of generations. In this issue of Developmental Cell, Wahba et al. show that this correlates with aberrant RNA interference pathway-dependent feed forward amplification of ribosomal siRNAs-the proposed accumulative sterility factor.
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Affiliation(s)
- Navin B Ramakrishna
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, UK; Department of Genetics, University of Cambridge, Downing Street, Cambridge, UK
| | - Eric A Miska
- Wellcome/CRUK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, UK; Department of Genetics, University of Cambridge, Downing Street, Cambridge, UK; Wellcome Sanger Institute, Wellcome Trust Genome Campus, Cambridge, UK.
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27
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Abstract
Transposable elements (TEs) are mobile sequences that engender widespread mutations and thus are a major hazard that must be silenced. The most abundant active class of TEs in mammalian genomes is long interspersed element class 1 (LINE1). Here, we report that LINE1 transposition is suppressed in the male germline by transcription factors encoded by a rapidly evolving X-linked homeobox gene cluster. LINE1 transposition is repressed by many members of this RHOX transcription factor family, including those with different patterns of expression during spermatogenesis. One family member-RHOX10-suppresses LINE1 transposition during fetal development in vivo when the germline would otherwise be susceptible to LINE1 activation because of epigenetic reprogramming. We provide evidence that RHOX10 suppresses LINE transposition by inducing Piwil2, which encodes a key component in the Piwi-interacting RNA pathway that protects against TEs. The ability of RHOX transcription factors to suppress LINE1 is conserved in humans but is lost in RHOXF2 mutants from several infertile human patients, raising the possibility that loss of RHOXF2 causes human infertility by allowing uncontrolled LINE1 expression in the germline. Together, our results support a model in which the Rhox gene cluster is in an evolutionary arms race with TEs, resulting in expansion of the Rhox gene cluster to suppress TEs in different biological contexts.
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28
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Bergero R, Ellis P, Haerty W, Larcombe L, Macaulay I, Mehta T, Mogensen M, Murray D, Nash W, Neale MJ, O'Connor R, Ottolini C, Peel N, Ramsey L, Skinner B, Suh A, Summers M, Sun Y, Tidy A, Rahbari R, Rathje C, Immler S. Meiosis and beyond - understanding the mechanistic and evolutionary processes shaping the germline genome. Biol Rev Camb Philos Soc 2021; 96:822-841. [PMID: 33615674 PMCID: PMC8246768 DOI: 10.1111/brv.12680] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/15/2020] [Accepted: 12/15/2020] [Indexed: 12/11/2022]
Abstract
The separation of germ cell populations from the soma is part of the evolutionary transition to multicellularity. Only genetic information present in the germ cells will be inherited by future generations, and any molecular processes affecting the germline genome are therefore likely to be passed on. Despite its prevalence across taxonomic kingdoms, we are only starting to understand details of the underlying micro-evolutionary processes occurring at the germline genome level. These include segregation, recombination, mutation and selection and can occur at any stage during germline differentiation and mitotic germline proliferation to meiosis and post-meiotic gamete maturation. Selection acting on germ cells at any stage from the diploid germ cell to the haploid gametes may cause significant deviations from Mendelian inheritance and may be more widespread than previously assumed. The mechanisms that affect and potentially alter the genomic sequence and allele frequencies in the germline are pivotal to our understanding of heritability. With the rise of new sequencing technologies, we are now able to address some of these unanswered questions. In this review, we comment on the most recent developments in this field and identify current gaps in our knowledge.
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Affiliation(s)
- Roberta Bergero
- Institute of Evolutionary BiologyUniversity of EdinburghEdinburghEH9 3JTU.K.
| | - Peter Ellis
- School of BiosciencesUniversity of KentCanterburyCT2 7NJU.K.
| | | | - Lee Larcombe
- Applied Exomics LtdStevenage Bioscience CatalystStevenageSG1 2FXU.K.
| | - Iain Macaulay
- Earlham InstituteNorwich Research ParkNorwichNR4 7UZU.K.
| | - Tarang Mehta
- Earlham InstituteNorwich Research ParkNorwichNR4 7UZU.K.
| | - Mette Mogensen
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichNR4 7TJU.K.
| | - David Murray
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichNR4 7TJU.K.
| | - Will Nash
- Earlham InstituteNorwich Research ParkNorwichNR4 7UZU.K.
| | - Matthew J. Neale
- Genome Damage and Stability Centre, School of Life SciencesUniversity of SussexBrightonBN1 9RHU.K.
| | | | | | - Ned Peel
- Earlham InstituteNorwich Research ParkNorwichNR4 7UZU.K.
| | - Luke Ramsey
- The James Hutton InstituteInvergowrieDundeeDD2 5DAU.K.
| | - Ben Skinner
- School of Life SciencesUniversity of EssexColchesterCO4 3SQU.K.
| | - Alexander Suh
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichNR4 7TJU.K.
- Department of Organismal BiologyUppsala UniversityNorbyvägen 18DUppsala752 36Sweden
| | - Michael Summers
- School of BiosciencesUniversity of KentCanterburyCT2 7NJU.K.
- The Bridge Centre1 St Thomas Street, London BridgeLondonSE1 9RYU.K.
| | - Yu Sun
- Norwich Medical SchoolUniversity of East AngliaNorwich Research Park, Colney LnNorwichNR4 7UGU.K.
| | - Alison Tidy
- School of BiosciencesUniversity of Nottingham, Plant Science, Sutton Bonington CampusSutton BoningtonLE12 5RDU.K.
| | | | - Claudia Rathje
- School of BiosciencesUniversity of KentCanterburyCT2 7NJU.K.
| | - Simone Immler
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichNR4 7TJU.K.
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29
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Kong L, Wu Y, Hu W, Liu L, Xue Y, Liang G. Mechanisms underlying reproductive toxicity induced by nickel nanoparticles identified by comprehensive gene expression analysis in GC-1 spg cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 275:116556. [PMID: 33588191 DOI: 10.1016/j.envpol.2021.116556] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/04/2021] [Accepted: 01/17/2021] [Indexed: 06/12/2023]
Abstract
The public around the world is increasingly concerned about male reproductive health. The impact of nickel nanoparticles (Ni NPs) on male reproductive toxicity including sperm production, motility and fertilizing capacity has been confirmed by our previous researches. In the current study of Ni NPs-inducing toxicity, the expression profiles of piRNAs and their predicted target genes associated with male infertility, were obtained. The results showed that piR-mmu-32362259 was the highest differential expression multiples in both the testis tissues of male mice and GC-1 cells similarly. Notably, piR-mmu-32362259 target gene was significantly enriched in the PI3K-AKT signaling pathway. All these results suggest that piR-mmu-32362259 may affect the occurrence and development of injury in the mouse spermatogenesis process by regulating the PI3K-AKT signaling pathway. In order to verify the result, piR-mmu-32362259 low-expression lentivirus was used to transfect GC-1 cells to establish a stable transfected cell model. The effects of piR-mmu-32362259 on the viability, cycle and apoptosis as well as related protein expression levels of GC-1 cells induced by Ni NPs were detected using CCK8, flow cytometry and western blot assay, respectively. The results showed that low expression of piR-mmu-32362259 could not only alleviate the decrease of GC-1 cell viability, affect the cell cycle and reduce the apoptosis rate, but also significantly affect the expression levels of key proteins and their downstream molecules of PI3K/AKT/mTOR signaling pathway. Collectively, our current results provide a theoretical basis for further exploring the molecular regulatory mechanism of male reproductive toxicity induced by Ni NPs.
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Affiliation(s)
- Lu Kong
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
| | - Yongya Wu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
| | - Wangcheng Hu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
| | - Lin Liu
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
| | - Yuying Xue
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
| | - Geyu Liang
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, 210009, PR China.
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30
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Yin Y, Liu XZ, He X, Zhou LQ. Exogenous Coronavirus Interacts With Endogenous Retrotransposon in Human Cells. Front Cell Infect Microbiol 2021; 11:609160. [PMID: 33732659 PMCID: PMC7959850 DOI: 10.3389/fcimb.2021.609160] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/18/2021] [Indexed: 01/08/2023] Open
Abstract
There is an increased global outbreak of diseases caused by coronaviruses affecting respiratory tracts of birds and mammals. Recent dangerous coronaviruses are MERS-CoV, SARS-CoV, and SARS-CoV-2, causing respiratory illness and even failure of several organs. However, profound impact of coronavirus on host cells remains elusive. In this study, we analyzed transcriptome of MERS-CoV, SARS-CoV, and SARS-CoV-2 infected human lung-derived cells, and observed that infection of these coronaviruses all induced increase of retrotransposon expression with upregulation of TET genes. Upregulation of retrotransposon was also observed in SARS-CoV-2 infected human intestinal organoids. Retrotransposon upregulation may lead to increased genome instability and enhanced expression of genes with readthrough from retrotransposons. Therefore, people with higher basal level of retrotransposon such as cancer patients and aged people may have increased risk of symptomatic infection. Additionally, we show evidence supporting long-term epigenetic inheritance of retrotransposon upregulation. We also observed chimeric transcripts of retrotransposon and SARS-CoV-2 RNA for potential human genome invasion of viral fragments, with the front and the rear part of SARS-CoV-2 genome being easier to form chimeric RNA. Thus, we suggest that primers and probes for nucleic acid detection should be designed in the middle of virus genome to identify live virus with higher probability. In summary, we propose our hypothesis that coronavirus invades human cells and interacts with retrotransposon, eliciting more severe symptoms in patients with underlying diseases. In the treatment of patients with coronavirus infection, it may be necessary to pay more attention to the potential harm contributed by retrotransposon dysregulation.
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Affiliation(s)
- Ying Yin
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-zhao Liu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Ximiao He
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Center for Genomics and Proteomics Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Huazhong University of Science and Technology, Wuhan, China
| | - Li-quan Zhou
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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31
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HRV16 Infection Induces Changes in the Expression of Multiple piRNAs. Virol Sin 2021; 36:736-745. [PMID: 33616891 DOI: 10.1007/s12250-021-00344-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 10/30/2020] [Indexed: 10/22/2022] Open
Abstract
Human rhinovirus (HRV) is one of the most important cold-causing pathogens in humans. Piwi-interacting RNAs (piRNAs) are a recently discovered class of small non-coding RNAs whose best-understood function is to repress mobile element (ME) activity in animal germline. However, the profile of human/host piRNA during HRV infection is largely unknown. Here we performed high-throughput sequencing of piRNAs from H1-HeLa cells infected with HRV16 at 12 h, 24 h, and 36 h. The results showed that 22,151,664, 24,362,486 and 22,726,546 piRNAs displayed differential expression after HRV16 infection for three time points. A significant differential expression of 21 piRNAs was found in all time points and further verified by RT-qPCR, including 7 known piRNAs and 14 newly found piRNAs. In addition, piRNA prediction was performed on Piano using the SVM algorithm and transposon information. It found that novel_pir78110, novel_pir78107, novel_pir78097, novel_pir78094 and novel_pir76584 are associated with the DNA/hobo of Drosophila, Ac of maize and Tam3 of snapdragon (hAT)-Charlie transposon. The novel_pir97924, novel_pir105705 and novel_pir105700 recognize long interspersed nuclear elements 1 (LINE-1). The novel_pir33182 and novel_pir46604 are related to the long terminal repeat (LTR)/(Endogenous Retrovirus1) ERV1 repetitive element. The novel_pir73855 is related to the LTR/ERVK repetitive element. Both novel_pir70108 and novel_pir70106 are associated with the LTR/ERVL-MaLR repetitive element. The novel_pir15900 is associated with the DNA/hAT-Tip100 repetitive element. Overall, our results indicated that rhinovirus infection could reduce the expression of some piRNAs to facilitate upregulation of LINE-1 transcription or retrotransposons' expression, which is helpful to further explore the mechanism of rhinovirus infection.
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32
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Rusetska N, Kober P, Król SK, Boresowicz J, Maksymowicz M, Kunicki J, Bonicki W, Bujko M. Invasive and Noninvasive Nonfunctioning Gonadotroph Pituitary Tumors Differ in DNA Methylation Level of LINE-1 Repetitive Elements. J Clin Med 2021; 10:560. [PMID: 33546126 PMCID: PMC7913198 DOI: 10.3390/jcm10040560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Epigenetic dysregulation plays a role in pituitary tumor pathogenesis. Some differences in DNA methylation were observed between invasive and noninvasive nonfunctioning gonadotroph tumors. This study sought to determine the role of DNA methylation changes in repetitive LINE-1 elements in nonfunctioning gonadotroph pituitary tumors. METHODS We investigated LINE-1 methylation levels in 80 tumors and normal pituitary glands with bisulfite-pyrosequencing. Expression of two LINE-1 open reading frames (L1-ORF1 and L1-ORF2) was analyzed with qRT-PCR in tumor samples and mouse gonadotroph pituitary cells treated with DNA methyltransferase inhibitor. Immunohistochemical staining against L1-ORF1p was also performed in normal pituitary glands and tumors. RESULTS Hypomethylation of LINE-1 was observed in pituitary tumors. Tumors characterized by invasive growth revealed lower LINE-1 methylation level than noninvasive ones. LINE-1 methylation correlated with overall DNA methylation assessed with HM450K arrays and negatively correlated with L1-ORF1 and L1-ORF2 expression. Treatment of αT3-1 gonadotroph cells with 5-Azacytidine clearly increased the level of L1-ORF1 and L1-ORF2 mRNA; however, its effect on LβT2 cells was less pronounced. Immunoreactivity against L1-ORF1p was higher in tumors than normal tissue. No difference in L1-ORF1p expression was observed in invasive and noninvasive tumors. CONCLUSION Hypomethylation of LINE-1 is related to invasive growth and influences transcriptional activity of transposable elements.
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Affiliation(s)
- Natalia Rusetska
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (N.R.); (P.K.); (S.K.K.); (J.B.)
| | - Paulina Kober
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (N.R.); (P.K.); (S.K.K.); (J.B.)
| | - Sylwia Katarzyna Król
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (N.R.); (P.K.); (S.K.K.); (J.B.)
| | - Joanna Boresowicz
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (N.R.); (P.K.); (S.K.K.); (J.B.)
| | - Maria Maksymowicz
- Department of Pathology and Laboratory Diagnostics, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland;
| | - Jacek Kunicki
- Department of Neurosurgery, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (J.K.); (W.B.)
| | - Wiesław Bonicki
- Department of Neurosurgery, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (J.K.); (W.B.)
| | - Mateusz Bujko
- Department of Molecular and Translational Oncology, Maria Sklodowska-Curie National Research Institute of Oncology, 02-781 Warsaw, Poland; (N.R.); (P.K.); (S.K.K.); (J.B.)
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33
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Kohlrausch FB, Berteli TS, Wang F, Navarro PA, Keefe DL. Control of LINE-1 Expression Maintains Genome Integrity in Germline and Early Embryo Development. Reprod Sci 2021; 29:328-340. [PMID: 33481218 DOI: 10.1007/s43032-021-00461-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/06/2021] [Indexed: 11/28/2022]
Abstract
Maintenance of genome integrity in the germline and in preimplantation embryos is crucial for mammalian development. Epigenetic remodeling during primordial germ cell (PGC) and preimplantation embryo development may contribute to genomic instability in these cells, since DNA methylation is an important mechanism to silence retrotransposons. Long interspersed elements 1 (LINE-1 or L1) are the most common autonomous retrotransposons in mammals, corresponding to approximately 17% of the human genome. Retrotransposition events are more frequent in germ cells and in early stages of embryo development compared with somatic cells. It has been shown that L1 activation and expression occurs in germline and is essential for preimplantation development. In this review, we focus on the role of L1 retrotransposon in mouse and human germline and early embryo development and discuss the possible relationship between L1 expression and genomic instability during these stages. Although several studies have addressed L1 expression at different stages of development, the developmental consequences of this expression remain poorly understood. Future research is still needed to highlight the relationship between L1 retrotransposition events and genomic instability during germline and early embryo development.
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Affiliation(s)
- Fabiana B Kohlrausch
- Department of Obstetrics and Gynecology, New York University Langone Medical Center, 462 1st Avenue, New York, NY, 10016, USA.,Departamento de Biologia Geral, Instituto de Biologia, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Thalita S Berteli
- Department of Obstetrics and Gynecology, New York University Langone Medical Center, 462 1st Avenue, New York, NY, 10016, USA.,Departamento de Ginecologia e Obstetrícia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Fang Wang
- Department of Obstetrics and Gynecology, New York University Langone Medical Center, 462 1st Avenue, New York, NY, 10016, USA
| | - Paula A Navarro
- Departamento de Ginecologia e Obstetrícia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - David L Keefe
- Department of Obstetrics and Gynecology, New York University Langone Medical Center, 462 1st Avenue, New York, NY, 10016, USA.
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34
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Grundy EE, Diab N, Chiappinelli KB. Transposable element regulation and expression in cancer. FEBS J 2021; 289:1160-1179. [PMID: 33471418 DOI: 10.1111/febs.15722] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/08/2021] [Accepted: 01/14/2021] [Indexed: 12/11/2022]
Abstract
Approximately 45% of the human genome is composed of transposable elements (TEs). Expression of these elements is tightly regulated during normal development. TEs may be expressed at high levels in embryonic stem cells but are epigenetically silenced in terminally differentiated cells. As part of the global 'epigenetic dysregulation' that cells undergo during transformation from normal to cancer, TEs can lose epigenetic silencing and become transcribed, and, in some cases, active. Here, we summarize recent advances detailing the consequences of TE activation in cancer and describe how these understudied residents of our genome can both aid tumorigenesis and potentially be harnessed for anticancer therapies.
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Affiliation(s)
- Erin E Grundy
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA.,The GW Cancer Center, The George Washington University, Washington, DC, USA.,The Institute for Biomedical Sciences at The George Washington University, Washington, DC, USA
| | - Noor Diab
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA.,The GW Cancer Center, The George Washington University, Washington, DC, USA
| | - Katherine B Chiappinelli
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA.,The GW Cancer Center, The George Washington University, Washington, DC, USA
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35
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Burns KH. Our Conflict with Transposable Elements and Its Implications for Human Disease. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2020; 15:51-70. [PMID: 31977294 DOI: 10.1146/annurev-pathmechdis-012419-032633] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Our genome is a historic record of successive invasions of mobile genetic elements. Like other eukaryotes, we have evolved mechanisms to limit their propagation and minimize the functional impact of new insertions. Although these mechanisms are vitally important, they are imperfect, and a handful of retroelement families remain active in modern humans. This review introduces the intrinsic functions of transposons, the tactics employed in their restraint, and the relevance of this conflict to human pathology. The most straightforward examples of disease-causing transposable elements are germline insertions that disrupt a gene and result in a monogenic disease allele. More enigmatic are the abnormal patterns of transposable element expression in disease states. Changes in transposon regulation and cellular responses to their expression have implicated these sequences in diseases as diverse as cancer, autoimmunity, and neurodegeneration. Distinguishing their epiphenomenal from their pathogenic effects may provide wholly new perspectives on our understanding of disease.
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Affiliation(s)
- Kathleen H Burns
- Department of Pathology, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA;
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36
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Tan M, van Tol HT, Rosenkranz D, Roovers EF, Damen MJ, Stout TA, Wu W, Roelen BA. PIWIL3 Forms a Complex with TDRKH in Mammalian Oocytes. Cells 2020; 9:cells9061356. [PMID: 32486081 PMCID: PMC7349845 DOI: 10.3390/cells9061356] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/15/2020] [Accepted: 05/27/2020] [Indexed: 01/09/2023] Open
Abstract
P-element induced wimpy testis (PIWIs) are crucial guardians of genome integrity, particularly in germ cells. While mammalian PIWIs have been primarily studied in mouse and rat, a homologue for the human PIWIL3 gene is absent in the Muridae family, and hence the unique function of PIWIL3 in germ cells cannot be effectively modeled by mouse knockouts. Herein, we investigated the expression, distribution, and interaction of PIWIL3 in bovine oocytes. We localized PIWIL3 to mitochondria, and demonstrated that PIWIL3 expression is stringently controlled both spatially and temporally before and after fertilization. Moreover, we identified PIWIL3 in a mitochondrial-recruited three-membered complex with Tudor and KH domain-containing protein (TDRKH) and poly(A)-specific ribonuclease-like domain containing 1 (PNLDC1), and demonstrated by mutagenesis that PIWIL3 N-terminal arginines are required for complex assembly. Finally, we sequenced the piRNAs bound to PIWIL3-TDRKH-PNLDC1 and report here that about 50% of these piRNAs map to transposable elements, recapitulating the important role of PIWIL3 in maintaining genome integrity in mammalian oocytes.
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Affiliation(s)
- Minjie Tan
- Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands; (M.T.); (H.T.A.v.T.)
| | - Helena T.A. van Tol
- Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands; (M.T.); (H.T.A.v.T.)
| | - David Rosenkranz
- Johannes Gutenberg-University Mainz, Institute of Organismic and Molecular Evolution, Anselm-Franz-von-Bentzel-Weg 7, 55128 Mainz, Germany;
| | - Elke F. Roovers
- Biology of Non-coding RNA Group, Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz, Germany;
| | - Mirjam J. Damen
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands;
- Netherlands Proteomics Centre, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Tom A.E. Stout
- Equine Sciences, Department Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands;
| | - Wei Wu
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands;
- Netherlands Proteomics Centre, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Correspondence: (W.W.); (B.A.J.R.)
| | - Bernard A.J. Roelen
- Embryology, Anatomy and Physiology, Department Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
- Correspondence: (W.W.); (B.A.J.R.)
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37
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Newkirk SJ, Kong L, Jones MM, Habben CE, Dilts VL, Ye P, An W. Subfamily-specific quantification of endogenous mouse L1 retrotransposons by droplet digital PCR. Anal Biochem 2020; 601:113779. [PMID: 32442414 DOI: 10.1016/j.ab.2020.113779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/06/2020] [Accepted: 05/14/2020] [Indexed: 11/18/2022]
Abstract
Long interspersed element type 1 (LINE-1; L1) mobilizes during early embryogenesis, neurogenesis, and germ cell development, accounting for 25% of disease-causing heritable insertions and 98% of somatic insertions in cancer. To better understand the regulation and impact of L1 mobilization in the genome, reliable methods for measuring L1 copy number variation (CNV) are needed. Here we present a comprehensive analysis of a droplet digital PCR (ddPCR) based method for quantifying endogenous mouse L1. We provide experimental evidence that ddPCR assays can be designed to target specific L1 subfamilies using diagnostic single nucleotide polymorphisms (SNPs). The target and off-target L1 subfamilies form distinct droplet clusters, which were experimentally verified using both synthetic gene fragments and endogenous L1 derived plasmid clones. We further provide a roadmap for in silico assay design and evaluation of target specificity, ddPCR testing, and optimization for L1 CNV quantification. The assay can achieve a sensitivity of 5% CNV with 8 technical replicates. With 24 technical replicates, it can detect 2% CNV because of the increased precision. The same approach will serve as a guide for the development of ddPCR based assays for quantifying human L1 copy number and any other high copy genomic target sequences.
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Affiliation(s)
- Simon J Newkirk
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
| | - Lingqi Kong
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
| | - Mason M Jones
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
| | - Chase E Habben
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
| | - Victoria L Dilts
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
| | - Ping Ye
- Department of Pharmacy Practice, South Dakota State University, Brookings, SD, 57007, United States; Avera Research Institute, Sioux Falls, SD, 57108, United States.
| | - Wenfeng An
- Department of Pharmaceutical Sciences, South Dakota State University, Brookings, SD, 57007, United States.
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38
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Stermer AR, Reyes G, Hall SJ, Boekelheide K. Small RNAs in Rat Sperm Are a Predictive and Sensitive Biomarker of Exposure to the Testicular Toxicant Ethylene Glycol Monomethyl Ether. Toxicol Sci 2020; 169:399-408. [PMID: 30768127 DOI: 10.1093/toxsci/kfz041] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Testicular histology and semen parameters are considered the gold standards when determining male reproductive toxicity. Ethylene glycol monomethyl ether (EGME) is a testicular toxicant with well-described effects on histopathology and sperm parameters. To compare the predictivity and sensitivity of molecular biomarkers of testicular toxicity to the traditional endpoints, small RNAs in the sperm were analyzed by next generation RNA-sequencing (RNA-seq). Adult rats were exposed to 0, 50, 60, or 75 mg/kg EGME by oral gavage for 5 consecutive days. Testis histology, epididymal sperm motility, and sperm small RNAs, including microRNAs (miRNAs), mRNA fragments, piwi-interacting RNAs (piRNAs), and tRNA fragments (tRFs), were analyzed 5 weeks after cessation of exposure. Testicular histology showed a significant dose-dependent increase in retained spermatid heads (RSH), while sperm motility declined with increasing dose. RNA-sequencing of sperm small RNAs was used to identify significant dose-dependent changes in percent mRNA fragments (of total reads), percent miRNAs (of total reads), average tRF length, average piRNA length, and piRNA and tRF length-distributions. Discriminant analysis showed relatively low predictivity of exposure based on RSH or motility compared to the average read length of all assigned RNAs. Benchmark dose (BMD) modeling resulted in a BMD of 62 mg/kg using RSH, whereas average read length of all assigned RNAs resulted in a BMD of 47 mg/kg. These results showed that sperm small RNAs are sensitive and predictive biomarkers of EGME-induced male reproductive toxicity.
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Affiliation(s)
- Angela R Stermer
- Department of pathology and laboratory medicine, Brown University, Providence, Rhode Island 02912
| | - Gerardo Reyes
- Department of pathology and laboratory medicine, Brown University, Providence, Rhode Island 02912
| | - Susan J Hall
- Department of pathology and laboratory medicine, Brown University, Providence, Rhode Island 02912
| | - Kim Boekelheide
- Department of pathology and laboratory medicine, Brown University, Providence, Rhode Island 02912
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39
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Del Re B, Giorgi G. Long INterspersed element-1 mobility as a sensor of environmental stresses. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:465-493. [PMID: 32144842 DOI: 10.1002/em.22366] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Long INterspersed element (LINE-1, L1) retrotransposons are the most abundant transposable elements in the human genome, constituting approximately 17%. They move by a "copy-paste" mechanism, involving reverse transcription of an RNA intermediate and insertion of its cDNA copy at a new site in the genome. L1 retrotransposition (L1-RTP) can cause insertional mutations, alter gene expression, transduce exons, and induce epigenetic dysregulation. L1-RTP is generally repressed; however, a number of observations collected over about 15 years revealed that it can occur in response to environmental stresses. Moreover, emerging evidence indicates that L1-RTP can play a role in the onset of several neurological and oncological diseases in humans. In recent years, great attention has been paid to the exposome paradigm, which proposes that health effects of an environmental factor should be evaluated considering both cumulative environmental exposures and the endogenous processes resulting from the biological response. L1-RTP could be an endogenous process considered for this application. Here, we summarize the current understanding of environmental factors that can affect the retrotransposition of human L1 elements. Evidence indicates that L1-RTP alteration is triggered by numerous and various environmental stressors, such as chemical agents (heavy metals, carcinogens, oxidants, and drugs), physical agents (ionizing and non-ionizing radiations), and experiential factors (voluntary exercise, social isolation, maternal care, and environmental light/dark cycles). These data come from in vitro studies on cell lines and in vivo studies on transgenic animals: future investigations should be focused on physiologically relevant models to gain a better understanding of this topic.
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Affiliation(s)
- Brunella Del Re
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Gianfranco Giorgi
- Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum University of Bologna, Bologna, Italy
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40
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Ryan CP, Kuzawa CW. Germline epigenetic inheritance: Challenges and opportunities for linking human paternal experience with offspring biology and health. Evol Anthropol 2020; 29:180-200. [DOI: 10.1002/evan.21828] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 09/30/2019] [Accepted: 02/21/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Calen P. Ryan
- Department of AnthropologyNorthwestern University Evanston Illinois USA
| | - Christopher W. Kuzawa
- Department of AnthropologyNorthwestern University Evanston Illinois USA
- Institute for Policy Research Northwestern University Evanston Illinois USA
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41
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Percharde M, Sultana T, Ramalho-Santos M. What Doesn't Kill You Makes You Stronger: Transposons as Dual Players in Chromatin Regulation and Genomic Variation. Bioessays 2020; 42:e1900232. [PMID: 32053231 DOI: 10.1002/bies.201900232] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/10/2020] [Indexed: 12/22/2022]
Abstract
Transposable elements (TEs) are sequences currently or historically mobile, and are present across all eukaryotic genomes. A growing interest in understanding the regulation and function of TEs has revealed seemingly dichotomous roles for these elements in evolution, development, and disease. On the one hand, many gene regulatory networks owe their organization to the spread of cis-elements and DNA binding sites through TE mobilization during evolution. On the other hand, the uncontrolled activity of transposons can generate mutations and contribute to disease, including cancer, while their increased expression may also trigger immune pathways that result in inflammation or senescence. Interestingly, TEs have recently been found to have novel essential functions during mammalian development. Here, the function and regulation of TEs are discussed, with a focus on LINE1 in mammals. It is proposed that LINE1 is a beneficial endogenous dual regulator of gene expression and genomic diversity during mammalian development, and that both of these functions may be detrimental if deregulated in disease contexts.
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Affiliation(s)
- Michelle Percharde
- MRC London Institute of Medical Sciences (LMS), London, W12 0NN, UK.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Tania Sultana
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, M5T 3L9, Ontario, Canada
| | - Miguel Ramalho-Santos
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, M5T 3L9, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, M5S 1A8, Ontario, Canada
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42
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Lou C, Goodier JL, Qiang R. A potential new mechanism for pregnancy loss: considering the role of LINE-1 retrotransposons in early spontaneous miscarriage. Reprod Biol Endocrinol 2020; 18:6. [PMID: 31964400 PMCID: PMC6971995 DOI: 10.1186/s12958-020-0564-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 01/07/2020] [Indexed: 12/14/2022] Open
Abstract
LINE1 retrotransposons are mobile DNA elements that copy and paste themselves into new sites in the genome. To ensure their evolutionary success, heritable new LINE-1 insertions accumulate in cells that can transmit genetic information to the next generation (i.e., germ cells and embryonic stem cells). It is our hypothesis that LINE1 retrotransposons, insertional mutagens that affect expression of genes, may be causal agents of early miscarriage in humans. The cell has evolved various defenses restricting retrotransposition-caused mutation, but these are occasionally relaxed in certain somatic cell types, including those of the early embryo. We predict that reduced suppression of L1s in germ cells or early-stage embryos may lead to excessive genome mutation by retrotransposon insertion, or to the induction of an inflammatory response or apoptosis due to increased expression of L1-derived nucleic acids and proteins, and so disrupt gene function important for embryogenesis. If correct, a novel threat to normal human development is revealed, and reverse transcriptase therapy could be one future strategy for controlling this cause of embryonic damage in patients with recurrent miscarriages.
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Affiliation(s)
- Chao Lou
- Department of Genetics, Northwest Women’s and Children’s Hospital, 1616 Yanxiang Road, Xi’an, Shaanxi Province People’s Republic of China
| | - John L. Goodier
- 0000 0001 2171 9311grid.21107.35McKusick-Nathans Deartment of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Rong Qiang
- Department of Genetics, Northwest Women’s and Children’s Hospital, 1616 Yanxiang Road, Xi’an, Shaanxi Province People’s Republic of China
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43
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Guerrero-Bosagna C. From epigenotype to new genotypes: Relevance of epigenetic mechanisms in the emergence of genomic evolutionary novelty. Semin Cell Dev Biol 2020; 97:86-92. [DOI: 10.1016/j.semcdb.2019.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 07/08/2019] [Accepted: 07/08/2019] [Indexed: 11/24/2022]
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44
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Vazquez BN, Thackray JK, Simonet NG, Chahar S, Kane-Goldsmith N, Newkirk SJ, Lee S, Xing J, Verzi MP, An W, Vaquero A, Tischfield JA, Serrano L. SIRT7 mediates L1 elements transcriptional repression and their association with the nuclear lamina. Nucleic Acids Res 2019; 47:7870-7885. [PMID: 31226208 PMCID: PMC6735864 DOI: 10.1093/nar/gkz519] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/30/2019] [Accepted: 06/03/2019] [Indexed: 02/06/2023] Open
Abstract
Long interspersed elements-1 (LINE-1, L1) are retrotransposons that hold the capacity of self-propagation in the genome with potential mutagenic outcomes. How somatic cells restrict L1 activity and how this process becomes dysfunctional during aging and in cancer cells is poorly understood. L1s are enriched at lamin-associated domains, heterochromatic regions of the nuclear periphery. Whether this association is necessary for their repression has been elusive. Here we show that the sirtuin family member SIRT7 participates in the epigenetic transcriptional repression of L1 genome-wide in both mouse and human cells. SIRT7 depletion leads to increased L1 expression and retrotransposition. Mechanistically, we identify a novel interplay between SIRT7 and Lamin A/C in L1 repression. Our results demonstrate that SIRT7-mediated H3K18 deacetylation regulates L1 expression and promotes L1 association with elements of the nuclear lamina. The failure of such activity might contribute to the observed genome instability and compromised viability in SIRT7 knockout mice. Overall, our results reveal a novel function of SIRT7 on chromatin organization by mediating the anchoring of L1 to the nuclear envelope, and a new functional link of the nuclear lamina with transcriptional repression.
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Affiliation(s)
- Berta N Vazquez
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA.,Chromatin Biology Laboratory, Josep Carreras Leukaemia Research Institute, Badalona, Barcelona 08916, Spain
| | - Joshua K Thackray
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
| | - Nicolas G Simonet
- Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona 08908, Spain
| | - Sanjay Chahar
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA.,Montpellier Institute of Molecular Genetics (IGMM), CNRS and the University of Montpellier, 34090, France
| | - Noriko Kane-Goldsmith
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
| | - Simon J Newkirk
- Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, South Dakota State University, Brookings, SD 57007, USA
| | - Suman Lee
- Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, South Dakota State University, Brookings, SD 57007, USA
| | - Jinchuan Xing
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
| | - Michael P Verzi
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
| | - Wenfeng An
- Department of Pharmaceutical Sciences, College of Pharmacy and Allied Health Professions, South Dakota State University, Brookings, SD 57007, USA
| | - Alejandro Vaquero
- Chromatin Biology Laboratory, Josep Carreras Leukaemia Research Institute, Badalona, Barcelona 08916, Spain.,Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona 08908, Spain
| | - Jay A Tischfield
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
| | - Lourdes Serrano
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ 08854, USA
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45
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piRNA-Guided CRISPR-like Immunity in Eukaryotes. Trends Immunol 2019; 40:998-1010. [DOI: 10.1016/j.it.2019.09.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 09/17/2019] [Accepted: 09/17/2019] [Indexed: 02/07/2023]
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46
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Yang WR, Ardeljan D, Pacyna CN, Payer LM, Burns KH. SQuIRE reveals locus-specific regulation of interspersed repeat expression. Nucleic Acids Res 2019; 47:e27. [PMID: 30624635 PMCID: PMC6411935 DOI: 10.1093/nar/gky1301] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 12/18/2018] [Accepted: 01/03/2019] [Indexed: 12/13/2022] Open
Abstract
Transposable elements (TEs) are interspersed repeat sequences that make up much of the human genome. Their expression has been implicated in development and disease. However, TE-derived RNA-seq reads are difficult to quantify. Past approaches have excluded these reads or aggregated RNA expression to subfamilies shared by similar TE copies, sacrificing quantitative accuracy or the genomic context necessary to understand the basis of TE transcription. As a result, the effects of TEs on gene expression and associated phenotypes are not well understood. Here, we present Software for Quantifying Interspersed Repeat Expression (SQuIRE), the first RNA-seq analysis pipeline that provides a quantitative and locus-specific picture of TE expression (https://github.com/wyang17/SQuIRE). SQuIRE is an accurate and user-friendly tool that can be used for a variety of species. We applied SQuIRE to RNA-seq from normal mouse tissues and a Drosophila model of amyotrophic lateral sclerosis. In both model organisms, we recapitulated previously reported TE subfamily expression levels and revealed locus-specific TE expression. We also identified differences in TE transcription patterns relating to transcript type, gene expression and RNA splicing that would be lost with other approaches using subfamily-level analyses. Altogether, our findings illustrate the importance of studying TE transcription with locus-level resolution.
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Affiliation(s)
- Wan R Yang
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Daniel Ardeljan
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,McKusick-Nathans Institute of Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Clarissa N Pacyna
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Thomas C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD, USA
| | - Lindsay M Payer
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kathleen H Burns
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,McKusick-Nathans Institute of Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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47
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Feusier J, Watkins WS, Thomas J, Farrell A, Witherspoon DJ, Baird L, Ha H, Xing J, Jorde LB. Pedigree-based estimation of human mobile element retrotransposition rates. Genome Res 2019; 29:1567-1577. [PMID: 31575651 PMCID: PMC6771411 DOI: 10.1101/gr.247965.118] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 08/14/2019] [Indexed: 12/26/2022]
Abstract
Germline mutation rates in humans have been estimated for a variety of mutation types, including single-nucleotide and large structural variants. Here, we directly measure the germline retrotransposition rate for the three active retrotransposon elements: L1, Alu, and SVA. We used three tools for calling mobile element insertions (MEIs) (MELT, RUFUS, and TranSurVeyor) on blood-derived whole-genome sequence (WGS) data from 599 CEPH individuals, comprising 33 three-generation pedigrees. We identified 26 de novo MEIs in 437 births. The retrotransposition rate estimates for Alu elements, one in 40 births, is roughly half the rate estimated using phylogenetic analyses, a difference in magnitude similar to that observed for single-nucleotide variants. The L1 retrotransposition rate is one in 63 births and is within range of previous estimates (1:20-1:200 births). The SVA retrotransposition rate, one in 63 births, is much higher than the previous estimate of one in 900 births. Our large, three-generation pedigrees allowed us to assess parent-of-origin effects and the timing of insertion events in either gametogenesis or early embryonic development. We find a statistically significant paternal bias in Alu retrotransposition. Our study represents the first in-depth analysis of the rate and dynamics of human retrotransposition from WGS data in three-generation human pedigrees.
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Affiliation(s)
- Julie Feusier
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - W Scott Watkins
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Jainy Thomas
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Andrew Farrell
- USTAR Center for Genetic Discovery, Salt Lake City, Utah 84112, USA
| | - David J Witherspoon
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Lisa Baird
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Hongseok Ha
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Jinchuan Xing
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
| | - Lynn B Jorde
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
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48
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Abstract
Transposable elements (TEs) are mobile DNA sequences that colonize genomes and threaten genome integrity. As a result, several mechanisms appear to have emerged during eukaryotic evolution to suppress TE activity. However, TEs are ubiquitous and account for a prominent fraction of most eukaryotic genomes. We argue that the evolutionary success of TEs cannot be explained solely by evasion from host control mechanisms. Rather, some TEs have evolved commensal and even mutualistic strategies that mitigate the cost of their propagation. These coevolutionary processes promote the emergence of complex cellular activities, which in turn pave the way for cooption of TE sequences for organismal function.
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Affiliation(s)
- Rachel L Cosby
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Ni-Chen Chang
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
| | - Cédric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
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49
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Zhao Y, Gao N, Li X, El-Ashram S, Wang Z, Zhu L, Jiang W, Peng X, Zhang C, Chen Y, Li Z. Identifying candidate genes associated with sperm morphology abnormalities using weighted single-step GWAS in a Duroc boar population. Theriogenology 2019; 141:9-15. [PMID: 31479777 DOI: 10.1016/j.theriogenology.2019.08.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/23/2019] [Accepted: 08/25/2019] [Indexed: 12/31/2022]
Abstract
Artificial insemination (AI) has been used as a routine technology globally in the pig production industry since 1930. One of the preferable advantages of AI technology is that the semen of elite boars can be disseminated to the commercial sow population rapidly. Understanding the genetic background of semen traits may help in developing genetic improvement programs of boars by including these traits into the selection index. In this study, we utilized weighted single-step genome-wide association study (wssGWAS) to identify genetic regions and further candidate genes associated with sperm morphology abnormalities (proximal droplet, distal droplet, bent tail, coiled tail, and distal midpiece reflex) in a Duroc boar population. Several genomic regions explained 2.76%-9.22% of the genetic variances for sperm morphology abnormalities were identified. The first three detected QTL regions together explained about 7.65%-25.10% of the total genetic variances of the studied traits. Several genes were detected and considered as candidate genes for each of the traits under study: coiled tail, HOOK1, ARSA, SYCE3, SOD3, GMNN, RBPJ, STIL, and FGF1; bent tail, FGF1, ADIPOR1, ARPC5, FGFR3, PANX1, IZUMO1R, ANKRD49, and GAL; proximal droplet, NSF, WNT3, WNT9B, LYZL6, FGFR1OP, RNASET2, FYN, LRRC6, EPC1, DICER1, FNDC3A, and PFN1; distal droplet, ARSA, SYCE3, MOV10L1, CBR1, KDM6B, TP53, PTBP2, UBR7, KIF18A, ADAM15, FAAH, TEKT3, and SRD5A1; and distal midpiece reflex, OMA1, PFN1, PELP1, BMP2, GPR18, TM9SF2, and SPIN1. GO and KEGG enrichment analysis revealed the potential function of the identified candidate genes in spermatogenesis, testis functioning, and boar spermatozoa plasma membrane activating and maintenance. In conclusion, we detected candidate genes associated with the coiled tail, bent tail, proximal droplet, distal droplet, and distal midpiece reflex in a Duroc boar population using wssGWAS. Overall, these novel results reflect the polygenic genetic architecture of the studied sperm morphology abnormality traits, which may provide knowledge for conducting genomic selection on these traits. The detected genetic regions can be used in developing trait-specific marker assisted selection models by assigning higher genetic variances to these regions.
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Affiliation(s)
- Yunxiang Zhao
- College of Life Science and Engineering, Foshan University, 18 Jiangwan Street, Foshan, 528231, Guangdong Province, China; Guangxi Yangxiang Agriculture and Husbandry Co.,LTD, Guigang, 537100, China
| | - Ning Gao
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, North Third Road, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China
| | - Xinyun Li
- Key Laboratory of Agricultural Animal Genetics, Breeding, and Reproduction of the Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Saeed El-Ashram
- College of Life Science and Engineering, Foshan University, 18 Jiangwan Street, Foshan, 528231, Guangdong Province, China
| | - Zhiquan Wang
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Lin Zhu
- Guangxi Yangxiang Agriculture and Husbandry Co.,LTD, Guigang, 537100, China
| | - Wei Jiang
- Guangxi Yangxiang Agriculture and Husbandry Co.,LTD, Guigang, 537100, China
| | - Xing Peng
- Guangxi Yangxiang Agriculture and Husbandry Co.,LTD, Guigang, 537100, China
| | - Conglin Zhang
- Guangxi Yangxiang Agriculture and Husbandry Co.,LTD, Guigang, 537100, China
| | - Yilong Chen
- Key Laboratory of Agricultural Animal Genetics, Breeding, and Reproduction of the Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhili Li
- College of Life Science and Engineering, Foshan University, 18 Jiangwan Street, Foshan, 528231, Guangdong Province, China.
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50
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Saleh A, Macia A, Muotri AR. Transposable Elements, Inflammation, and Neurological Disease. Front Neurol 2019; 10:894. [PMID: 31481926 PMCID: PMC6710400 DOI: 10.3389/fneur.2019.00894] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 08/02/2019] [Indexed: 12/13/2022] Open
Abstract
Transposable Elements (TE) are mobile DNA elements that can replicate and insert themselves into different locations within the host genome. Their propensity to self-propagate has a myriad of consequences and yet their biological significance is not well-understood. Indeed, retrotransposons have evaded evolutionary attempts at repression and may contribute to somatic mosaicism. Retrotransposons are emerging as potent regulatory elements within the human genome. In the diseased state, there is mounting evidence that endogenous retroelements play a role in etiopathogenesis of inflammatory diseases, with a disposition for both autoimmune and neurological disorders. We postulate that active mobile genetic elements contribute more to human disease pathogenesis than previously thought.
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Affiliation(s)
- Aurian Saleh
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
| | - Angela Macia
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
| | - Alysson R Muotri
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
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