1
|
Hwang SY, Kim H, Denisko D, Zhao B, Lee D, Jeong J, Kim J, Park K, Park J, Jeong D, Park S, Choi HJ, Kim S, Lee EA, Ahn K. Human cytomegalovirus harnesses host L1 retrotransposon for efficient replication. Nat Commun 2024; 15:7640. [PMID: 39223139 PMCID: PMC11369119 DOI: 10.1038/s41467-024-51961-y] [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: 12/17/2023] [Accepted: 08/20/2024] [Indexed: 09/04/2024] Open
Abstract
Genetic parasites, including viruses and transposons, exploit components from the host for their own replication. However, little is known about virus-transposon interactions within host cells. Here, we discover a strategy where human cytomegalovirus (HCMV) hijacks L1 retrotransposon encoded protein during its replication cycle. HCMV infection upregulates L1 expression by enhancing both the expression of L1-activating transcription factors, YY1 and RUNX3, and the chromatin accessibility of L1 promoter regions. Increased L1 expression, in turn, promotes HCMV replicative fitness. Affinity proteomics reveals UL44, HCMV DNA polymerase subunit, as the most abundant viral binding protein of the L1 ribonucleoprotein (RNP) complex. UL44 directly interacts with L1 ORF2p, inducing DNA damage responses in replicating HCMV compartments. While increased L1-induced mutagenesis is not observed in HCMV for genetic adaptation, the interplay between UL44 and ORF2p accelerates viral DNA replication by alleviating replication stress. Our findings shed light on how HCMV exploits host retrotransposons for enhanced viral fitness.
Collapse
Affiliation(s)
- Sung-Yeon Hwang
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hyewon Kim
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Danielle Denisko
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Boxun Zhao
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02115, USA
- Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Dohoon Lee
- Bioinformatics Institute, Seoul National University, Seoul, 08826, Republic of Korea
- BK21 FOUR Intelligence Computing, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jiseok Jeong
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jinuk Kim
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kiwon Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Junhyun Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dongjoon Jeong
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sehong Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hee-Jung Choi
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sun Kim
- Department of Computer Science and Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Eunjung Alice Lee
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, 02115, USA.
- Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, 02115, USA.
| | - Kwangseog Ahn
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea.
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea.
| |
Collapse
|
2
|
Potapov V, Krudup S, Maguire S, Unlu I, Guan S, Buss JA, Smail BA, van Eeuwen T, Taylor MS, Burns KH, Ong JL, Trachman RJ. Discrete measurements of RNA polymerase and reverse transcriptase fidelity reveal evolutionary tuning. RNA (NEW YORK, N.Y.) 2024; 30:1246-1258. [PMID: 38942481 PMCID: PMC11331410 DOI: 10.1261/rna.080002.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 06/05/2024] [Indexed: 06/30/2024]
Abstract
Direct methods for determining the fidelity of DNA polymerases are robust, with relatively little sample manipulation before sequencing. In contrast, methods for measuring RNA polymerase and reverse transcriptase fidelities are complicated by additional preparation steps that introduce ambiguity and error. Here, we describe a sequencing method, termed Roll-Seq, for simultaneously determining the individual fidelities of RNA polymerases and reverse transcriptases (RT) using Pacific Biosciences single molecule real-time sequencing. By using reverse transcriptases with high rolling-circle activity, Roll-Seq generates long concatemeric cDNA from a circular RNA template. To discern the origin of a mutation, errors are recorded and determined to occur within a single concatemer (reverse transcriptase error) or all concatemers (RNA polymerase error) over the cDNA strand. We used Roll-Seq to measure the fidelities of T7 RNA polymerases, a Group II intron-encoded RT (Induro), and two LINE RTs (Fasciolopsis buski R2-RT and human LINE-1). Substitution rates for Induro and R2-RT are the same for cDNA and second-strand synthesis while LINE-1 has 2.5-fold lower fidelity when performing second-strand synthesis. Deletion and insertion rates increase for all RTs during second-strand synthesis. In addition, we find that a structured RNA template impacts fidelity for both RNA polymerase and RT. The accuracy and precision of Roll-Seq enable this method to be applied as a complementary analysis to structural and mechanistic characterization of RNA polymerases and reverse transcriptases or as a screening method for RNAP and RT fidelity.
Collapse
Affiliation(s)
| | - Stanislas Krudup
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
- École Supérieure de Biotechnologie de Strasbourg, 67400 Strasbourg, France
| | - Sean Maguire
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Irem Unlu
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Shengxi Guan
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Jackson A Buss
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | - Benedict A Smail
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
| | - Trevor van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York 10065, USA
| | - Martin S Taylor
- Department of Pathology, Mass General Brigham and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Kathleen H Burns
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, USA
- Department of Pathology, Mass General Brigham and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Jennifer L Ong
- New England Biolabs, Inc., Ipswich, Massachusetts 01938, USA
| | | |
Collapse
|
3
|
Palm SM, Horton CA, Zhang X, Collins K. Structure and sequence at an RNA template 5' end influence insertion of transgenes by an R2 retrotransposon protein. RNA (NEW YORK, N.Y.) 2024; 30:1227-1245. [PMID: 38960642 PMCID: PMC11331408 DOI: 10.1261/rna.080031.124] [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: 03/23/2024] [Accepted: 06/17/2024] [Indexed: 07/05/2024]
Abstract
R2 non-long terminal repeat retrotransposons insert site-specifically into ribosomal RNA genes (rDNA) in a broad range of multicellular eukaryotes. R2-encoded proteins can be leveraged to mediate transgene insertion at 28S rDNA loci in cultured human cells. This strategy, precise RNA-mediated insertion of transgenes (PRINT), relies on the codelivery of an mRNA encoding R2 protein and an RNA template encoding a transgene cassette of choice. Here, we demonstrate that the PRINT RNA template 5' module, which as a complementary DNA 3' end will generate the transgene 5' junction with rDNA, influences the efficiency and mechanism of gene insertion. Iterative design and testing identified optimal 5' modules consisting of a hepatitis delta virus-like ribozyme fold with high thermodynamic stability, suggesting that RNA template degradation from its 5' end may limit transgene insertion efficiency. We also demonstrate that transgene 5' junction formation can be either precise, formed by annealing the 3' end of first-strand complementary DNA with the upstream target site, or imprecise, by end-joining, but this difference in junction formation mechanism is not a major determinant of insertion efficiency. Sequence characterization of imprecise end-joining events indicates surprisingly minimal reliance on microhomology. Our findings expand the current understanding of the role of R2 retrotransposon transcript sequence and structure, and especially the 5' ribozyme fold, for retrotransposon mobility and RNA-templated gene synthesis in cells.
Collapse
Affiliation(s)
- Sarah M Palm
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA
| | - Connor A Horton
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA
| | - Xiaozhu Zhang
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA
| | - Kathleen Collins
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA
| |
Collapse
|
4
|
Pozojevic J, Sivaprasad R, Laß J, Haarich F, Trinh J, Kakar N, Schulz K, Händler K, Verrijn Stuart AA, Giltay JC, van Gassen KL, Caliebe A, Holterhus PM, Spielmann M, Hornig NC. LINE1-mediated epigenetic repression of androgen receptor transcription causes androgen insensitivity syndrome. Sci Rep 2024; 14:16302. [PMID: 39009627 PMCID: PMC11251026 DOI: 10.1038/s41598-024-65439-w] [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: 03/11/2024] [Accepted: 06/20/2024] [Indexed: 07/17/2024] Open
Abstract
Androgen insensitivity syndrome (AIS) is a difference of sex development (DSD) characterized by different degrees of undervirilization in individuals with a 46,XY karyotype despite normal to high gonadal testosterone production. Classically, AIS is explained by hemizygous mutations in the X-chromosomal androgen receptor (AR) gene. Nevertheless, the majority of individuals with clinically diagnosed AIS do not carry an AR gene mutation. Here, we present a patient with a 46,XY karyotype, born with undervirilized genitalia, age-appropriate testosterone levels and no uterus, characteristic for AIS. Diagnostic whole exome sequencing (WES) showed a maternally inherited LINE1 (L1) retrotransposon insertion in the 5' untranslated region (5'UTR) of the AR gene. Long-read nanopore sequencing confirmed this as an insertion of a truncated L1 element of ≈ 2.7 kb and showed an increased DNA methylation at the L1 insertion site in patient-derived genital skin fibroblasts (GSFs) compared to healthy controls. The insertion coincided with reduced AR transcript and protein levels in patient-derived GSFs confirming the clinical diagnosis AIS. Our results underline the relevance of retrotransposons in human disease, and expand the growing list of human diseases associated with them.
Collapse
Affiliation(s)
- Jelena Pozojevic
- Institute of Human Genetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany.
| | - Radhika Sivaprasad
- Institute of Human Genetics, University of Kiel and University Hospital Schleswig-Holstein, Kiel, Germany
| | - Joshua Laß
- Institute of Neurogenetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Franziska Haarich
- Institute of Cardiogenetics, University of Lübeck and German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Lübeck/Kiel, Lübeck, Germany
| | - Joanne Trinh
- Institute of Neurogenetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Naseebullah Kakar
- Institute of Human Genetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
- Department of Biotechnology, FLS&I, BUITEMS, Quetta, Pakistan
| | - Kristin Schulz
- Institute of Human Genetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Kristian Händler
- Institute of Human Genetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Annemarie A Verrijn Stuart
- Department of Pediatric Endocrinology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jacques C Giltay
- Division Laboratories, Pharmacy and Biomedical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Koen L van Gassen
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Almuth Caliebe
- Institute of Human Genetics, University of Kiel and University Hospital Schleswig-Holstein, Kiel, Germany
| | - Paul-Martin Holterhus
- Division of Paediatric Endocrinology and Diabetes, Department of Paediatrics, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Malte Spielmann
- Institute of Human Genetics, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
- Institute of Human Genetics, University of Kiel and University Hospital Schleswig-Holstein, Kiel, Germany
- Human Molecular Genomics Group, Max Planck Institute for Molecular Genetics, Berlin, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Lübeck/Kiel, Lübeck, Germany
| | - Nadine C Hornig
- Institute of Human Genetics, University of Kiel and University Hospital Schleswig-Holstein, Kiel, Germany.
| |
Collapse
|
5
|
Lee RJ, Horton CA, Van Treeck B, McIntyre JJR, Collins K. Conserved and divergent DNA recognition specificities and functions of R2 retrotransposon N-terminal domains. Cell Rep 2024; 43:114239. [PMID: 38753487 PMCID: PMC11204384 DOI: 10.1016/j.celrep.2024.114239] [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: 01/24/2024] [Revised: 04/04/2024] [Accepted: 05/01/2024] [Indexed: 05/18/2024] Open
Abstract
R2 non-long terminal repeat (non-LTR) retrotransposons are among the most extensively distributed mobile genetic elements in multicellular eukaryotes and show promise for applications in transgene supplementation of the human genome. They insert new gene copies into a conserved site in 28S ribosomal DNA with exquisite specificity. R2 clades are defined by the number of zinc fingers (ZFs) at the N terminus of the retrotransposon-encoded protein, postulated to additively confer DNA site specificity. Here, we illuminate general principles of DNA recognition by R2 N-terminal domains across and between clades, with extensive, specific recognition requiring only one or two compact domains. DNA-binding and protection assays demonstrate broadly shared as well as clade-specific DNA interactions. Gene insertion assays in cells identify the N-terminal domains sufficient for target-site insertion and reveal roles in second-strand cleavage or synthesis for clade-specific ZFs. Our results have implications for understanding evolutionary diversification of non-LTR retrotransposon insertion mechanisms and the design of retrotransposon-based gene therapies.
Collapse
Affiliation(s)
- Rosa Jooyoung Lee
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Connor A Horton
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Briana Van Treeck
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Jeremy J R McIntyre
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Kathleen Collins
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
6
|
Baldwin ET, van Eeuwen T, Hoyos D, Zalevsky A, Tchesnokov EP, Sánchez R, Miller BD, Di Stefano LH, Ruiz FX, Hancock M, Işik E, Mendez-Dorantes C, Walpole T, Nichols C, Wan P, Riento K, Halls-Kass R, Augustin M, Lammens A, Jestel A, Upla P, Xibinaku K, Congreve S, Hennink M, Rogala KB, Schneider AM, Fairman JE, Christensen SM, Desrosiers B, Bisacchi GS, Saunders OL, Hafeez N, Miao W, Kapeller R, Zaller DM, Sali A, Weichenrieder O, Burns KH, Götte M, Rout MP, Arnold E, Greenbaum BD, Romero DL, LaCava J, Taylor MS. Structures, functions and adaptations of the human LINE-1 ORF2 protein. Nature 2024; 626:194-206. [PMID: 38096902 PMCID: PMC10830420 DOI: 10.1038/s41586-023-06947-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024]
Abstract
The LINE-1 (L1) retrotransposon is an ancient genetic parasite that has written around one-third of the human genome through a 'copy and paste' mechanism catalysed by its multifunctional enzyme, open reading frame 2 protein (ORF2p)1. ORF2p reverse transcriptase (RT) and endonuclease activities have been implicated in the pathophysiology of cancer2,3, autoimmunity4,5 and ageing6,7, making ORF2p a potential therapeutic target. However, a lack of structural and mechanistic knowledge has hampered efforts to rationally exploit it. We report structures of the human ORF2p 'core' (residues 238-1061, including the RT domain) by X-ray crystallography and cryo-electron microscopy in several conformational states. Our analyses identified two previously undescribed folded domains, extensive contacts to RNA templates and associated adaptations that contribute to unique aspects of the L1 replication cycle. Computed integrative structural models of full-length ORF2p show a dynamic closed-ring conformation that appears to open during retrotransposition. We characterize ORF2p RT inhibition and reveal its underlying structural basis. Imaging and biochemistry show that non-canonical cytosolic ORF2p RT activity can produce RNA:DNA hybrids, activating innate immune signalling through cGAS/STING and resulting in interferon production6-8. In contrast to retroviral RTs, L1 RT is efficiently primed by short RNAs and hairpins, which probably explains cytosolic priming. Other biochemical activities including processivity, DNA-directed polymerization, non-templated base addition and template switching together allow us to propose a revised L1 insertion model. Finally, our evolutionary analysis demonstrates structural conservation between ORF2p and other RNA- and DNA-dependent polymerases. We therefore provide key mechanistic insights into L1 polymerization and insertion, shed light on the evolutionary history of L1 and enable rational drug development targeting L1.
Collapse
Affiliation(s)
| | - Trevor van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | - David Hoyos
- Computational Oncology, Department of Epidemiology & Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Arthur Zalevsky
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Egor P Tchesnokov
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Bryant D Miller
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Luciano H Di Stefano
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, The Netherlands
| | - Francesc Xavier Ruiz
- Center for Advanced Biotechnology and Medicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA
| | - Matthew Hancock
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Esin Işik
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Carlos Mendez-Dorantes
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Thomas Walpole
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Charles Nichols
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Paul Wan
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Kirsi Riento
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | - Rowan Halls-Kass
- Charles River Laboratories, Chesterford Research Park, Saffron Walden, UK
| | | | - Alfred Lammens
- Proteros Biostructures GmbH, Martinsried, Planegg, Germany
| | - Anja Jestel
- Proteros Biostructures GmbH, Martinsried, Planegg, Germany
| | - Paula Upla
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | - Kera Xibinaku
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | | | - Kacper B Rogala
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Anna M Schneider
- Structural Biology of Selfish RNA, Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | | | | | | | | | | | | | | | | | | | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
- Quantitative Biology Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Oliver Weichenrieder
- Structural Biology of Selfish RNA, Department of Protein Evolution, Max Planck Institute for Biology, Tübingen, Germany
| | - Kathleen H Burns
- Department of Pathology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, USA.
| | - Matthias Götte
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA.
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA.
| | - Benjamin D Greenbaum
- Computational Oncology, Department of Epidemiology & Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Physiology, Biophysics & Systems Biology, Weill Cornell Medicine, Weill Cornell Medical College, New York, NY, USA.
| | | | - John LaCava
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA.
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, The Netherlands.
| | - Martin S Taylor
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
7
|
Warkocki Z. An update on post-transcriptional regulation of retrotransposons. FEBS Lett 2023; 597:380-406. [PMID: 36460901 DOI: 10.1002/1873-3468.14551] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 11/09/2022] [Accepted: 11/18/2022] [Indexed: 12/04/2022]
Abstract
Retrotransposons, including LINE-1, Alu, SVA, and endogenous retroviruses, are one of the major constituents of human genomic repetitive sequences. Through the process of retrotransposition, some of them occasionally insert into new genomic locations by a copy-paste mechanism involving RNA intermediates. Irrespective of de novo genomic insertions, retrotransposon expression can lead to DNA double-strand breaks and stimulate cellular innate immunity through endogenous patterns. As a result, retrotransposons are tightly regulated by multi-layered regulatory processes to prevent the dangerous effects of their expression. In recent years, significant progress was made in revealing how retrotransposon biology intertwines with general post-transcriptional RNA metabolism. Here, I summarize current knowledge on the involvement of post-transcriptional factors in the biology of retrotransposons, focusing on LINE-1. I emphasize general RNA metabolisms such as methylation of adenine (m6 A), RNA 3'-end polyadenylation and uridylation, RNA decay and translation regulation. I discuss the effects of retrotransposon RNP sequestration in cytoplasmic bodies and autophagy. Finally, I summarize how innate immunity restricts retrotransposons and how retrotransposons make use of cellular enzymes, including the DNA repair machinery, to complete their replication cycles.
Collapse
Affiliation(s)
- Zbigniew Warkocki
- Department of RNA Metabolism, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| |
Collapse
|
8
|
Gasparotto E, Burattin FV, Di Gioia V, Panepuccia M, Ranzani V, Marasca F, Bodega B. Transposable Elements Co-Option in Genome Evolution and Gene Regulation. Int J Mol Sci 2023; 24:ijms24032610. [PMID: 36768929 PMCID: PMC9917352 DOI: 10.3390/ijms24032610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/26/2023] [Accepted: 01/28/2023] [Indexed: 01/31/2023] Open
Abstract
The genome is no longer deemed as a fixed and inert item but rather as a moldable matter that is continuously evolving and adapting. Within this frame, Transposable Elements (TEs), ubiquitous, mobile, repetitive elements, are considered an alive portion of the genomes to date, whose functions, although long considered "dark", are now coming to light. Here we will review that, besides the detrimental effects that TE mobilization can induce, TEs have shaped genomes in their current form, promoting genome sizing, genomic rearrangements and shuffling of DNA sequences. Although TEs are mostly represented in the genomes by evolutionarily old, short, degenerated, and sedentary fossils, they have been thoroughly co-opted by the hosts as a prolific and original source of regulatory instruments for the control of gene transcription and genome organization in the nuclear space. For these reasons, the deregulation of TE expression and/or activity is implicated in the onset and progression of several diseases. It is likely that we have just revealed the outermost layers of TE functions. Further studies on this portion of the genome are required to unlock novel regulatory functions that could also be exploited for diagnostic and therapeutic approaches.
Collapse
Affiliation(s)
- Erica Gasparotto
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
- SEMM, European School of Molecular Medicine, 20139 Milan, Italy
| | - Filippo Vittorio Burattin
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
- Department of Biosciences, University of Milan, 20133 Milan, Italy
| | - Valeria Di Gioia
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
- SEMM, European School of Molecular Medicine, 20139 Milan, Italy
| | - Michele Panepuccia
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
| | - Valeria Ranzani
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
| | - Federica Marasca
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy
| | - Beatrice Bodega
- Fondazione INGM, Istituto Nazionale di Genetica Molecolare “Enrica e Romeo Invernizzi”, 20122 Milan, Italy
- Department of Biosciences, University of Milan, 20133 Milan, Italy
- Correspondence:
| |
Collapse
|
9
|
Kaur D, Agrahari M, Bhattacharya A, Bhattacharya S. The non-LTR retrotransposons of Entamoeba histolytica: genomic organization and biology. Mol Genet Genomics 2022; 297:1-18. [PMID: 34999963 DOI: 10.1007/s00438-021-01843-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 11/26/2021] [Indexed: 11/24/2022]
Abstract
Genome sequence analysis of Entamoeba species revealed various classes of transposable elements. While E. histolytica and E. dispar are rich in non-long terminal repeat (LTR) retrotransposons, E. invadens contains predominantly DNA transposons. Non-LTR retrotransposons of E. histolytica constitute three families of long interspersed nuclear elements (LINEs), and their short, nonautonomous partners, SINEs. They occupy ~ 11% of the genome. The EhLINE1/EhSINE1 family is the most abundant and best studied. EhLINE1 is 4.8 kb, with two ORFs that encode functions needed for retrotransposition. ORF1 codes for the nucleic acid-binding protein, and ORF2 has domains for reverse transcriptase (RT) and endonuclease (EN). Most copies of EhLINEs lack complete ORFs. ORF1p is expressed constitutively, but ORF2p is not detected. Retrotransposition could be demonstrated upon ectopic over expression of ORF2p, showing that retrotransposition machinery is functional. The newly retrotransposed sequences showed a high degree of recombination. In transcriptomic analysis, RNA-Seq reads were mapped to individual EhLINE1 copies. Although full-length copies were transcribed, no full-length 4.8 kb transcripts were seen. Rather, sense transcripts mapped to ORF1, RT and EN domains. Intriguingly, there was strong antisense transcription almost exclusively from the RT domain. These unique features of EhLINE1 could serve to attenuate retrotransposition in E. histolytica.
Collapse
|
10
|
Liu G, Jiang H, Sun W, Zhang J, Chen D, Murchie AIH. The function of twister ribozyme variants in non-LTR retrotransposition in Schistosoma mansoni. Nucleic Acids Res 2021; 49:10573-10588. [PMID: 34551436 PMCID: PMC8501958 DOI: 10.1093/nar/gkab818] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/23/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022] Open
Abstract
The twister ribozyme is widely distributed over numerous organisms and is especially abundant in Schistosoma mansoni, but has no confirmed biological function. Of the 17 non-LTR retrotransposons known in S. mansoni, none have thus far been associated with ribozymes. Here we report the identification of novel twister variant (T-variant) ribozymes and their function in S. mansoni non-LTR retrotransposition. We show that T-variant ribozymes are located at the 5′ end of Perere-3 non-LTR retrotransposons in the S. mansoni genome. T-variant ribozymes were demonstrated to be catalytically active in vitro. In reporter constructs, T-variants were shown to cleave in vivo, and cleavage of T-variants was sufficient for the translation of downstream reporter genes. Our analysis shows that the T-variants and Perere-3 are transcribed together. Target site duplications (TSDs); markers of target-primed reverse transcription (TPRT) and footmarks of retrotransposition, are located adjacent to the T-variant cleavage site and suggest that T-variant cleavage has taken place inS. mansoni. Sequence heterogeneity in the TSDs indicates that Perere-3 retrotransposition is not site-specific. The TSD sequences contribute to the 5′ end of the terminal ribozyme helix (P1 stem). Based on these results we conclude that T-variants have a functional role in Perere-3 retrotransposition.
Collapse
Affiliation(s)
- Getong Liu
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Hengyi Jiang
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Wenxia Sun
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Jun Zhang
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Dongrong Chen
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Alastair I H Murchie
- Fudan University Pudong Medical Center, and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| |
Collapse
|
11
|
Kaur D, Agrahari M, Singh SS, Mandal PK, Bhattacharya A, Bhattacharya S. Transcriptomic analysis of Entamoeba histolytica reveals domain-specific sense strand expression of LINE-encoded ORFs with massive antisense expression of RT domain. Plasmid 2021; 114:102560. [PMID: 33482228 DOI: 10.1016/j.plasmid.2021.102560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 11/29/2022]
Abstract
LINEs are retrotransposable elements found in diverse organisms. Their activity is kept in check by several mechanisms, including transcriptional silencing. Here we have analyzed the transcription status of LINE1 copies in the early-branching parasitic protist Entamoeba histolytica. Full-length EhLINE1 encodes ORF1, and ORF2 with reverse transcriptase (RT) and endonuclease (EN) domains. RNA-Seq analysis of EhLINE1 copies (both truncated and full-length) showed unique features. Firstly, although 20/41 transcribed copies were full-length, we failed to detect any full-length transcripts. Rather, sense-strand transcripts mapped to the functional domains- ORF1, RT and EN. Secondly, there was strong antisense transcription specifically from RT domain. No antisense transcripts were seen from ORF1. Antisense RT transcripts did not encode known functional peptides. They could possibly be involved in attenuating translation of RT domain, as we failed to detect ORF2p, whereas ORF1p was detectable. Lack of full-length transcripts and strong antisense RT expression may serve to limit EhLINE1 retrotransposition.
Collapse
Affiliation(s)
- Devinder Kaur
- School of Environmental Sciences, Jawaharlal Nehru University, India
| | - Mridula Agrahari
- School of Environmental Sciences, Jawaharlal Nehru University, India
| | | | | | | | | |
Collapse
|
12
|
Pradhan M, Govindaraju A, Jagdish A, Christensen SM. The linker region of LINEs modulates DNA cleavage and DNA polymerization. Anal Biochem 2020; 603:113809. [PMID: 32511965 DOI: 10.1016/j.ab.2020.113809] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 01/09/2023]
Abstract
Long interspersed elements (LINEs) replicate by target primed reverse transcription (TPRT). Insertion involves two half reactions. Each half reaction involves DNA cleavage followed by DNA synthesis. The linker region, located just beyond the reverse transcriptase in the LINE open reading frame, contains a set of predicted helices that may form an α-finger, followed by a gag-like zinc-knuckle. Point mutations of moderately conserved amino-acid residues in the presumptive α-finger severely impair the DNA endonuclease and reverse transcriptase activities of the integration reaction during both half reactions. Mutations in the gag-like zinc-knuckle also impair DNA cleavage and DNA synthesis in some instances. Mutations in core residues that presumably disrupt the protein structure of the presumptive α-finger and the gag-like zinc-knuckle lead to a promiscuous DNA endonuclease and protein-nucleic acid complexes that get stuck in the well during analysis. The linker region appears to function as a protein, DNA, and RNA conformational switching area. The linker is used to properly position nucleic acid substrates into the active sites of the reverse transcriptase and of the DNA endonuclease.
Collapse
Affiliation(s)
- Monika Pradhan
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Aruna Govindaraju
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Athena Jagdish
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Shawn M Christensen
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA.
| |
Collapse
|
13
|
Markova DN, Christensen SM, Betrán E. Telomere-Specialized Retroelements in Drosophila: Adaptive Symbionts of the Genome, Neutral, or in Conflict? Bioessays 2019; 42:e1900154. [PMID: 31815300 DOI: 10.1002/bies.201900154] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/31/2019] [Indexed: 12/17/2022]
Abstract
Linear chromosomes shorten in every round of replication. In Drosophila, telomere-specialized long interspersed retrotransposable elements (LINEs) belonging to the jockey clade offset this shortening by forming head-to-tail arrays at Drosophila telomere ends. As such, these telomeric LINEs have been considered adaptive symbionts of the genome, protecting it from premature decay, particularly as Drosophila lacks a conventional telomerase holoenzyme. However, as reviewed here, recent work reveals a high degree of variation and turnover in the telomere-specialized LINE lineages across Drosophila. There appears to be no absolute requirement for LINE activity to maintain telomeres in flies, hence the suggestion that the telomere-specialized LINEs may instead be neutral or in conflict with the host, rather than adaptive.
Collapse
Affiliation(s)
- Dragomira N Markova
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Shawn M Christensen
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Esther Betrán
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| |
Collapse
|
14
|
Lentzsch AM, Yao J, Russell R, Lambowitz AM. Template-switching mechanism of a group II intron-encoded reverse transcriptase and its implications for biological function and RNA-Seq. J Biol Chem 2019; 294:19764-19784. [PMID: 31712313 DOI: 10.1074/jbc.ra119.011337] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/01/2019] [Indexed: 12/18/2022] Open
Abstract
The reverse transcriptases (RTs) encoded by mobile group II introns and other non-LTR retroelements differ from retroviral RTs in being able to template-switch efficiently from the 5' end of one template to the 3' end of another with little or no complementarity between the donor and acceptor templates. Here, to establish a complete kinetic framework for the reaction and to identify conditions that more efficiently capture acceptor RNAs or DNAs, we used a thermostable group II intron RT (TGIRT; GsI-IIC RT) that can template switch directly from synthetic RNA template/DNA primer duplexes having either a blunt end or a 3'-DNA overhang end. We found that the rate and amplitude of template switching are optimal from starter duplexes with a single nucleotide 3'-DNA overhang complementary to the 3' nucleotide of the acceptor RNA, suggesting a role for nontemplated nucleotide addition of a complementary nucleotide to the 3' end of cDNAs synthesized from natural templates. Longer 3'-DNA overhangs progressively decreased the template-switching rate, even when complementary to the 3' end of the acceptor template. The reliance on only a single bp with the 3' nucleotide of the acceptor together with discrimination against mismatches and the high processivity of group II intron RTs enable synthesis of full-length DNA copies of nucleic acids beginning directly at their 3' end. We discuss the possible biological functions of the template-switching activity of group II intron- and other non-LTR retroelement-encoded RTs, as well as the optimization of this activity for adapter addition in RNA- and DNA-Seq protocols.
Collapse
Affiliation(s)
- Alfred M Lentzsch
- Institute for Cellular and Molecular Biology, Departments of Molecular Biosciences and Oncology, University of Texas at Austin, Austin, Texas 78712
| | - Jun Yao
- Institute for Cellular and Molecular Biology, Departments of Molecular Biosciences and Oncology, University of Texas at Austin, Austin, Texas 78712
| | - Rick Russell
- Institute for Cellular and Molecular Biology, Departments of Molecular Biosciences and Oncology, University of Texas at Austin, Austin, Texas 78712
| | - Alan M Lambowitz
- Institute for Cellular and Molecular Biology, Departments of Molecular Biosciences and Oncology, University of Texas at Austin, Austin, Texas 78712
| |
Collapse
|