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Boroumand-Noughabi S, Pashaee A, Montazer M, Rahmati A, Ayatollahi H, Sadeghian MH, Keramati MR. Investigating the Expression Pattern of the SETMAR Gene Transcript Variants in Childhood Acute Leukemia: Revisiting an Old Gene. J Pediatr Hematol Oncol 2023; 45:e603-e608. [PMID: 36706314 DOI: 10.1097/mph.0000000000002624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 11/20/2022] [Indexed: 01/29/2023]
Abstract
BACKGROUND The chimeric enzyme SETMAR (or Metnase) has been associated with several DNA processes, including DNA damage repair through the non-homologous joining pathway and suppression of chromosomal translocation in mouse fibroblasts. SETMAR overexpression has been reported in certain cancers suggesting that it might contribute to the establishment or progression of these cancers. In leukemia, the SETMAR gene transcript variants have not been widely studied. Therefore, this study aimed to quantify 3 predominant SETMAR variants in 2 types of childhood acute leukemia, acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). METHODS In this study, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), the relative expression of 3 SETMAR transcript variants (Var 1, Var 2, and Var A) were evaluated in the bone marrow samples collected from 30 newly diagnosed patients with AML, 65 newly diagnosed patients with ALL, and 15 healthy individuals. RESULTS The expression of SETMAR variants 1 and A were significantly higher in AML patients compared with controls ( P =0.02, and P =0.009, respectively). Variant A expression was significantly higher in ALL compared with controls ( P =0.003). When comparing the expression in translocation-positive and negative subgroups, the expression of variant 1 was significantly higher in translocation-positive ALL patients ( P =0.03). The variants' distribution patterns differed concerning translocation status ( P =0.041), as variants 1 and A were dominant in the translocation-positive ALL group, and variant 2 was more prevalent in translocation-negative ones. CONCLUSIONS According to the results, SETMAR showed increased expression in pediatric acute leukemia's bone marrow samples, indicating a role for this molecule in leukemia pathogenesis. As this is the first report of SETMAR expression in pediatric leukemias, further studies are needed to investigate the causality of this association.
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Affiliation(s)
- Samaneh Boroumand-Noughabi
- Department of Hematology and Blood Banking
- Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad
| | | | | | - Atefe Rahmati
- Department of Hematology and Blood Banking
- Department of Basic Medical Sciences, Faculty of Medicine, Neyshabur University of Medical Sciences, Neyshabur, Iran
| | - Hossein Ayatollahi
- Department of Hematology and Blood Banking
- Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad
| | - Mohammad Hadi Sadeghian
- Department of Hematology and Blood Banking
- Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad
| | - Mohammad Reza Keramati
- Department of Hematology and Blood Banking
- Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad
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Xu Y, Wang H, Sahu SK, Li L, Liang H, Günther G, Wong GKS, Melkonian B, Melkonian M, Liu H, Wang S. Chromosome-level genome of Pedinomonas minor (Chlorophyta) unveils adaptations to abiotic stress in a rapidly fluctuating environment. THE NEW PHYTOLOGIST 2022; 235:1409-1425. [PMID: 35560066 DOI: 10.1111/nph.18220] [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: 03/14/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
The Pedinophyceae (Viridiplantae) comprise a class of small uniflagellate algae with a pivotal position in the phylogeny of the Chlorophyta as the sister group of the 'core chlorophytes'. We present a chromosome-level genome assembly of the freshwater type species of the class, Pedinomonas minor. We sequenced the genome using Pacbio, Illumina and Hi-C technologies, performed comparative analyses of genome and gene family evolution, and analyzed the transcriptome under various abiotic stresses. Although the genome is relatively small (55 Mb), it shares many traits with core chlorophytes including number of introns and protein-coding genes, messenger RNA (mRNA) lengths, and abundance of transposable elements. Pedinomonas minor is only bounded by the plasma membrane, thriving in temporary habitats that frequently dry out. Gene family innovations and expansions and transcriptomic responses to abiotic stresses have shed light on adaptations of P. minor to its fluctuating environment. Horizontal gene transfers from bacteria and fungi have possibly contributed to the evolution of some of these traits. We identified a putative endogenization site of a nucleocytoplasmic large DNA virus and hypothesized that endogenous viral elements donated foreign genes to the host genome, their spread enhanced by transposable elements, located at gene boundaries in several of the expanded gene families.
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Affiliation(s)
- Yan Xu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Hongli Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Sunil Kumar Sahu
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Linzhou Li
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, 2800, Denmark
| | - Hongping Liang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Gerd Günther
- Private Laboratory, Knittkuhler Str. 61, Düsseldorf, 40629, Germany
| | - Gane Ka-Shu Wong
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
- Department of Medicine, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Barbara Melkonian
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
| | - Michael Melkonian
- Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, 50829, Germany
| | - Huan Liu
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 10049, China
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Sibo Wang
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, 518083, China
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A novel transposable element-mediated mechanism causes antiviral resistance in Drosophila through truncating the Veneno protein. Proc Natl Acad Sci U S A 2022; 119:e2122026119. [PMID: 35858337 PMCID: PMC9304006 DOI: 10.1073/pnas.2122026119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Hosts are continually selected to evolve new defenses against an ever-changing array of pathogens. To understand this process, we examined the genetic basis of resistance to the Drosophila A virus in Drosophila melanogaster. In a natural population, we identified a polymorphic transposable element (TE) insertion that was associated with an ∼19,000-fold reduction in viral titers, allowing flies to largely escape the harmful effects of infection by this virulent pathogen. The insertion occurs in the protein-coding sequence of the gene Veneno, which encodes a Tudor domain protein. By mutating Veneno with CRISPR-Cas9 in flies and expressing it in cultured cells, we show that the ancestral allele of the gene has no effect on viral replication. Instead, the TE insertion is a gain-of-function mutation that creates a gene encoding a novel resistance factor. Viral titers remained reduced when we deleted the TE sequence from the transcript, indicating that resistance results from the TE truncating the Veneno protein. This is a novel mechanism of virus resistance and a new way by which TEs can contribute to adaptation.
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Fueyo R, Judd J, Feschotte C, Wysocka J. Roles of transposable elements in the regulation of mammalian transcription. Nat Rev Mol Cell Biol 2022; 23:481-497. [PMID: 35228718 PMCID: PMC10470143 DOI: 10.1038/s41580-022-00457-y] [Citation(s) in RCA: 104] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2022] [Indexed: 12/16/2022]
Abstract
Transposable elements (TEs) comprise about half of the mammalian genome. TEs often contain sequences capable of recruiting the host transcription machinery, which they use to express their own products and promote transposition. However, the regulatory sequences carried by TEs may affect host transcription long after the TEs have lost the ability to transpose. Recent advances in genome analysis and engineering have facilitated systematic interrogation of the regulatory activities of TEs. In this Review, we discuss diverse mechanisms by which TEs contribute to transcription regulation. Notably, TEs can donate enhancer and promoter sequences that influence the expression of host genes, modify 3D chromatin architecture and give rise to novel regulatory genes, including non-coding RNAs and transcription factors. We discuss how TEs spur regulatory evolution and facilitate the emergence of genetic novelties in mammalian physiology and development. By virtue of their repetitive and interspersed nature, TEs offer unique opportunities to dissect the effects of mutation and genomic context on the function and evolution of cis-regulatory elements. We argue that TE-centric studies hold the key to unlocking general principles of transcription regulation and evolution.
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Affiliation(s)
- Raquel Fueyo
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Julius Judd
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Cedric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
| | - Joanna Wysocka
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, USA.
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA.
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA.
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Lié O, Renault S, Augé-Gouillou C. SETMAR, a case of primate co-opted genes: towards new perspectives. Mob DNA 2022; 13:9. [PMID: 35395947 PMCID: PMC8994322 DOI: 10.1186/s13100-022-00267-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 03/28/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We carry out a review of the history and biological activities of one domesticated gene in higher primates, SETMAR, by discussing current controversies. Our purpose is to open a new outlook that will serve as a framework for future work about SETMAR, possibly in the field of cognition development. MAIN BODY What is newly important about SETMAR can be summarized as follows: (1) the whole protein sequence is under strong purifying pressure; (2) its role is to strengthen existing biological functions rather than to provide new ones; (3) it displays a tissue-specific pattern of expression, at least for the alternative-splicing it undergoes. Studies reported here demonstrate that SETMAR protein(s) may be involved in essential networks regulating replication, transcription and translation. Moreover, during embryogenesis, SETMAR appears to contribute to brain development. SHORT CONCLUSION Our review underlines for the first time that SETMAR directly interacts with genes involved in brain functions related to vocalization and vocal learning. These findings pave the way for future works regarding SETMAR and the development of cognitive abilities in higher primates.
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Affiliation(s)
- Oriane Lié
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France
| | - Sylvaine Renault
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France
| | - Corinne Augé-Gouillou
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France. .,iBrain, Team Neurogenomics and Neuronal physiopathology, Faculty of Medicine, 10 Bd Tonnellé, Cedex 1, 37032, Tours, France.
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Structural and genome-wide analyses suggest that transposon-derived protein SETMAR alters transcription and splicing. J Biol Chem 2022; 298:101894. [PMID: 35378129 PMCID: PMC9062482 DOI: 10.1016/j.jbc.2022.101894] [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: 12/18/2021] [Revised: 03/25/2022] [Accepted: 03/26/2022] [Indexed: 11/22/2022] Open
Abstract
Extensive portions of the human genome have unknown function, including those derived from transposable elements. One such element, the DNA transposon Hsmar1, entered the primate lineage approximately 50 million years ago leaving behind terminal inverted repeat (TIR) sequences and a single intact copy of the Hsmar1 transposase, which retains its ancestral TIR-DNA-binding activity, and is fused with a lysine methyltransferase SET domain to constitute the chimeric SETMAR gene. Here, we provide a structural basis for recognition of TIRs by SETMAR and investigate the function of SETMAR through genome-wide approaches. As elucidated in our 2.37 Å crystal structure, SETMAR forms a dimeric complex with each DNA-binding domain bound specifically to TIR-DNA through the formation of 32 hydrogen bonds. We found that SETMAR recognizes primarily TIR sequences (∼5000 sites) within the human genome as assessed by chromatin immunoprecipitation sequencing analysis. In two SETMAR KO cell lines, we identified 163 shared differentially expressed genes and 233 shared alternative splicing events. Among these genes are several pre–mRNA-splicing factors, transcription factors, and genes associated with neuronal function, and one alternatively spliced primate-specific gene, TMEM14B, which has been identified as a marker for neocortex expansion associated with brain evolution. Taken together, our results suggest a model in which SETMAR impacts differential expression and alternative splicing of genes associated with transcription and neuronal function, potentially through both its TIR-specific DNA-binding and lysine methyltransferase activities, consistent with a role for SETMAR in simian primate development.
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Almeida MV, Vernaz G, Putman AL, Miska EA. Taming transposable elements in vertebrates: from epigenetic silencing to domestication. Trends Genet 2022; 38:529-553. [DOI: 10.1016/j.tig.2022.02.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 02/14/2022] [Accepted: 02/15/2022] [Indexed: 12/20/2022]
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Lié O, Virolle T, Gabut M, Pasquier C, Zemmoura I, Augé-Gouillou C. SETMAR Shorter Isoform: A New Prognostic Factor in Glioblastoma. Front Oncol 2022; 11:638397. [PMID: 35047379 PMCID: PMC8761672 DOI: 10.3389/fonc.2021.638397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 11/03/2021] [Indexed: 12/27/2022] Open
Abstract
Recent evidence suggests that the chimeric protein SETMAR is a factor of interest in cancer, especially in glioblastoma. However, little is known about the expression of this protein in glioblastoma tissues, and no study has been done to assess if SETMAR could be a prognostic and/or diagnostic marker of glioblastoma. We analyzed protein extracts of 47 glioblastoma samples coming from a local and a national cohort of patients. From the local cohort, we obtained localized biopsies from the central necrosis area, the tumor, and the perilesional brain. From the French Glioblastoma Biobank (FGB), we obtained three types of samples: from the same tumors before and after treatment, from long survivors, and from very short survivors. We studied the correlations between SETMAR amounts, clinical profiles of patients and other associated proteins (PTN, snRNP70 and OLIG2). In glioblastoma tissues, the shorter isoform of SETMAR (S-SETMAR) was predominant over the full-length isoform (FL-SETMAR), and the expression of both SETMAR variants was higher in the tumor compared to the perilesional tissues. Data from the FGB showed that SETMAR amounts were not different between the initial tumors and tumor relapses after treatment. These data also showed a trend toward higher amounts of S-SETMAR in long survivors. In localized biopsies, we found a positive correlation between good prognosis and large amounts of S-SETMAR in the perilesional area. This is the main result presented here: survival in Glioblastoma is correlated with amounts of S-SETMAR in perilesional brain, which should be considered as a new relevant prognosis marker.
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Affiliation(s)
- Oriane Lié
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
| | - Thierry Virolle
- Institut de Biologie Valrose, Université Côte D’Azur, CNRS, INSERM, Nice, France
| | - Mathieu Gabut
- INSERM 1052, CNRS 5286, Cancer Research Center of Lyon, Centre Léon Bérard, Lyon, France
- Université Claude Bernard Lyon 1, Villeurbanne, France
| | | | - Ilyess Zemmoura
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France
- Service de Neurochirurgie, CHRU de Tours, Tours, France
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9
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Tellier M. Structure, Activity, and Function of SETMAR Protein Lysine Methyltransferase. Life (Basel) 2021; 11:life11121342. [PMID: 34947873 PMCID: PMC8704517 DOI: 10.3390/life11121342] [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: 11/09/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 12/21/2022] Open
Abstract
SETMAR is a protein lysine methyltransferase that is involved in several DNA processes, including DNA repair via the non-homologous end joining (NHEJ) pathway, regulation of gene expression, illegitimate DNA integration, and DNA decatenation. However, SETMAR is an atypical protein lysine methyltransferase since in anthropoid primates, the SET domain is fused to an inactive DNA transposase. The presence of the DNA transposase domain confers to SETMAR a DNA binding activity towards the remnants of its transposable element, which has resulted in the emergence of a gene regulatory function. Both the SET and the DNA transposase domains are involved in the different cellular roles of SETMAR, indicating the presence of novel and specific functions in anthropoid primates. In addition, SETMAR is dysregulated in different types of cancer, indicating a potential pathological role. While some light has been shed on SETMAR functions, more research and new tools are needed to better understand the cellular activities of SETMAR and to investigate the therapeutic potential of SETMAR.
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Affiliation(s)
- Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
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Nicolau M, Picault N, Moissiard G. The Evolutionary Volte-Face of Transposable Elements: From Harmful Jumping Genes to Major Drivers of Genetic Innovation. Cells 2021; 10:cells10112952. [PMID: 34831175 PMCID: PMC8616336 DOI: 10.3390/cells10112952] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/20/2021] [Accepted: 10/20/2021] [Indexed: 12/25/2022] Open
Abstract
Transposable elements (TEs) are self-replicating DNA elements that constitute major fractions of eukaryote genomes. Their ability to transpose can modify the genome structure with potentially deleterious effects. To repress TE activity, host cells have developed numerous strategies, including epigenetic pathways, such as DNA methylation or histone modifications. Although TE neo-insertions are mostly deleterious or neutral, they can become advantageous for the host under specific circumstances. The phenomenon leading to the appropriation of TE-derived sequences by the host is known as TE exaptation or co-option. TE exaptation can be of different natures, through the production of coding or non-coding DNA sequences with ultimately an adaptive benefit for the host. In this review, we first give new insights into the silencing pathways controlling TE activity. We then discuss a model to explain how, under specific environmental conditions, TEs are unleashed, leading to a TE burst and neo-insertions, with potential benefits for the host. Finally, we review our current knowledge of coding and non-coding TE exaptation by providing several examples in various organisms and describing a method to identify TE co-option events.
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Affiliation(s)
- Melody Nicolau
- LGDP-UMR5096, CNRS, 66860 Perpignan, France; (M.N.); (N.P.)
- LGDP-UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Nathalie Picault
- LGDP-UMR5096, CNRS, 66860 Perpignan, France; (M.N.); (N.P.)
- LGDP-UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
| | - Guillaume Moissiard
- LGDP-UMR5096, CNRS, 66860 Perpignan, France; (M.N.); (N.P.)
- LGDP-UMR5096, Université de Perpignan Via Domitia, 66860 Perpignan, France
- Correspondence:
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Zhang Y, Zhang N, Liu L, Wang Y, Xing J, Li X. Transcriptome Analysis of Effects of Folic Acid Supplement on Gene Expression in Liver of Broiler Chickens. Front Vet Sci 2021; 8:686609. [PMID: 34604366 PMCID: PMC8481781 DOI: 10.3389/fvets.2021.686609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 08/23/2021] [Indexed: 12/30/2022] Open
Abstract
Folic acid is a water-soluble B vitamin, and plays an important role in regulating gene expression and methylation. The liver is the major site of lipid biosynthesis in the chicken. Nevertheless, how gene expression and regulatory networks are affected by folic acid in liver of broilers are poorly understood. This paper conducted the RNA-seq technology on the liver of broilers under folic acid challenge investigation. First, 405 differentially expressed genes (DEGs), including 157 significantly upregulated and 248 downregulated, were detected between the control group (C) and the 5 mg folic acid group (M). Second, 68 upregulated DEGs and 142 downregulated DEGs were determined between C group and 10 mg folic acid group (H). Third, there were 165 upregulated genes and 179 downregulated genes between M and H groups. Of these DEGs, 903 DEGs were successfully annotated in the public databases. The functional classification based on GO and KEEGG showed that “general function prediction only” represented the largest functional classes, “cell cycle” (C vs. M; M vs. H), and “neuroactive ligand-receptor interaction” (C vs. H) were the highest unique sequences among three groups. SNP analysis indicated that numbers of C, M and H groups were 145,450, 146,131, and 123,004, respectively. Total new predicted alternative splicing events in C, M, and H groups were 9,521, 9,328, and 8,929, respectively. A protein-protein interaction (PPI) network was constructed, and the top 10 hub genes were evaluated among three groups. The results of real time PCR indicated that mRNA abundance of PPARγ and FAS in abdominal fat of M and H groups were reduced compared with the C group (P < 0.05). Ultramicroscopy results showed that folic acid could reduce lipid droplets in livers from chickens. Finally, contents of LPL, PPARγ, and FAS in abdominal fat were decreased with the folic acid supplmented diets (P < 0.01). These findings reveal the effects of folic acid supplemention on gene expression in liver of broilers, which can provide information for understanding the molecular mechanisms of folic acid regulating liver lipid metabolism.
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Affiliation(s)
- Yujie Zhang
- School of Life Sciences, Linyi University, Linyi, China
| | - Ningbo Zhang
- School of Agriculture and Forestry Sciences, Linyi University, Linyi, China
| | - Lin Liu
- School of Pharmacy, Linyi University, Linyi, China
| | - Yan Wang
- School of Life Sciences, Linyi University, Linyi, China
| | - Jinyi Xing
- School of Life Sciences, Linyi University, Linyi, China
| | - Xiuling Li
- School of Life Sciences, Linyi University, Linyi, China
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Miskei M, Horváth A, Viola L, Varga L, Nagy É, Feró O, Karányi Z, Roszik J, Miskey C, Ivics Z, Székvölgyi L. Genome-wide mapping of binding sites of the transposase-derived SETMAR protein in the human genome. Comput Struct Biotechnol J 2021; 19:4032-4041. [PMID: 34377368 PMCID: PMC8327481 DOI: 10.1016/j.csbj.2021.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/12/2021] [Accepted: 07/12/2021] [Indexed: 01/04/2023] Open
Abstract
Throughout evolution, DNA transposons provide a recurrent supply of genetic information to give rise to novel gene functions by fusion of their transposase domain to various domains of host-encoded proteins. One of these "domesticated", transposase-derived factors is SETMAR/Metnase which is a naturally occurring fusion protein that consists of a histone-lysine methyltransferase domain and an HsMar1 transposase. To elucidate the biological role of SETMAR, it is crucial to identify genomic targets to which SETMAR specifically binds and link these sites to the regulation of gene expression. Herein, we mapped the genomic landscape of SETMAR binding in a near-haploid human leukemia cell line (HAP1) in order to identify on-target and off-target binding sites at high resolution and to elucidate their role in terms of gene expression. Our analysis revealed a perfect correlation between SETMAR and inverted terminal repeats (ITRs) of HsMar1 transposon remnants, which are considered as natural target sites for SETMAR binding. However, we did not detect any untargeted events at non-ITR sequences, calling into question previously proposed off-target binding sites. We identified sequence fidelity of the ITR motif as a key factor for determining the binding affinity of SETMAR for chromosomes, as higher conservation of ITR sequences resulted in increased affinity for chromatin and stronger repression of SETMAR-bound gene loci. These associations highlight how SETMAR's chromatin binding fine-tune gene regulatory networks in human tumour cells.
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Affiliation(s)
- Márton Miskei
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Adrienn Horváth
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Lívia Viola
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Laura Varga
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Éva Nagy
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Orsolya Feró
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Zsolt Karányi
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
- Department of Internal Medicine, Faculty of Medicine, University of Debrecen, Hungary
| | - Jason Roszik
- Department of Melanoma Medical Oncology, Division of Cancer Medicine, MD Anderson Cancer Centre, University of Texas, USA
| | - Csaba Miskey
- Division of Medical Biotechnology, Paul Ehrlich Institute, Langen D-63225, Germany
| | - Zoltán Ivics
- Division of Medical Biotechnology, Paul Ehrlich Institute, Langen D-63225, Germany
| | - Lóránt Székvölgyi
- MTA-DE Momentum Genome Architecture and Recombination Research Group, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
- Faculty of Pharmacy, University of Debrecen, Hungary
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Antoine-Lorquin A, Arensburger P, Arnaoty A, Asgari S, Batailler M, Beauclair L, Belleannée C, Buisine N, Coustham V, Guyetant S, Helou L, Lecomte T, Pitard B, Stévant I, Bigot Y. Two repeated motifs enriched within some enhancers and origins of replication are bound by SETMAR isoforms in human colon cells. Genomics 2021; 113:1589-1604. [PMID: 33812898 DOI: 10.1016/j.ygeno.2021.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 11/15/2022]
Abstract
Setmar is a gene specific to simian genomes. The function(s) of its isoforms are poorly understood and their existence in healthy tissues remains to be validated. Here we profiled SETMAR expression and its genome-wide binding landscape in colon tissue. We found isoforms V3 and V6 in healthy and tumour colon tissues as well as incell lines. In two colorectal cell lines SETMAR binds to several thousand Hsmar1 and MADE1 terminal ends, transposons mostly located in non-genic regions of active chromatin including in enhancers. It also binds to a 12-bp motifs similar to an inner motif in Hsmar1 and MADE1 terminal ends. This motif is interspersed throughout the genome and is enriched in GC-rich regions as well as in CpG islands that contain constitutive replication origins. It is also found in enhancers other than those associated with Hsmar1 and MADE1. The role of SETMAR in the expression of genes, DNA replication and in DNA repair are discussed.
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Affiliation(s)
| | - Peter Arensburger
- Biological Sciences Department, California State Polytechnic University, Pomona, CA 91768, - United States
| | - Ahmed Arnaoty
- EA GICC, 7501, CHRU de Tours, 37044 TOURS, Cedex 09, France
| | - Sassan Asgari
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Martine Batailler
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | - Linda Beauclair
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | | | - Nicolas Buisine
- UMR CNRS 7221, Muséum National d'Histoire Naturelle, 75005 Paris, France
| | | | - Serge Guyetant
- Tumorothèque du CHRU de Tours, 37044 Tours, Cedex, France
| | - Laura Helou
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France
| | | | - Bruno Pitard
- Université de Nantes, CNRS ERL6001, Inserm 1232, CRCINA, F-44000 Nantes, France
| | - Isabelle Stévant
- Institut de Génomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon, 1, 46 allée d'Italie, 69364 Lyon, France
| | - Yves Bigot
- PRC, UMR INRA 0085, CNRS 7247, Centre INRA Val de Loire, 37380 Nouzilly, France.
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14
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Di Nisio E, Lupo G, Licursi V, Negri R. The Role of Histone Lysine Methylation in the Response of Mammalian Cells to Ionizing Radiation. Front Genet 2021; 12:639602. [PMID: 33859667 PMCID: PMC8042281 DOI: 10.3389/fgene.2021.639602] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/11/2021] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic genomes are wrapped around nucleosomes and organized into different levels of chromatin structure. Chromatin organization has a crucial role in regulating all cellular processes involving DNA-protein interactions, such as DNA transcription, replication, recombination and repair. Histone post-translational modifications (HPTMs) have a prominent role in chromatin regulation, acting as a sophisticated molecular code, which is interpreted by HPTM-specific effectors. Here, we review the role of histone lysine methylation changes in regulating the response to radiation-induced genotoxic damage in mammalian cells. We also discuss the role of histone methyltransferases (HMTs) and histone demethylases (HDMs) and the effects of the modulation of their expression and/or the pharmacological inhibition of their activity on the radio-sensitivity of different cell lines. Finally, we provide a bioinformatic analysis of published datasets showing how the mRNA levels of known HMTs and HDMs are modulated in different cell lines by exposure to different irradiation conditions.
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Affiliation(s)
- Elena Di Nisio
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, Rome, Italy
| | - Giuseppe Lupo
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, Rome, Italy
| | - Valerio Licursi
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, Rome, Italy
| | - Rodolfo Negri
- Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, Rome, Italy.,Institute of Molecular Biology and Pathology, National Research Counsil (IBPM-CNR), Rome, Italy
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15
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Cosby RL, Judd J, Zhang R, Zhong A, Garry N, Pritham EJ, Feschotte C. Recurrent evolution of vertebrate transcription factors by transposase capture. Science 2021; 371:eabc6405. [PMID: 33602827 PMCID: PMC8186458 DOI: 10.1126/science.abc6405] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 12/18/2020] [Indexed: 12/13/2022]
Abstract
Genes with novel cellular functions may evolve through exon shuffling, which can assemble novel protein architectures. Here, we show that DNA transposons provide a recurrent supply of materials to assemble protein-coding genes through exon shuffling. We find that transposase domains have been captured-primarily via alternative splicing-to form fusion proteins at least 94 times independently over the course of ~350 million years of tetrapod evolution. We find an excess of transposase DNA binding domains fused to host regulatory domains, especially the Krüppel-associated box (KRAB) domain, and identify four independently evolved KRAB-transposase fusion proteins repressing gene expression in a sequence-specific fashion. The bat-specific KRABINER fusion protein binds its cognate transposons genome-wide and controls a network of genes and cis-regulatory elements. These results illustrate how a transcription factor and its binding sites can emerge.
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Affiliation(s)
- Rachel L Cosby
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Julius Judd
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Ruiling Zhang
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Alan Zhong
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Nathaniel Garry
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
| | - Ellen J Pritham
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Cédric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA.
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16
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Xie R, Chen X, Cheng L, Huang M, Zhou Q, Zhang J, Chen Y, Peng S, Chen Z, Dong W, Huang J, Lin T. NONO Inhibits Lymphatic Metastasis of Bladder Cancer via Alternative Splicing of SETMAR. Mol Ther 2020; 29:291-307. [PMID: 32950106 DOI: 10.1016/j.ymthe.2020.08.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 07/13/2020] [Accepted: 08/21/2020] [Indexed: 12/25/2022] Open
Abstract
Bladder cancer patients with lymph node (LN) metastasis have an extremely poor prognosis and no effective treatment. The alternative splicing of precursor (pre-)mRNA participates in the progression of various tumors. However, the precise mechanisms of splicing factors and cancer-related variants in LN metastasis of bladder cancer remain largely unknown. The present study identified a splicing factor, non-POU domain-containing octamer-binding protein (NONO), that was significantly downregulated in bladder cancer tissues and correlated with LN metastasis status, tumor stage, and prognosis. Functionally, NONO markedly inhibited bladder cancer cell migration and invasion in vitro and LN metastasis in vivo. Mechanistically, NONO regulated the exon skipping of SETMAR by binding to its motif, mainly through the RRM2 domain. NONO directly interacted with splicing factor proline/glutamine rich (SFPQ) to regulate the splicing of SETMAR, and it induced metastasis suppression of bladder cancer cells. SETMAR-L overexpression significantly reversed the metastasis of NONO-knockdown bladder cancer cells, both in vitro and in vivo. The further analysis revealed that NONO-mediated SETMAR-L can induce H3K27me3 at the promotor of metastatic oncogenes and inhibit their transcription, ultimately resulting in metastasis suppression. Therefore, the present findings uncover the molecular mechanism of lymphatic metastasis in bladder cancer, which may provide novel clinical markers and therapeutic strategies for LN-metastatic bladder cancer.
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Affiliation(s)
- Ruihui Xie
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Xu Chen
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
| | - Liang Cheng
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Ming Huang
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Qianghua Zhou
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Jingtong Zhang
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yuelong Chen
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Shengmeng Peng
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Ziyue Chen
- Department of Pediatric Surgery, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Wen Dong
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jian Huang
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
| | - Tianxin Lin
- Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China; Department of Urology, The Affiliated Kashi Hospital, Sun Yat-sen University, Kashi, China.
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17
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Dupeyron M, Baril T, Bass C, Hayward A. Phylogenetic analysis of the Tc1/mariner superfamily reveals the unexplored diversity of pogo-like elements. Mob DNA 2020; 11:21. [PMID: 32612713 PMCID: PMC7325037 DOI: 10.1186/s13100-020-00212-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 04/08/2020] [Indexed: 01/18/2023] Open
Abstract
Background Tc1/mariner transposons are widespread DNA transposable elements (TEs) that have made important contributions to the evolution of host genomic complexity in metazoans. However, the evolution and diversity of the Tc1/mariner superfamily remains poorly understood. Following recent developments in genome sequencing and the availability of a wealth of new genomes, Tc1/mariner TEs have been identified in many new taxa across the eukaryotic tree of life. To date, the majority of studies focussing on Tc1/mariner elements have considered only a single host lineage or just a small number of host lineages. Thus, much remains to be learnt about the evolution of Tc1/mariner TEs by performing analyses that consider elements that originate from across host diversity. Results We mined the non-redundant database of NCBI using BLASTp searches, with transposase sequences from a diverse set of reference Tc1/mariner elements as queries. A total of 5158 Tc1/mariner elements were retrieved and used to reconstruct evolutionary relationships within the superfamily. The resulting phylogeny is well resolved and includes several new groups of Tc1/mariner elements. In particular, we identify a new family of plant-genome restricted Tc1/mariner elements, which we call PlantMar. We also show that the pogo family is much larger and more diverse than previously appreciated, and we review evidence for a potential revision of its status to become a separate superfamily. Conclusions Our study provides an overview of Tc1-mariner phylogeny and summarises the impressive diversity of Tc1-mariner TEs among sequenced eukaryotes. Tc1/mariner TEs are successful in a wide range of eukaryotes, especially unikonts (the taxonomic supergroup containing Amoebozoa, Opisthokonta, Breviatea, and Apusomonadida). In particular, ecdysozoa, and especially arthropods, emerge as important hosts for Tc1/mariner elements (except the PlantMar family). Meanwhile, the pogo family, which is by far the largest Tc1/mariner family, also includes many elements from fungal and chordate genomes. Moreover, there is evidence of the repeated exaptation of pogo elements in vertebrates, including humans, in addition to the well-known example of CENP-B. Collectively, our findings provide a considerable advancement in understanding of Tc1/mariner elements, and more generally they suggest that much work remains to improve understanding of the diversity and evolution of DNA TEs.
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Affiliation(s)
- Mathilde Dupeyron
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE UK
| | - Tobias Baril
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE UK
| | - Chris Bass
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE UK
| | - Alexander Hayward
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE UK
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18
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Abstract
Since Barbara McClintock’s groundbreaking discovery of mobile DNA sequences some 70 years ago, transposable elements have come to be recognized as important mutagenic agents impacting genome composition, genome evolution, and human health. Transposable elements are a major constituent of prokaryotic and eukaryotic genomes, and the transposition mechanisms enabling transposon proliferation over evolutionary time remain engaging topics for study, suggesting complex interactions with the host, both antagonistic and mutualistic. The impact of transposition is profound, as over 100 human heritable diseases have been attributed to transposon insertions. Transposition can be highly mutagenic, perturbing genome integrity and gene expression in a wide range of organisms. This mutagenic potential has been exploited in the laboratory, where transposons have long been utilized for phenotypic screening and the generation of defined mutant libraries. More recently, barcoding applications and methods for RNA-directed transposition are being used towards new phenotypic screens and studies relevant for gene therapy. Thus, transposable elements are significant in affecting biology both
in vivo and in the laboratory, and this review will survey advances in understanding the biological role of transposons and relevant laboratory applications of these powerful molecular tools.
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Affiliation(s)
- Anuj Kumar
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.,Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA
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19
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Tellier M, Chalmers R. Compensating for over-production inhibition of the Hsmar1 transposon in Escherichia coli using a series of constitutive promoters. Mob DNA 2020; 11:5. [PMID: 31938044 PMCID: PMC6954556 DOI: 10.1186/s13100-020-0200-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 01/01/2020] [Indexed: 01/03/2023] Open
Abstract
Background Transposable elements (TEs) are a diverse group of self-mobilizing DNA elements. Transposition has been exploited as a powerful tool for molecular biology and genomics. However, transposition is sometimes limited because of auto-regulatory mechanisms that presumably allow them to cohabit within their hosts without causing excessive genomic damage. The papillation assay provides a powerful visual screen for hyperactive transposases. Transposition is revealed by the activation of a promoter-less lacZ gene when the transposon integrates into a non-essential gene on the host chromosome. Transposition events are detected as small blue speckles, or papillae, on the white background of the main Escherichia coli colony. Results We analysed the parameters of the papillation assay including the strength of the transposase transcriptional and translational signals. To overcome certain limitations of inducible promoters, we constructed a set of vectors based on constitutive promoters of different strengths to widen the range of transposase expression. We characterized and validated our expression vectors with Hsmar1, a member of the mariner transposon family. The highest rate of transposition was observed with the weakest promoters. We then took advantage of our approach to investigate how the level of transposition responds to selected point mutations and the effect of joining the transposase monomers into a single-chain dimer. Conclusions We generated a set of vectors to provide a wide range of transposase expression which will be useful for screening libraries of transposase mutants. The use of weak promoters should allow screening for truly hyperactive transposases rather than those that are simply resistant to auto-regulatory mechanisms, such as overproduction inhibition (OPI). We also found that mutations in the Hsmar1 dimer interface provide resistance to OPI in bacteria, which could be valuable for improving bacterial transposon mutagenesis techniques.
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Affiliation(s)
- Michael Tellier
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH UK.,2Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
| | - Ronald Chalmers
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH UK
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20
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Martinez-Gomez L, Abascal F, Jungreis I, Pozo F, Kellis M, Mudge JM, Tress ML. Few SINEs of life: Alu elements have little evidence for biological relevance despite elevated translation. NAR Genom Bioinform 2019; 2:lqz023. [PMID: 31886458 PMCID: PMC6924539 DOI: 10.1093/nargab/lqz023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 10/30/2019] [Accepted: 12/12/2019] [Indexed: 12/12/2022] Open
Abstract
Transposable elements colonize genomes and with time may end up being incorporated into functional regions. SINE Alu elements, which appeared in the primate lineage, are ubiquitous in the human genome and more than a thousand overlap annotated coding exons. Although almost all Alu-derived coding exons appear to be in alternative transcripts, they have been incorporated into the main coding transcript in at least 11 genes. The extent to which Alu regions are incorporated into functional proteins is unclear, but we detected reliable peptide evidence to support the translation to protein of 33 Alu-derived exons. All but one of the Alu elements for which we detected peptides were frame-preserving and there was proportionally seven times more peptide evidence for Alu elements as for other primate exons. Despite this strong evidence for translation to protein we found no evidence of selection, either from cross species alignments or human population variation data, among these Alu-derived exons. Overall, our results confirm that SINE Alu elements have contributed to the expansion of the human proteome, and this contribution appears to be stronger than might be expected over such a relatively short evolutionary timeframe. Despite this, the biological relevance of these modifications remains open to question.
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Affiliation(s)
- Laura Martinez-Gomez
- Bioinformatics Unit, Spanish National Cancer Research Centre, 28029 Madrid, Spain
| | | | - Irwin Jungreis
- MIT Computer Science and Artificial Intelligence Laboratory, Cambridge, MA and Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
| | - Fernando Pozo
- Bioinformatics Unit, Spanish National Cancer Research Centre, 28029 Madrid, Spain
| | - Manolis Kellis
- MIT Computer Science and Artificial Intelligence Laboratory, Cambridge, MA and Broad Institute of MIT and Harvard, Cambridge, MA 02139, USA
| | - Jonathan M Mudge
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Michael L Tress
- Bioinformatics Unit, Spanish National Cancer Research Centre, 28029 Madrid, Spain
- To whom correspondence should be addressed. Tel: +34 91 732 8000; Fax: +34 91 224 6980;
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21
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Tellier M, Chalmers R. The roles of the human SETMAR (Metnase) protein in illegitimate DNA recombination and non-homologous end joining repair. DNA Repair (Amst) 2019; 80:26-35. [PMID: 31238295 PMCID: PMC6715855 DOI: 10.1016/j.dnarep.2019.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 02/07/2023]
Abstract
Full length SETMAR expression has no effect on DNA repair and integration in vivo. SETMAR putative nuclease activity is not required in vivo. Separate expression of the SET and MAR domains affects DNA repair and integration. SETMAR isoform with a truncated SET-domain is specific to species containing the MAR domain.
SETMAR is a fusion between a SET-domain methyltransferase gene and a mariner-family transposase gene, which is specific to anthropoid primates. However, the ancestral SET gene is present in all other mammals and birds. SETMAR is reported to be involved in transcriptional regulation and a diverse set of reactions related to DNA repair. Since the transcriptional effects of SETMAR depend on site-specific DNA binding, and are perturbed by inactivating the methyltransferase, we wondered whether we could differentiate the effects of the SET and MAR domains in DNA repair assays. We therefore generated several stable U2OS cell lines expressing either wild type SETMAR or truncation or point mutant variants. We tested these cell lines with in vivo plasmid-based assays to determine the relevance of the different domains and activities of SETMAR in DNA repair. Contrary to previous reports, we found that wild type SETMAR had little to no effect on the rate of cell division, DNA integration into the genome or non-homologous end joining. Also contrary to previous reports, we failed to detect any effect of a strong active-site mutation that should have knocked out the putative nuclease activity of SETMAR.
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Affiliation(s)
- Michael Tellier
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
| | - Ronald Chalmers
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
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