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Khan M, Shah S, Lv B, Lv Z, Ji N, Song Z, Wu P, Wang X, Mehmood A. Molecular Mechanisms of Alu and LINE-1 Interspersed Repetitive Sequences Reveal Diseases of Visual System Dysfunction. Ocul Immunol Inflamm 2023; 31:1848-1858. [PMID: 36040959 DOI: 10.1080/09273948.2022.2112238] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 08/05/2022] [Indexed: 10/14/2022]
Abstract
BACKGROUND Short interspersed nuclear elements (SINEs) and long interspersed nuclear elements (LINE-1s) are the abundant and well-characterized repetitive elements in the human genome. METHODS For this review, all relevant original research studies were assessed by searching electronic databases, including PubMed, Google Scholar, and Web of Science, by using relevant keywords. Accumulating evidence indicates that the disorder of gene expression regulated by these repetitive sequences is one of the causes of the diseases of visual system dysfunction, including retinal degenerations, glaucoma, retinitis punctata albescens, retinitis pigmentosa, geographic atrophy, and age-related macular degeneration, suggesting that SINEs and LINE-1s may have great potential implications in ophthalmology. RESULTS Alu elements belonging to the SINEs are present in more than one million copies, comprising 10% of the human genome. CONCLUSION This study offers recent advances in Alu and LINE-1 mechanisms in the development of eye diseases. The current study could advance our knowledge of the roles of SINEs and LINE-1s in the developing process of eye diseases, suggesting new diagnostic biomarkers, therapeutic strategies, and significant points for future studies.
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Affiliation(s)
- Murad Khan
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Suleman Shah
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Baixue Lv
- Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
- Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, China
| | - Zhanjun Lv
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Ning Ji
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Zhixue Song
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Peiyuan Wu
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Xiufang Wang
- Department of Genetics, Hebei Medical University, Hebei Key Lab of Laboratory Animal, Shijiazhuang, Hebei Province, China
| | - Arshad Mehmood
- Department of Neurology, the Second Hospital of Hebei Medical University, City Shijiazhuang, P.R. China
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2
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Dynamic Variations of 3'UTR Length Reprogram the mRNA Regulatory Landscape. Biomedicines 2021; 9:biomedicines9111560. [PMID: 34829789 PMCID: PMC8615635 DOI: 10.3390/biomedicines9111560] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/10/2021] [Accepted: 10/15/2021] [Indexed: 12/16/2022] Open
Abstract
This paper concerns 3′-untranslated regions (3′UTRs) of mRNAs, which are non-coding regulatory platforms that control stability, fate and the correct spatiotemporal translation of mRNAs. Many mRNAs have polymorphic 3′UTR regions. Controlling 3′UTR length and sequence facilitates the regulation of the accessibility of functional effectors (RNA binding proteins, miRNAs or other ncRNAs) to 3′UTR functional boxes and motifs and the establishment of different regulatory landscapes for mRNA function. In this context, shortening of 3′UTRs would loosen miRNA or protein-based mechanisms of mRNA degradation, while 3′UTR lengthening would strengthen accessibility to these effectors. Alterations in the mechanisms regulating 3′UTR length would result in widespread deregulation of gene expression that could eventually lead to diseases likely linked to the loss (or acquisition) of specific miRNA binding sites. Here, we will review the mechanisms that control 3′UTR length dynamics and their alterations in human disorders. We will discuss, from a mechanistic point of view centered on the molecular machineries involved, the generation of 3′UTR variability by the use of alternative polyadenylation and cleavage sites, of mutually exclusive terminal alternative exons (exon skipping) as well as by the process of exonization of Alu cassettes to generate new 3′UTRs with differential functional features.
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3
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Li M, Larsen PA. Primate-specific retrotransposons and the evolution of circadian networks in the human brain. Neurosci Biobehav Rev 2021; 131:988-1004. [PMID: 34592258 DOI: 10.1016/j.neubiorev.2021.09.049] [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: 04/05/2021] [Revised: 08/03/2021] [Accepted: 09/26/2021] [Indexed: 11/26/2022]
Abstract
The circadian rhythm of the human brain is attuned to sleep-wake cycles that entail global alterations in neuronal excitability. This periodicity involves a highly coordinated regulation of gene expression. A growing number of studies are documenting a fascinating connection between primate-specific retrotransposons (Alu elements) and key epigenetic regulatory processes in the primate brain. Collectively, these studies indicate that Alu elements embedded in the human neuronal genome mediate post-transcriptional processes that unite human-specific neuroepigenetic landscapes and circadian rhythm. Here, we review evidence linking Alu retrotransposon-mediated posttranscriptional pathways to circadian gene expression. We hypothesize that Alu retrotransposons participate in the organization of circadian brain function through multidimensional neuroepigenetic pathways. We anticipate that these pathways are closely tied to the evolution of human cognition and their perturbation contributes to the manifestation of human-specific neurological diseases. Finally, we address current challenges and accompanying opportunities in studying primate- and human-specific transposable elements.
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Affiliation(s)
- Manci Li
- University of Minnesota, St. Paul, MN, 55108, United States
| | - Peter A Larsen
- University of Minnesota, St. Paul, MN, 55108, United States.
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4
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Maurya R, Kanakan A, Vasudevan JS, Chattopadhyay P, Pandey R. Infection outcome needs two to tango: human host and the pathogen. Brief Funct Genomics 2021; 21:90-102. [PMID: 34402498 PMCID: PMC8385967 DOI: 10.1093/bfgp/elab037] [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: 06/15/2021] [Revised: 07/15/2021] [Accepted: 07/21/2021] [Indexed: 12/15/2022] Open
Abstract
Infectious diseases are potential drivers for human evolution, through a complex, continuous and dynamic interaction between the host and the pathogen/s. It is this dynamic interaction that contributes toward the clinical outcome of a pathogenic disease. These are modulated by contributions from the human genetic variants, transcriptional response (including noncoding RNA) and the pathogen’s genome architecture. Modern genomic tools and techniques have been crucial for the detection and genomic characterization of pathogens with respect to the emerging infectious diseases. Aided by next-generation sequencing (NGS), risk stratification of host population/s allows for the identification of susceptible subgroups and better disease management. Nevertheless, many challenges to a general understanding of host–pathogen interactions remain. In this review, we elucidate how a better understanding of the human host-pathogen interplay can substantially enhance, and in turn benefit from, current and future applications of multi-omics based approaches in infectious and rare diseases. This includes the RNA-level response, which modulates the disease severity and outcome. The need to understand the role of human genetic variants in disease severity and clinical outcome has been further highlighted during the Coronavirus disease 2019 (COVID-19) pandemic. This would enhance and contribute toward our future pandemic preparedness.
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Affiliation(s)
- Ranjeet Maurya
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Akshay Kanakan
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India
| | - Janani Srinivasa Vasudevan
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India
| | - Partha Chattopadhyay
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Rajesh Pandey
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
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5
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Simna SP, Han Z. Prospects Of Non-Coding Elements In Genomic Dna Based Gene Therapy. Curr Gene Ther 2021; 22:89-103. [PMID: 33874871 DOI: 10.2174/1566523221666210419090357] [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: 12/05/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/22/2022]
Abstract
Gene therapy has made significant development since the commencement of the first clinical trials a few decades ago and has remained a dynamic area of research regardless of obstacles such as immune response and insertional mutagenesis. Progression in various technologies like next-generation sequencing (NGS) and nanotechnology has established the importance of non-coding segments of a genome, thereby taking gene therapy to the next level. In this review, we have summarized the importance of non-coding elements, highlighting the advantages of using full-length genomic DNA loci (gDNA) compared to complementary DNA (cDNA) or minigene, currently used in gene therapy. The focus of this review is to provide an overview of the advances and the future of potential use of gDNA loci in gene therapy, expanding the therapeutic repertoire in molecular medicine.
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Affiliation(s)
- S P Simna
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
| | - Zongchao Han
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
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6
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Li M, Schifanella L, Larsen PA. Alu retrotransposons and COVID-19 susceptibility and morbidity. Hum Genomics 2021; 15:2. [PMID: 33390179 PMCID: PMC7779329 DOI: 10.1186/s40246-020-00299-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/14/2020] [Indexed: 12/22/2022] Open
Abstract
SARS-CoV-2 has spread rapidly across the world and is negatively impacting the global human population. COVID-19 patients display a wide variety of symptoms and clinical outcomes, including those attributed to genetic ancestry. Alu retrotransposons have played an important role in human evolution, and their variants influence host response to viral infection. Intronic Alus regulate gene expression through several mechanisms, including both genetic and epigenetic pathways. With respect to SARS-CoV-2, an intronic Alu within the ACE gene is hypothesized to be associated with COVID-19 susceptibility and morbidity. Here, we review specific Alu polymorphisms that are of particular interest when considering host response to SARS-CoV-2 infection, especially polymorphic Alu insertions in genes associated with immune response and coagulation/fibrinolysis cascade. We posit that additional research focused on Alu-related pathways could yield novel biomarkers capable of predicting clinical outcomes as well as patient-specific treatment strategies for COVID-19 and related infectious diseases.
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Affiliation(s)
- Manci Li
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, 55108, USA
| | - Luca Schifanella
- Department of Surgery, Division of Surgical Outcomes and Precision Medicine Research, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | - Peter A Larsen
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, 55108, USA.
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7
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Navarro E, Mallén A, Cruzado JM, Torras J, Hueso M. Unveiling ncRNA regulatory axes in atherosclerosis progression. Clin Transl Med 2020; 9:5. [PMID: 32009226 PMCID: PMC6995802 DOI: 10.1186/s40169-020-0256-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 01/05/2020] [Indexed: 02/06/2023] Open
Abstract
Completion of the human genome sequencing project highlighted the richness of the cellular RNA world, and opened the door to the discovery of a plethora of short and long non-coding RNAs (the dark transcriptome) with regulatory or structural potential, which shifted the balance of pathological gene alterations from coding to non-coding RNAs. Thus, disease risk assessment currently has to also evaluate the expression of new RNAs such as small micro RNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), competing endogenous RNAs (ceRNAs), retrogressed elements, 3'UTRs of mRNAs, etc. We are interested in the pathogenic mechanisms of atherosclerosis (ATH) progression in patients suffering Chronic Kidney Disease, and in this review, we will focus in the role of the dark transcriptome (non-coding RNAs) in ATH progression. We will focus in miRNAs and in the formation of regulatory axes or networks with their mRNA targets and with the lncRNAs that function as miRNA sponges or competitive inhibitors of miRNA activity. In this sense, we will pay special attention to retrogressed genomic elements, such as processed pseudogenes and Alu repeated elements, that have been recently seen to also function as miRNA sponges, as well as to the use or miRNA derivatives in gene silencing, anti-ATH therapies. Along the review, we will discuss technical developments associated to research in lncRNAs, from sequencing technologies to databases, repositories and algorithms to predict miRNA targets, as well as new approaches to miRNA function, such as integrative or enrichment analysis and their potential to unveil RNA regulatory networks.
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Affiliation(s)
- Estanislao Navarro
- Independent Researcher, Barcelona, Spain. .,Department of Nephrology, Hospital Universitari Bellvitge and Bellvitge Research Institute (IDIBELL), C/Feixa Llarga, s/n; L'Hospitalet de Llobregat, 08907, Barcelona, Spain.
| | - Adrian Mallén
- Department of Nephrology, Hospital Universitari Bellvitge and Bellvitge Research Institute (IDIBELL), C/Feixa Llarga, s/n; L'Hospitalet de Llobregat, 08907, Barcelona, Spain
| | - Josep M Cruzado
- Department of Nephrology, Hospital Universitari Bellvitge and Bellvitge Research Institute (IDIBELL), C/Feixa Llarga, s/n; L'Hospitalet de Llobregat, 08907, Barcelona, Spain
| | - Joan Torras
- Department of Nephrology, Hospital Universitari Bellvitge and Bellvitge Research Institute (IDIBELL), C/Feixa Llarga, s/n; L'Hospitalet de Llobregat, 08907, Barcelona, Spain
| | - Miguel Hueso
- Department of Nephrology, Hospital Universitari Bellvitge and Bellvitge Research Institute (IDIBELL), C/Feixa Llarga, s/n; L'Hospitalet de Llobregat, 08907, Barcelona, Spain.
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8
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Roychowdhury T, Abyzov A. Chromatin organization modulates the origin of heritable structural variations in human genome. Nucleic Acids Res 2019; 47:2766-2777. [PMID: 30773596 PMCID: PMC6451188 DOI: 10.1093/nar/gkz103] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/06/2019] [Accepted: 02/14/2019] [Indexed: 12/11/2022] Open
Abstract
Structural variations (SVs) in the human genome originate from different mechanisms related to DNA repair, replication errors, and retrotransposition. Our analyses of 26 927 SVs from the 1000 Genomes Project revealed differential distributions and consequences of SVs of different origin, e.g. deletions from non-allelic homologous recombination (NAHR) are more prone to disrupt chromatin organization while processed pseudogenes can create accessible chromatin. Spontaneous double stranded breaks (DSBs) are the best predictor of enrichment of NAHR deletions in open chromatin. This evidence, along with strong physical interaction of NAHR breakpoints belonging to the same deletion suggests that majority of NAHR deletions are non-meiotic i.e. originate from errors during homology directed repair (HDR) of spontaneous DSBs. In turn, the origin of the spontaneous DSBs is associated with transcription factor binding in accessible chromatin revealing the vulnerability of functional, open chromatin. The chromatin itself is enriched with repeats, particularly fixed Alu elements that provide the homology required to maintain stability via HDR. Through co-localization of fixed Alus and NAHR deletions in open chromatin we hypothesize that old Alu expansion had a stabilizing role on the human genome.
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Affiliation(s)
- Tanmoy Roychowdhury
- Mayo Clinic, Department of Health Sciences Research, Center for Individualized Medicine, Rochester, MN 55905, USA
| | - Alexej Abyzov
- Mayo Clinic, Department of Health Sciences Research, Center for Individualized Medicine, Rochester, MN 55905, USA
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9
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Guffanti G, Bartlett A, Klengel T, Klengel C, Hunter R, Glinsky G, Macciardi F. Novel Bioinformatics Approach Identifies Transcriptional Profiles of Lineage-Specific Transposable Elements at Distinct Loci in the Human Dorsolateral Prefrontal Cortex. Mol Biol Evol 2019; 35:2435-2453. [PMID: 30053206 PMCID: PMC6188555 DOI: 10.1093/molbev/msy143] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Expression of transposable elements (TE) is transiently activated during human preimplantation embryogenesis in a developmental stage- and cell type-specific manner and TE-mediated epigenetic regulation is intrinsically wired in developmental genetic networks in human embryos and embryonic stem cells. However, there are no systematic studies devoted to a comprehensive analysis of the TE transcriptome in human adult organs and tissues, including human neural tissues. To investigate TE expression in the human Dorsolateral Prefrontal Cortex (DLPFC), we developed and validated a straightforward analytical approach to chart quantitative genome-wide expression profiles of all annotated TE loci based on unambiguous mapping of discrete TE-encoded transcripts using a de novo assembly strategy. To initially evaluate the potential regulatory impact of DLPFC-expressed TE, we adopted a comparative evolutionary genomics approach across humans, primates, and rodents to document conservation patterns, lineage-specificity, and colocalizations with transcription factor binding sites mapped within primate- and human-specific TE. We identified 654,665 transcripts expressed from 477,507 distinct loci of different TE classes and families, the majority of which appear to have originated from primate-specific sequences. We discovered 4,687 human-specific and transcriptionally active TEs in DLPFC, of which the prominent majority (80.2%) appears spliced. Our analyses revealed significant associations of DLPFC-expressed TE with primate- and human-specific transcription factor binding sites, suggesting potential cross-talks of concordant regulatory functions. We identified 1,689 TEs differentially expressed in the DLPFC of Schizophrenia patients, a majority of which is located within introns of 1,137 protein-coding genes. Our findings imply that identified DLPFC-expressed TEs may affect human brain structures and functions following different evolutionary trajectories. On one side, hundreds of thousands of TEs maintained a remarkably high conservation for ∼8 My of primates’ evolution, suggesting that they are likely conveying evolutionary-constrained primate-specific regulatory functions. In parallel, thousands of transcriptionally active human-specific TE loci emerged more recently, suggesting that they could be relevant for human-specific behavioral or cognitive functions.
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Affiliation(s)
- Guia Guffanti
- Department of Psychiatry, Harvard Medical School, Cambridge, MA.,Division of Depression and Anxiety, McLean Hospital, Belmont, MA
| | - Andrew Bartlett
- Department of Psychology, University of Massachusetts, Boston, MA
| | - Torsten Klengel
- Department of Psychiatry, Harvard Medical School, Cambridge, MA.,Division of Depression and Anxiety, McLean Hospital, Belmont, MA.,Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Goettingen, Germany
| | - Claudia Klengel
- Department of Psychiatry, Harvard Medical School, Cambridge, MA.,Division of Depression and Anxiety, McLean Hospital, Belmont, MA
| | - Richard Hunter
- Department of Psychology, University of Massachusetts, Boston, MA
| | - Gennadi Glinsky
- Translational & Functional Genomics, Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA
| | - Fabio Macciardi
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA
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10
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Guichard E, Peona V, Malagoli Tagliazucchi G, Abitante L, Jagoda E, Musella M, Ricci M, Rubio-Roldán A, Sarno S, Luiselli D, Pettener D, Taccioli C, Pagani L, Garcia-Perez JL, Boattini A. Impact of non-LTR retrotransposons in the differentiation and evolution of anatomically modern humans. Mob DNA 2018; 9:28. [PMID: 30147753 PMCID: PMC6094920 DOI: 10.1186/s13100-018-0133-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 08/07/2018] [Indexed: 12/31/2022] Open
Abstract
Background Transposable elements are biologically important components of eukaryote genomes. In particular, non-LTR retrotransposons (N-LTRrs) played a key role in shaping the human genome throughout evolution. In this study, we compared retrotransposon insertions differentially present in the genomes of Anatomically Modern Humans, Neanderthals, Denisovans and Chimpanzees, in order to assess the possible impact of retrotransposition in the differentiation of the human lineage. Results We first identified species-specific N-LTRrs and established their distribution in present day human populations. These analyses shortlisted a group of N-LTRr insertions that were found exclusively in Anatomically Modern Humans. These insertions are associated with an increase in the number of transcriptional/splicing variants of those genes they inserted in. The analysis of the functionality of genes containing human-specific N-LTRr insertions reflects changes that occurred during human evolution. In particular, the expression of genes containing the most recent N-LTRr insertions is enriched in the brain, especially in undifferentiated neurons, and these genes associate in networks related to neuron maturation and migration. Additionally, we identified candidate N-LTRr insertions that have likely produced new functional variants exclusive to modern humans, whose genomic loci show traces of positive selection. Conclusions Our results strongly suggest that N-LTRr impacted our differentiation as a species, most likely inducing an increase in neural complexity, and have been a constant source of genomic variability all throughout the evolution of the human lineage. Electronic supplementary material The online version of this article (10.1186/s13100-018-0133-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Etienne Guichard
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Valentina Peona
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy.,2Department of Evolutionary Biology (EBC), Uppsala University, SE-752 36 Uppsala, Sweden
| | | | - Lucia Abitante
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Evelyn Jagoda
- 4Human Evolutionary Biology, Harvard University, Cambridge, MA 02138 USA
| | - Margherita Musella
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Marco Ricci
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Alejandro Rubio-Roldán
- 5GENYO - Pfizer - Universidad de Granada - Junta de Andalucía Centre for Genomics and Oncological Research, PTS Granada, 18007 Granada, Spain
| | - Stefania Sarno
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Donata Luiselli
- 6Department of Cultural Heritage, University of Bologna, Ravenna Campus, 48121 Ravenna, Italy
| | - Davide Pettener
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
| | - Cristian Taccioli
- 7Department of Animal Medicine, Production and Health, University of Padova, 35020 Legnaro, Pd Italy
| | - Luca Pagani
- 8Department of Biology, University of Padova, 35131 Padova, Italy.,9Estonian Biocentre, Institute of Genomics, University of Tartu, 51010 Tartu, Estonia
| | - Jose Luis Garcia-Perez
- 5GENYO - Pfizer - Universidad de Granada - Junta de Andalucía Centre for Genomics and Oncological Research, PTS Granada, 18007 Granada, Spain.,MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine (IGMM), University of Edinburgh, Western General Hospital, Edinburgh, EH4 2XU UK
| | - Alessio Boattini
- 1Department of Biological, Geological and Environmental Sciences, University of Bologna, 40126 Bologna, Italy
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11
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ALUminating the Path of Atherosclerosis Progression: Chaos Theory Suggests a Role for Alu Repeats in the Development of Atherosclerotic Vascular Disease. Int J Mol Sci 2018; 19:ijms19061734. [PMID: 29895733 PMCID: PMC6032270 DOI: 10.3390/ijms19061734] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 06/04/2018] [Accepted: 06/09/2018] [Indexed: 12/12/2022] Open
Abstract
Atherosclerosis (ATH) and coronary artery disease (CAD) are chronic inflammatory diseases with an important genetic background; they derive from the cumulative effect of multiple common risk alleles, most of which are located in genomic noncoding regions. These complex diseases behave as nonlinear dynamical systems that show a high dependence on their initial conditions; thus, long-term predictions of disease progression are unreliable. One likely possibility is that the nonlinear nature of ATH could be dependent on nonlinear correlations in the structure of the human genome. In this review, we show how chaos theory analysis has highlighted genomic regions that have shared specific structural constraints, which could have a role in ATH progression. These regions were shown to be enriched with repetitive sequences of the Alu family, genomic parasites that have colonized the human genome, which show a particular secondary structure and are involved in the regulation of gene expression. Here, we show the impact of Alu elements on the mechanisms that regulate gene expression, especially highlighting the molecular mechanisms via which the Alu elements alter the inflammatory response. We devote special attention to their relationship with the long noncoding RNA (lncRNA); antisense noncoding RNA in the INK4 locus (ANRIL), a risk factor for ATH; their role as microRNA (miRNA) sponges; and their ability to interfere with the regulatory circuitry of the (nuclear factor kappa B) NF-κB response. We aim to characterize ATH as a nonlinear dynamic system, in which small initial alterations in the expression of a number of repetitive elements are somehow amplified to reach phenotypic significance.
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12
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Navarrete HP, Soler LH, Mares RE, Ramos MA. Frequency of Alu insertions within the ACE and PR loci in Northwestern Mexicans. BMC Res Notes 2017; 10:339. [PMID: 28750672 PMCID: PMC5530943 DOI: 10.1186/s13104-017-2673-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 07/22/2017] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Presently, non-LTR retrotransposons are the most active mobile elements in the human genome. Among these, Alu elements are highly represented in the modern population. Worldwide, distribution of Alu polymorphisms (insertion/deletion; I/D) shows variability between different populations. Two Alu insertion loci, ACE and PR, are significant biomarkers that have served in several genotype-phenotype association studies. In Mexico, studies concerning the frequency of these biomarkers have been conducted mainly in subpopulations from central and southern regions. Here, we screened a population sample of the northwestern region to gain further knowledge regarding the prevalence of Alu polymorphisms within ACE and PR loci. RESULTS For ACE locus, the observed genotype frequencies were 26.5, 51.0 and 22.5% for II, ID, and DD, respectively; and allelic frequencies for I and D were 52 and 48%. Whereas respective genotype frequencies for PR locus were 2.7, 26.5 and 70.8%, and the corresponding allele frequencies were 16 and 84%. Furthermore, the insertion frequency within ACE locus was similar between central, western and northwestern subpopulations, and rather higher in southeastern subpopulation (p < 0.05). Although the occurrence of Alu polymorphisms within PR locus has not been widely examined, the insertion frequency was higher in northwestern subpopulation, as compared with western and southeastern subpopulations (p < 0.05). Based on the frequency of Alu insertions found in ACE and PR loci, subpopulations from the northwestern, western and central regions share a common genetic origin, but apparently not with the subpopulation from the southeastern region, in accordance with the notion that assumes the existence of a broad genomic diversity in the Mexican population. In addition, the high prevalence of Alu insertions reveals their potential application as biomarkers with prognostic value for the associated diseases; e.g., as part of the standard protocols for clinical diagnosis.
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Affiliation(s)
- Hilda P Navarrete
- Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad 14418, Parque Industrial Internacional, 22390, Tijuana, BCN, Mexico
| | - Linda H Soler
- Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad 14418, Parque Industrial Internacional, 22390, Tijuana, BCN, Mexico
| | - Rosa E Mares
- Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad 14418, Parque Industrial Internacional, 22390, Tijuana, BCN, Mexico
| | - Marco A Ramos
- Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad 14418, Parque Industrial Internacional, 22390, Tijuana, BCN, Mexico.
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Alu-miRNA interactions modulate transcript isoform diversity in stress response and reveal signatures of positive selection. Sci Rep 2016; 6:32348. [PMID: 27586304 PMCID: PMC5009348 DOI: 10.1038/srep32348] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 08/01/2016] [Indexed: 02/07/2023] Open
Abstract
Primate-specific Alus harbor different regulatory features, including miRNA targets. In this study, we provide evidence for miRNA-mediated modulation of transcript isoform levels during heat-shock response through exaptation of Alu-miRNA sites in mature mRNA. We performed genome-wide expression profiling coupled with functional validation of miRNA target sites within exonized Alus, and analyzed conservation of these targets across primates. We observed that two miRNAs (miR-15a-3p and miR-302d-3p) elevated in stress response, target RAD1, GTSE1, NR2C1, FKBP9 and UBE2I exclusively within Alu. These genes map onto the p53 regulatory network. Ectopic overexpression of miR-15a-3p downregulates GTSE1 and RAD1 at the protein level and enhances cell survival. This Alu-mediated fine-tuning seems to be unique to humans as evident from the absence of orthologous sites in other primate lineages. We further analyzed signatures of selection on Alu-miRNA targets in the genome, using 1000 Genomes Phase-I data. We found that 198 out of 3177 Alu-exonized genes exhibit signatures of selection within Alu-miRNA sites, with 60 of them containing SNPs supported by multiple evidences (global-FST > 0.3, pair-wise-FST > 0.5, Fay-Wu’s H < −20, iHS > 2.0, high ΔDAF) and implicated in p53 network. We propose that by affecting multiple genes, Alu-miRNA interactions have the potential to facilitate population-level adaptations in response to environmental challenges.
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Pickl JMA, Kamel W, Ciftci S, Punga T, Akusjärvi G. Opposite expression of CYP51A1 and its natural antisense transcript AluCYP51A1 in adenovirus type 37 infected retinal pigmented epithelial cells. FEBS Lett 2015; 589:1383-8. [PMID: 25907535 DOI: 10.1016/j.febslet.2015.04.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/26/2015] [Accepted: 04/10/2015] [Indexed: 11/29/2022]
Abstract
Cytochrome P450 family member CYP51A1 is a key enzyme in cholesterol biosynthesis whose deregulation is implicated in numerous diseases, including retinal degeneration. Here we describe that HAdV-37 infection leads to downregulation of CYP51A1 expression and overexpression of its antisense non-coding Alu element (AluCYP51A1) in retinal pigment epithelium (RPE) cells. This change in gene expression is associated with a reversed accumulation of a positive histone mark at the CYP51A1 and AluCYP51A1 promoters. Further, transient AluCYP51A1 RNA overexpression correlates with reduced CYP51A1 mRNA accumulation. Collectively, our data suggest that AluCYP51A1 might control CYP51A1 gene expression in HAdV-37-infected RPE cells.
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Affiliation(s)
- Julia Maria Anna Pickl
- Department of Medical Biochemistry and Microbiology, Uppsala University, Husargatan 3, BMC, Box 582, 75123 Uppsala, Sweden
| | - Wael Kamel
- Department of Medical Biochemistry and Microbiology, Uppsala University, Husargatan 3, BMC, Box 582, 75123 Uppsala, Sweden
| | - Sibel Ciftci
- Department of Medical Biochemistry and Microbiology, Uppsala University, Husargatan 3, BMC, Box 582, 75123 Uppsala, Sweden
| | - Tanel Punga
- Department of Medical Biochemistry and Microbiology, Uppsala University, Husargatan 3, BMC, Box 582, 75123 Uppsala, Sweden
| | - Göran Akusjärvi
- Department of Medical Biochemistry and Microbiology, Uppsala University, Husargatan 3, BMC, Box 582, 75123 Uppsala, Sweden.
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Lee KJ, Conley AB, Lunyak VV, Jordan IK. Do human transposable element small RNAs serve primarily as genome defenders or genome regulators? Mob Genet Elements 2014; 2:19-25. [PMID: 22754749 PMCID: PMC3383446 DOI: 10.4161/mge.19031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
It is currently thought that small RNA (sRNA) based repression mechanisms are primarily employed to mitigate the mutagenic threat posed by the activity of transposable elements (TEs). This can be achieved by the sRNA guided processing of TE transcripts via Dicer-dependent (e.g., siRNA) or Dicer-independent (e.g., piRNA) mechanisms. For example, potentially active human L1 elements are silenced by mRNA cleavage induced by element encoded siRNAs, leading to a negative correlation between element mRNA and siRNA levels. On the other hand, there is emerging evidence that TE derived sRNAs can also be used to regulate the host genome. Here, we evaluated these two hypotheses for human TEs by comparing the levels of TE derived mRNA and TE sRNA across six tissues. The genome defense hypothesis predicts a negative correlation between TE mRNA and TE sRNA levels, whereas the genome regulatory hypothesis predicts a positive correlation. On average, TE mRNA and TE sRNA levels are positively correlated across human tissues. These correlations are higher than seen for human genes or for randomly permuted control data sets. Overall, Alu subfamilies show the highest positive correlations of element mRNA and sRNA levels across tissues, although a few of the youngest, and potentially most active, Alu subfamilies do show negative correlations. Thus, Alu derived sRNAs may be related to both genome regulation and genome defense. These results are inconsistent with a simple model whereby TE derived sRNAs reduce levels of standing TE mRNA via transcript cleavage, and suggest that human cells efficiently process TE transcripts into sRNA based on the available message levels. This may point to a widespread role for processed TE transcripts in genome regulation or to alternative roles of TE-to-sRNA processing including the mitigation of TE transcript cytotoxicity.
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Abstract
A major biomedical advance from recent years was the finding that gene expression and phenotypic traits may be shaped by potentially reversible and heritable modifications that occur without altering the sequence of the nucleotides, and became known as epigenetic changes. The term 'epigenetics' dates back to the 1940s, when it was first used in context of cellular differentiation decisions that are made during development. Since then, our understanding of epigenetic modifications that govern development and disease expanded considerably. The contribution of epigenetic changes to shaping phenotypes brings at least two major clinically relevant benefits. One of these, stemming from the reversibility of epigenetic changes, involves the possibility to therapeutically revert epigenetic marks to re-establish prior gene expression patterns. The strength and the potential of this strategy are illustrated by the first four epigenetic drugs that were approved in recent years and by the additional candidates that are at various stages in preclinical studies and clinical trials. The second particularity is the finding that epigenetic changes precede the appearance of histopathological modifications. This has the potential to facilitate the emergence of epigenetic biomarkers, some of which already entered the clinical arena, catalysing a major shift in prophylactic and therapeutic strategies, and promising to fill a decades-old gap in preventive medicine.
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Affiliation(s)
- R A Stein
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
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He S, Gu W, Li Y, Zhu H. ANRIL/CDKN2B-AS shows two-stage clade-specific evolution and becomes conserved after transposon insertions in simians. BMC Evol Biol 2013; 13:247. [PMID: 24225082 PMCID: PMC3831594 DOI: 10.1186/1471-2148-13-247] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 11/08/2013] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Many long non-coding RNA (lncRNA) genes identified in mammals have multiple exons and functional domains, allowing them to bind to polycomb proteins, DNA methyltransferases, and specific DNA sequences to regulate genome methylation. Little is known about the origin and evolution of lncRNAs. ANRIL/CDKN2B-AS consists of 19 exons on human chromosome 9p21 and regulates the expression of three cyclin-dependent kinase inhibitors (CDKN2A/ARF/CDKN2B). RESULTS ANRIL/CDKN2B-AS originated in placental mammals, obtained additional exons during mammalian evolution but gradually lost them during rodent evolution, and reached 19 exons only in simians. ANRIL lacks splicing signals in mammals. In simians, multiple transposons were inserted and transformed into exons of the ANRIL gene, after which ANRIL became highly conserved. A further survey reveals that multiple transposons exist in many lncRNAs. CONCLUSIONS ANRIL shows a two-stage, clade-specific evolutionary process and is fully developed only in simians. The domestication of multiple transposons indicates an impressive pattern of "evolutionary tinkering" and is likely to be important for ANRIL's structure and function. The evolution of lncRNAs and that of transposons may be highly co-opted in primates. Many lncRNAs may be functional only in simians.
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Affiliation(s)
| | | | | | - Hao Zhu
- Bioinformatics Section, School of Basic Medical Sciences, Southern Medical University, Shatai Road, Guangzhou 510515, China.
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McCarthy MM, Nugent BM. Epigenetic contributions to hormonally-mediated sexual differentiation of the brain. J Neuroendocrinol 2013; 25:1133-40. [PMID: 23919286 PMCID: PMC5330673 DOI: 10.1111/jne.12072] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 06/18/2013] [Accepted: 06/29/2013] [Indexed: 12/28/2022]
Abstract
It has been long established that hormones exert enduring influences on the developing brain that direct the reproductive response in adulthood, although the cellular mechanisms by which organisational effects are maintained have not been determined satisfactorily. Recent interest in epigenetic modifications to the nervous system has highlighted the potential for hormone-induced changes to the genome that could endure for the lifespan but not be transmitted to the next generation. Preliminary evidence suggests that this is indeed possible because sex differences in the histone code and in the methylation of CpGs in the promoters of specific genes have been identified and, at times, functionally correlated with behaviour. The present review provides an overview of epigenetic processes and discusses the current state-of-the-art, and also identifies future directions.
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Affiliation(s)
- M M McCarthy
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD, USA
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Mandal AK, Pandey R, Jha V, Mukerji M. Transcriptome-wide expansion of non-coding regulatory switches: evidence from co-occurrence of Alu exonization, antisense and editing. Nucleic Acids Res 2013; 41:2121-37. [PMID: 23303787 PMCID: PMC3575813 DOI: 10.1093/nar/gks1457] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 12/13/2012] [Accepted: 12/13/2012] [Indexed: 12/18/2022] Open
Abstract
Non-coding RNAs from transposable elements of human genome are gaining prominence in modulating transcriptome dynamics. Alu elements, as exonized, edited and antisense components within same transcripts could create novel regulatory switches in response to different transcriptional cues. We provide the first evidence for co-occurrences of these events at transcriptome-wide scale through integrative analysis of data sets across diverse experimental platforms and tissues. This involved the following: (i) positional anchoring of Alu exonization events in the UTRs and CDS of 4663 transcript isoforms from RefSeq mRNAs and (ii) mapping on to them A→I editing events inferred from ∼7 million ESTs from dbEST and antisense transcripts identified from virtual serial analysis of gene expression tags represented in Cancer Genome Anatomy Project next-generation sequencing data sets across 20 tissues. We observed significant enrichment of these events in the 3'UTR as well as positional preference within the embedded Alus. More than 300 genes had co-occurrence of all these events at the exon level and were significantly enriched in apoptosis and lysosomal processes. Further, we demonstrate functional evidence of such dynamic interactions between Alu-mediated events in a time series data from Integrated Personal Omics Profiling during recovery from a viral infection. Such 'single transcript-multiple fate' opportunity facilitated by Alu elements may modulate transcriptional response, especially during stress.
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Affiliation(s)
- Amit K. Mandal
- GN Ramachandran Knowledge Centre for Genome Informatics, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India and Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India
| | - Rajesh Pandey
- GN Ramachandran Knowledge Centre for Genome Informatics, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India and Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India
| | - Vineet Jha
- GN Ramachandran Knowledge Centre for Genome Informatics, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India and Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India
| | - Mitali Mukerji
- GN Ramachandran Knowledge Centre for Genome Informatics, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India and Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi-110007, India
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Rebollo R, Romanish MT, Mager DL. Transposable elements: an abundant and natural source of regulatory sequences for host genes. Annu Rev Genet 2012; 46:21-42. [PMID: 22905872 DOI: 10.1146/annurev-genet-110711-155621] [Citation(s) in RCA: 352] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The fact that transposable elements (TEs) can influence host gene expression was first recognized more than 50 years ago. However, since that time, TEs have been widely regarded as harmful genetic parasites-selfish elements that are rarely co-opted by the genome to serve a beneficial role. Here, we survey recent findings that relate to TE impact on host genes and remind the reader that TEs, in contrast to other noncoding parts of the genome, are uniquely suited to gene regulatory functions. We review recent studies that demonstrate the role of TEs in establishing and rewiring gene regulatory networks and discuss the overall ubiquity of exaptation. We suggest that although individuals within a population can be harmed by the deleterious effects of new TE insertions, the presence of TE sequences in a genome is of overall benefit to the population.
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Affiliation(s)
- Rita Rebollo
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, Canada.
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Pandey R, Mandal AK, Jha V, Mukerji M. Heat shock factor binding in Alu repeats expands its involvement in stress through an antisense mechanism. Genome Biol 2011; 12:R117. [PMID: 22112862 PMCID: PMC3334603 DOI: 10.1186/gb-2011-12-11-r117] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 11/09/2011] [Accepted: 11/23/2011] [Indexed: 01/22/2023] Open
Abstract
Background Alu RNAs are present at elevated levels in stress conditions and, consequently, Alu repeats are increasingly being associated with the physiological stress response. Alu repeats are known to harbor transcription factor binding sites that modulate RNA pol II transcription and Alu RNAs act as transcriptional co-repressors through pol II binding in the promoter regions of heat shock responsive genes. An observation of a putative heat shock factor (HSF) binding site in Alu led us to explore whether, through HSF binding, these elements could further contribute to the heat shock response repertoire. Results Alu density was significantly enriched in transcripts that are down-regulated following heat shock recovery in HeLa cells. ChIP analysis confirmed HSF binding to a consensus motif exhibiting positional conservation across various Alu subfamilies, and reporter constructs demonstrated a sequence-specific two-fold induction of these sites in response to heat shock. These motifs were over-represented in the genic regions of down-regulated transcripts in antisense oriented Alus. Affymetrix Exon arrays detected antisense signals in a significant fraction of the down-regulated transcripts, 50% of which harbored HSF sites within 5 kb. siRNA knockdown of the selected antisense transcripts led to the over-expression, following heat shock, of their corresponding down-regulated transcripts. The antisense transcripts were significantly enriched in processes related to RNA pol III transcription and the TFIIIC complex. Conclusions We demonstrate a non-random presence of Alu repeats harboring HSF sites in heat shock responsive transcripts. This presence underlies an antisense-mediated mechanism that represents a novel component of Alu and HSF involvement in the heat shock response.
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Affiliation(s)
- Rajesh Pandey
- Genomics and Molecular Medicine, Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research (CSIR-IGIB), Delhi- India
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