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Tshilenge KT, Bons J, Aguirre CG, Geronimo-Olvera C, Shah S, Rose J, Gerencser AA, Mak SK, Ehrlich ME, Bragg DC, Schilling B, Ellerby LM. Proteomic analysis of X-linked dystonia parkinsonism disease striatal neurons reveals altered RNA metabolism and splicing. Neurobiol Dis 2024; 190:106367. [PMID: 38042508 PMCID: PMC11103251 DOI: 10.1016/j.nbd.2023.106367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/16/2023] [Accepted: 11/27/2023] [Indexed: 12/04/2023] Open
Abstract
X-linked dystonia-parkinsonism (XDP) is a rare neurodegenerative disease endemic to the Philippines. The genetic cause for XDP is an insertion of a SINE-VNTR-Alu (SVA)-type retrotransposon within intron 32 of TATA-binding protein associated factor 1 (TAF1) that causes an alteration of TAF1 splicing, partial intron retention, and decreased transcription. Although TAF1 is expressed in all organs, medium spiny neurons (MSNs) within the striatum are one of the cell types most affected in XDP. To define how mutations in the TAF1 gene lead to MSN vulnerability, we carried out a proteomic analysis of human XDP patient-derived neural stem cells (NSCs) and MSNs derived from induced pluripotent stem cells. NSCs and MSNs were grown in parallel and subjected to quantitative proteomic analysis in data-independent acquisition mode on the Orbitrap Eclipse Tribrid mass spectrometer. Subsequent functional enrichment analysis demonstrated that neurodegenerative disease-related pathways, such as Huntington's disease, spinocerebellar ataxia, cellular senescence, mitochondrial function and RNA binding metabolism, were highly represented. We used weighted coexpression network analysis (WGCNA) of the NSC and MSN proteomic data set to uncover disease-driving network modules. Three of the modules significantly correlated with XDP genotype when compared to the non-affected control and were enriched for DNA helicase and nuclear chromatin assembly, mitochondrial disassembly, RNA location and mRNA processing. Consistent with aberrant mRNA processing, we found splicing and intron retention of TAF1 intron 32 in XDP MSN. We also identified TAF1 as one of the top enriched transcription factors, along with YY1, ATF2, USF1 and MYC. Notably, YY1 has been implicated in genetic forms of dystonia. Overall, our proteomic data set constitutes a valuable resource to understand mechanisms relevant to TAF1 dysregulation and to identify new therapeutic targets for XDP.
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Affiliation(s)
| | - Joanna Bons
- The Buck Institute for Research on Aging, Novato, California 94945, USA
| | - Carlos Galicia Aguirre
- The Buck Institute for Research on Aging, Novato, California 94945, USA; University of Southern California, Leonard Davis School of Gerontology, 3715 McClintock Ave, Los Angeles, CA 90893, USA
| | | | - Samah Shah
- The Buck Institute for Research on Aging, Novato, California 94945, USA
| | - Jacob Rose
- The Buck Institute for Research on Aging, Novato, California 94945, USA
| | - Akos A Gerencser
- The Buck Institute for Research on Aging, Novato, California 94945, USA
| | - Sally K Mak
- The Buck Institute for Research on Aging, Novato, California 94945, USA
| | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - D Cristopher Bragg
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, The Collaborative Center for X-linked Dystonia-Parkinsonism, Massachusetts General Hospital, Charlestown, MA, USA
| | - Birgit Schilling
- The Buck Institute for Research on Aging, Novato, California 94945, USA; University of Southern California, Leonard Davis School of Gerontology, 3715 McClintock Ave, Los Angeles, CA 90893, USA.
| | - Lisa M Ellerby
- The Buck Institute for Research on Aging, Novato, California 94945, USA; University of Southern California, Leonard Davis School of Gerontology, 3715 McClintock Ave, Los Angeles, CA 90893, USA.
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Liao X, Zhu W, Zhou J, Li H, Xu X, Zhang B, Gao X. Repetitive DNA sequence detection and its role in the human genome. Commun Biol 2023; 6:954. [PMID: 37726397 PMCID: PMC10509279 DOI: 10.1038/s42003-023-05322-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/04/2023] [Indexed: 09/21/2023] Open
Abstract
Repetitive DNA sequences playing critical roles in driving evolution, inducing variation, and regulating gene expression. In this review, we summarized the definition, arrangement, and structural characteristics of repeats. Besides, we introduced diverse biological functions of repeats and reviewed existing methods for automatic repeat detection, classification, and masking. Finally, we analyzed the type, structure, and regulation of repeats in the human genome and their role in the induction of complex diseases. We believe that this review will facilitate a comprehensive understanding of repeats and provide guidance for repeat annotation and in-depth exploration of its association with human diseases.
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Affiliation(s)
- Xingyu Liao
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Wufei Zhu
- Department of Endocrinology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, 443000, Yichang, P.R. China
| | - Juexiao Zhou
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Haoyang Li
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Xiaopeng Xu
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Bin Zhang
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia
| | - Xin Gao
- Computational Bioscience Research Center (CBRC), Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955, Saudi Arabia.
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X-linked dystonia parkinsonism: epidemiology, genetics, clinical features, diagnosis, and treatment. Acta Neurol Belg 2023; 123:45-55. [PMID: 36418540 DOI: 10.1007/s13760-022-02144-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 11/09/2022] [Indexed: 11/27/2022]
Abstract
X-linked dystonia parkinsonism (XDP) is a rare X-linked recessive degenerative movement disorder that only affects Filipino descent, predominantly males. Its underlying cause is associated with the genetic alterations in the TAF1/DYT3 multiple transcription system. SINE-VNTR-Alu (SVA) retrotransposon insertion was suggested to be the responsible genetic mutation. Clinically, it initially presents as focal dystonia and generalizes within years. Parkinsonism arises years later and coexists with dystonia. Nonmotor symptoms like cognitive impairment and mood disorders are also common among XDP patients. XDP diagnosis relies on clinical history and physical examination. On imaging, abnormalities of the striatum, such as atrophy, are widely seen and can explain the clinical presentations with a three-model pathway of the striatum. Treatments aim for symptomatic relief of dystonia and parkinsonism and to prevent complications. Oral medications, chemo-denervation, and surgery are used in XDP patients. This review summarizes the currently important information regarding XDP, providing a synoptic overview and understanding of XDP for future studies.
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Savage AL, Iacoangeli A, Schumann GG, Rubio-Roldan A, Garcia-Perez JL, Al Khleifat A, Koks S, Bubb VJ, Al-Chalabi A, Quinn JP. Characterisation of retrotransposon insertion polymorphisms in whole genome sequencing data from individuals with amyotrophic lateral sclerosis. Gene 2022; 843:146799. [PMID: 35963498 DOI: 10.1016/j.gene.2022.146799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/15/2022] [Accepted: 08/05/2022] [Indexed: 11/15/2022]
Abstract
The genetics of an individual is a crucial factor in understanding the risk of developing the neurodegenerative disease amyotrophic lateral sclerosis (ALS). There is still a large proportion of the heritability of ALS, particularly in sporadic cases, to be understood. Among others, active transposable elements drive inter-individual variability, and in humans long interspersed element 1 (LINE1, L1), Alu and SINE-VNTR-Alu (SVA) retrotransposons are a source of polymorphic insertions in the population. We undertook a pilot study to characterise the landscape of non-reference retrotransposon insertion polymorphisms (non-ref RIPs) in 15 control and 15 ALS individuals' whole genomes from Project MinE, an international project to identify potential genetic causes of ALS. The combination of two bioinformatics tools (mobile element locator tool (MELT) and TEBreak) identified on average 1250 Alu, 232 L1 and 77 SVA non-ref RIPs per genome across the 30 analysed. Further PCR validation of individual polymorphic retrotransposon insertions showed a similar level of accuracy for MELT and TEBreak. Our preliminary study did not identify a specific RIP or a significant difference in the total number of non-ref RIPs in ALS compared to control genomes. The use of multiple bioinformatic tools improved the accuracy of non-ref RIP detection and our study highlights the potential importance of studying these elements further in ALS.
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Affiliation(s)
- Abigail L Savage
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Alfredo Iacoangeli
- Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London SE5 9RT, UK; Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London SE5 8AF, UK
| | - Gerald G Schumann
- Division of Medical Biotechnology, Paul-Ehrlich-Institut, Langen 63225, Germany
| | - Alejandro Rubio-Roldan
- Department of Genomic Medicine and Department of Oncology, GENYO, Centre for Genomics & Oncology, PTS Granada, 18007, Spain
| | - Jose L Garcia-Perez
- Department of Genomic Medicine and Department of Oncology, GENYO, Centre for Genomics & Oncology, PTS Granada, 18007, Spain; MRC-HGU Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Ahmad Al Khleifat
- Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London SE5 9RT, UK
| | - Sulev Koks
- Perron Institute for Neurological and Translational Science, Perth, Western Australia 6009, Australia; Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, Western Australia 6150, Australia
| | - Vivien J Bubb
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Ammar Al-Chalabi
- Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London SE5 9RT, UK; Department of Neurology, King's College Hospital, London SE5 9RS, UK
| | - John P Quinn
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK.
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Transposable Elements and Human Diseases: Mechanisms and Implication in the Response to Environmental Pollutants. Int J Mol Sci 2022; 23:ijms23052551. [PMID: 35269693 PMCID: PMC8910135 DOI: 10.3390/ijms23052551] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 02/06/2023] Open
Abstract
Transposable elements (TEs) are recognized as major players in genome plasticity and evolution. The high abundance of TEs in the human genome, especially the Alu and Long Interspersed Nuclear Element-1 (LINE-1) repeats, makes them responsible for the molecular origin of several diseases. This involves several molecular mechanisms that are presented in this review: insertional mutation, DNA recombination and chromosomal rearrangements, modification of gene expression, as well as alteration of epigenetic regulations. This literature review also presents some of the more recent and/or more classical examples of human diseases in which TEs are involved. Whether through insertion of LINE-1 or Alu elements that cause chromosomal rearrangements, or through epigenetic modifications, TEs are widely implicated in the origin of human cancers. Many other human diseases can have a molecular origin in TE-mediated chromosomal recombination or alteration of gene structure and/or expression. These diseases are very diverse and include hemoglobinopathies, metabolic and neurological diseases, and common diseases. Moreover, TEs can also have an impact on aging. Finally, the exposure of individuals to stresses and environmental contaminants seems to have a non-negligible impact on the epigenetic derepression and mobility of TEs, which can lead to the development of diseases. Thus, improving our knowledge of TEs may lead to new potential diagnostic markers of diseases.
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Pozojevic J, Algodon SM, Cruz JN, Trinh J, Brüggemann N, Laß J, Grütz K, Schaake S, Tse R, Yumiceba V, Kruse N, Schulz K, Sreenivasan VKA, Rosales RL, Jamora RDG, Diesta CCE, Matschke J, Glatzel M, Seibler P, Händler K, Rakovic A, Kirchner H, Spielmann M, Kaiser FJ, Klein C, Westenberger A. Transcriptional Alterations in X-Linked Dystonia–Parkinsonism Caused by the SVA Retrotransposon. Int J Mol Sci 2022; 23:ijms23042231. [PMID: 35216353 PMCID: PMC8875906 DOI: 10.3390/ijms23042231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/09/2022] [Accepted: 02/14/2022] [Indexed: 02/05/2023] Open
Abstract
X-linked dystonia–parkinsonism (XDP) is a severe neurodegenerative disorder that manifests as adult-onset dystonia combined with parkinsonism. A SINE-VNTR-Alu (SVA) retrotransposon inserted in an intron of the TAF1 gene reduces its expression and alters splicing in XDP patient-derived cells. As a consequence, increased levels of the TAF1 intron retention transcript TAF1-32i can be found in XDP cells as compared to healthy controls. Here, we investigate the sequence of the deep intronic region included in this transcript and show that it is also present in cells from healthy individuals, albeit in lower amounts than in XDP cells, and that it undergoes degradation by nonsense-mediated mRNA decay. Furthermore, we investigate epigenetic marks (e.g., DNA methylation and histone modifications) present in this intronic region and the spanning sequence. Finally, we show that the SVA evinces regulatory potential, as demonstrated by its ability to repress the TAF1 promoter in vitro. Our results enable a better understanding of the disease mechanisms underlying XDP and transcriptional alterations caused by SVA retrotransposons.
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Affiliation(s)
- Jelena Pozojevic
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Shela Marie Algodon
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Joseph Neos Cruz
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Joanne Trinh
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Norbert Brüggemann
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
- Department of Neurology, University Hospital Schleswig Holstein, 23538 Lübeck, Germany
| | - Joshua Laß
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Karen Grütz
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Susen Schaake
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Ronnie Tse
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Veronica Yumiceba
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Nathalie Kruse
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Kristin Schulz
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Varun K. A. Sreenivasan
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Raymond L. Rosales
- The Hospital Neuroscience Institute, Department of Neurology and Psychiatry and The FMS-Research Center for Health Sciences, University of Santo Tomas, Manila 1008, Philippines;
| | - Roland Dominic G. Jamora
- Department of Neurosciences, College of Medicine-Philippine General Hospital, University of the Philippines Manila, Manila 1000, Philippines;
| | - Cid Czarina E. Diesta
- Department of Neurosciences, Movement Disorders Clinic, Makati Medical Center, Makati City 1229, Philippines;
| | - Jakob Matschke
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (J.M.); (M.G.)
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (J.M.); (M.G.)
| | - Philip Seibler
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Kristian Händler
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Aleksandar Rakovic
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
| | - Henriette Kirchner
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
| | - Malte Spielmann
- Institute of Human Genetics, University of Lübeck, 23538 Lübeck, Germany; (V.Y.); (N.K.); (K.S.); (V.K.A.S.); (K.H.); (H.K.); (M.S.)
- Human Molecular Genomics Group, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Lübeck/Kiel, 23538 Lübeck, Germany
| | - Frank J. Kaiser
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, 45147 Essen, Germany;
- Essener Zentrum für Seltene Erkrankungen, Universitätsmedizin Essen, 45147 Essen, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
- Correspondence: (C.K.); (A.W.)
| | - Ana Westenberger
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (S.M.A.); (J.N.C.); (J.T.); (N.B.); (J.L.); (K.G.); (S.S.); (R.T.); (P.S.); (A.R.)
- Correspondence: (C.K.); (A.W.)
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Pozojevic J, Cruz JN, Westenberger A. X-linked dystonia-parkinsonism: over and above a repeat disorder. MED GENET-BERLIN 2021; 33:319-324. [PMID: 38835428 PMCID: PMC11006257 DOI: 10.1515/medgen-2021-2105] [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: 04/29/2021] [Accepted: 11/24/2021] [Indexed: 06/06/2024]
Abstract
X-linked dystonia-parkinsonism (XDP) is an adult-onset neurodegenerative movement disorder, caused by a founder retrotransposon insertion in an intron of the TAF1 gene. This insertion contains a polymorphic hexanucleotide repeat (CCCTCT)n, the length of which inversely correlates with the age at disease onset (AAO) and other clinical parameters, aligning XDP with repeat expansion disorders. Nevertheless, many other pathogenic mechanisms are conceivably at play in XDP, indicating that in contrast to other repeat disorders, the (CCCTCT)n repeat may not be the actual (or only) disease cause. Here, we summarize and discuss genetic and molecular aspects of XDP, highlighting the role of the hexanucleotide repeat in age-related disease penetrance and expressivity.
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Affiliation(s)
- Jelena Pozojevic
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
- Institute of Human Genetics, University of Lübeck, Lübeck, Germany
| | - Joseph Neos Cruz
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
- Disease Molecular Biology and Epigenetics Laboratory, University of the Philippines Diliman, Quezon City, Philippines
| | - Ana Westenberger
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
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Expression Quantitative Trait Loci (eQTLs) Associated with Retrotransposons Demonstrate their Modulatory Effect on the Transcriptome. Int J Mol Sci 2021; 22:ijms22126319. [PMID: 34204806 PMCID: PMC8231655 DOI: 10.3390/ijms22126319] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/03/2021] [Accepted: 06/10/2021] [Indexed: 12/26/2022] Open
Abstract
Transposable elements (TEs) are repetitive elements that belong to a variety of functional classes and have an important role in shaping genome evolution. Around 50% of the human genome contains TEs, and they have been termed the "dark matter" of the genome because relatively little is known about their function. While TEs have been shown to participate in aberrant gene regulation and the pathogenesis of diseases, only a few studies have explored the systemic effect of TEs on gene expression. In the present study, we analysed whole genome sequences and blood whole transcriptome data from 570 individuals within the Parkinson's Progressive Markers Initiative (PPMI) cohort to identify expression quantitative trait loci (eQTL) regulating genome-wide gene expression associated with TEs. We identified 2132 reference TEs that were polymorphic for their presence or absence in our study cohort. The presence or absence of the TE element could change the expression of the gene or gene clusters from zero to tens of thousands of copies of RNA. The main finding is that many TEs possess very strong regulatory effects, and they have the potential to modulate large genetic networks with hundreds of target genes over the genome. We illustrate the plethora of regulatory mechanisms using examples of their action at the HLA gene cluster and data showing different TEs' convergence to modulate WFS1 gene expression. In conclusion, the presence or absence of polymorphisms of TEs has an eminent genome-wide regulatory function with large effect size at the level of the whole transcriptome. The role of TEs in explaining, in part, the missing heritability for complex traits is convincing and should be considered.
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