1
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Chung TH, Zhuravskaya A, Makeyev EV. Regulation potential of transcribed simple repeated sequences in developing neurons. Hum Genet 2024; 143:875-895. [PMID: 38153590 PMCID: PMC11294396 DOI: 10.1007/s00439-023-02626-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 11/28/2023] [Indexed: 12/29/2023]
Abstract
Simple repeated sequences (SRSs), defined as tandem iterations of microsatellite- to satellite-sized DNA units, occupy a substantial part of the human genome. Some of these elements are known to be transcribed in the context of repeat expansion disorders. Mounting evidence suggests that the transcription of SRSs may also contribute to normal cellular functions. Here, we used genome-wide bioinformatics approaches to systematically examine SRS transcriptional activity in cells undergoing neuronal differentiation. We identified thousands of long noncoding RNAs containing >200-nucleotide-long SRSs (SRS-lncRNAs), with hundreds of these transcripts significantly upregulated in the neural lineage. We show that SRS-lncRNAs often originate from telomere-proximal regions and that they have a strong potential to form multivalent contacts with a wide range of RNA-binding proteins. Our analyses also uncovered a cluster of neurally upregulated SRS-lncRNAs encoded in a centromere-proximal part of chromosome 9, which underwent an evolutionarily recent segmental duplication. Using a newly established in vitro system for rapid neuronal differentiation of induced pluripotent stem cells, we demonstrate that at least some of the bioinformatically predicted SRS-lncRNAs, including those encoded in the segmentally duplicated part of chromosome 9, indeed increase their expression in developing neurons to readily detectable levels. These and other lines of evidence suggest that many SRSs may be expressed in a cell type and developmental stage-specific manner, providing a valuable resource for further studies focused on the functional consequences of SRS-lncRNAs in the normal development of the human brain, as well as in the context of neurodevelopmental disorders.
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Affiliation(s)
- Tek Hong Chung
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK
| | - Anna Zhuravskaya
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK
| | - Eugene V Makeyev
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK.
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2
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Barutcu AR, Black MB, Samuel R, Slattery S, McMullen PD, Nong A. Integrating gene expression and splicing dynamics across dose-response oxidative modulators. Front Genet 2024; 15:1389095. [PMID: 38846964 PMCID: PMC11155298 DOI: 10.3389/fgene.2024.1389095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/06/2024] [Indexed: 06/09/2024] Open
Abstract
Toxicological risk assessment increasingly utilizes transcriptomics to derive point of departure (POD) and modes of action (MOA) for chemicals. One essential biological process that allows a single gene to generate several different RNA isoforms is called alternative splicing. To comprehensively assess the role of splicing dysregulation in toxicological evaluation and elucidate its potential as a complementary endpoint, we performed RNA-seq on A549 cells treated with five oxidative stress modulators across a wide dose range. Differential gene expression (DGE) showed limited pathway enrichment except at high concentrations. However, alternative splicing analysis revealed variable intron retention events affecting diverse pathways for all chemicals in the absence of significant expression changes. For instance, diazinon elicited negligible gene expression changes but progressive increase in the number of intron retention events, suggesting splicing alterations precede expression responses. Benchmark dose modeling of intron retention data highlighted relevant pathways overlooked by expression analysis. Systematic integration of splicing datasets should be a useful addition to the toxicogenomic toolkit. Combining both modalities paint a more complete picture of transcriptomic dose-responses. Overall, evaluating intron retention dynamics afforded by toxicogenomics may provide biomarkers that can enhance chemical risk assessment and regulatory decision making. This work highlights splicing-aware toxicogenomics as a possible additional tool for examining cellular responses.
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3
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Zhong Y, Yang Y, Wang X, Ren B, Wang X, Shan G, Chen L. Systematic identification and characterization of exon-intron circRNAs. Genome Res 2024; 34:376-393. [PMID: 38609186 PMCID: PMC11067877 DOI: 10.1101/gr.278590.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 03/07/2024] [Indexed: 04/14/2024]
Abstract
Exon-intron circRNAs (EIciRNAs) are a circRNA subclass with retained introns. Global features of EIciRNAs remain largely unexplored, mainly owing to the lack of bioinformatic tools. The regulation of intron retention (IR) in EIciRNAs and the associated functionality also require further investigation. We developed a framework, FEICP, which efficiently detected EIciRNAs from high-throughput sequencing (HTS) data. EIciRNAs are distinct from exonic circRNAs (EcircRNAs) in aspects such as with larger length, localization in the nucleus, high tissue specificity, and enrichment mostly in the brain. Deep learning analyses revealed that compared with regular introns, the retained introns of circRNAs (CIRs) are shorter in length, have weaker splice site strength, and have higher GC content. Compared with retained introns in linear RNAs (LIRs), CIRs are more likely to form secondary structures and show greater sequence conservation. CIRs are closer to the 5'-end, whereas LIRs are closer to the 3'-end of transcripts. EIciRNA-generating genes are more actively transcribed and associated with epigenetic marks of gene activation. Computational analyses and genome-wide CRISPR screening revealed that SRSF1 binds to CIRs and inhibits the biogenesis of most EIciRNAs. SRSF1 regulates the biogenesis of EIciLIMK1, which enhances the expression of LIMK1 in cis to boost neuronal differentiation, exemplifying EIciRNA physiological function. Overall, our study has developed the FEICP pipeline to identify EIciRNAs from HTS data, and reveals multiple features of CIRs and EIciRNAs. SRSF1 has been identified to regulate EIciRNA biogenesis. EIciRNAs and the regulation of EIciRNA biogenesis play critical roles in neuronal differentiation.
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Affiliation(s)
- Yinchun Zhong
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Yan Yang
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Clinical Laboratory, The First Affiliated Hospital of USTC, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Xiaolin Wang
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Clinical Laboratory, The First Affiliated Hospital of USTC, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Bingbing Ren
- Department of Pulmonary and Critical Care Medicine, Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China
| | - Xueren Wang
- Department of Anesthesiology, Shanxi Bethune Hospital, Taiyuan 030032, China;
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Ge Shan
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Clinical Laboratory, The First Affiliated Hospital of USTC, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230027, China;
| | - Liang Chen
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei 230027, China
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4
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Citores L, Ragucci S, Gay CC, Russo R, Chambery A, Di Maro A, Iglesias R, Ferreras JM. Edodin: A New Type of Toxin from Shiitake Mushroom ( Lentinula edodes) That Inactivates Mammalian Ribosomes. Toxins (Basel) 2024; 16:185. [PMID: 38668610 PMCID: PMC11053714 DOI: 10.3390/toxins16040185] [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: 03/08/2024] [Revised: 04/05/2024] [Accepted: 04/08/2024] [Indexed: 04/29/2024] Open
Abstract
Ribosome-inactivating proteins (RIPs) are a group of proteins with rRNA N-glycosylase activity that irreversibly inhibit protein synthesis and consequently cause cell death. Recently, an RIP called ledodin has been found in shiitake; it is cytotoxic, strongly inhibits protein synthesis, and shows rRNA N-glycosylase activity. In this work, we isolated and characterized a 50 kDa cytotoxic protein from shiitake that we named edodin. Edodin inhibits protein synthesis in a mammalian cell-free system, but not in insect-, yeast-, and bacteria-derived systems. It exhibits rRNA N-glycosylase and DNA-nicking activities, which relate it to plant RIPs. It was also shown to be toxic to HeLa and COLO 320 cells. Its structure is not related to other RIPs found in plants, bacteria, or fungi, but, instead, it presents the characteristic structure of the fold type I of pyridoxal phosphate-dependent enzymes. Homologous sequences have been found in other fungi of the class Agaricomycetes; thus, edodin could be a new type of toxin present in many fungi, some of them edible, which makes them of great interest in health, both for their involvement in food safety and for their potential biomedical and biotechnological applications.
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Affiliation(s)
- Lucía Citores
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain;
| | - Sara Ragucci
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania ‘Luigi Vanvitelli’, Via Vivaldi 43, 81100 Caserta, Italy; (S.R.); (R.R.); (A.C.); (A.D.M.)
| | - Claudia C. Gay
- Laboratory of Protein Research, Institute of Basic and Applied Chemistry of Northeast Argentina (UNNE-CONICET), Faculty of Exact and Natural Sciences and Surveying, Av. Libertad 5470, Corrientes 3400, Argentina;
| | - Rosita Russo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania ‘Luigi Vanvitelli’, Via Vivaldi 43, 81100 Caserta, Italy; (S.R.); (R.R.); (A.C.); (A.D.M.)
| | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania ‘Luigi Vanvitelli’, Via Vivaldi 43, 81100 Caserta, Italy; (S.R.); (R.R.); (A.C.); (A.D.M.)
| | - Antimo Di Maro
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania ‘Luigi Vanvitelli’, Via Vivaldi 43, 81100 Caserta, Italy; (S.R.); (R.R.); (A.C.); (A.D.M.)
| | - Rosario Iglesias
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain;
| | - José M. Ferreras
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain;
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5
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Yang L, Wang M, Wang Y, Zhu Y, Wang J, Wu M, Guo Q, Han X, Pandey V, Wu Z, Lobie PE, Zhu T. LINC00460-FUS-MYC feedback loop drives breast cancer metastasis and doxorubicin resistance. Oncogene 2024; 43:1249-1262. [PMID: 38418543 DOI: 10.1038/s41388-024-02972-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 02/03/2024] [Accepted: 02/07/2024] [Indexed: 03/01/2024]
Abstract
Therapeutic resistance and metastasis largely contribute to mortality from breast cancer and therefore understanding the underlying mechanisms of such remains an urgent challenge. By cross-analysis of TCGA and GEO databases, LINC00460 was identified as an oncogenic long non-coding RNA, highly expressed in Doxorubicin resistant breast cancer. LINC00460 was further demonstrated to promote stem cell-like and epithelial-mesenchymal transition (EMT) characteristics in breast cancer cells. LINC00460 interacts with FUS protein with consequent enhanced stabilization, which further promotes MYC mRNA maturation. LINC00460 expression was transcriptionally enhanced by c-MYC protein, forming a positive feedback loop to promote metastasis and Doxorubicin resistance. LINC00460 depletion in Doxorubicin-resistant breast cancer cells restored sensitivity to Doxorubicin and increased the efficacy of c-MYC inhibitor therapy. Collectively, these findings implicate LINC00460 as a promising prognostic biomarker and potential therapeutic target to overcome Doxorubicin resistance in breast cancer.
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Affiliation(s)
- Leiyan Yang
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Key Laboratory of Immune Response and Immunotherapy, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Miaomiao Wang
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Key Laboratory of Immune Response and Immunotherapy, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Ya Wang
- Institute of Basic Medicine and Cancer, Chinese Academy of Sciences, Hangzhou, 310000, Zhejiang, China
| | - Yong Zhu
- Department of Pathophysiology, School of Basic Medical Sciences, Anhui Medical University, 230032, Hefei, Anhui, China
| | - Jiarui Wang
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Key Laboratory of Immune Response and Immunotherapy, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Mingming Wu
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Key Laboratory of Immune Response and Immunotherapy, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Qianying Guo
- Department of Pathology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Xinghua Han
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Vijay Pandey
- Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China
| | - Zhengsheng Wu
- Department of Pathology, Anhui Medical University, Hefei, 230032, Anhui, China
| | - Peter E Lobie
- Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
- Shenzhen Bay Laboratory, Shenzhen, 518055, China.
| | - Tao Zhu
- Department of Oncology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
- Key Laboratory of Immune Response and Immunotherapy, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
- Shenzhen Bay Laboratory, Shenzhen, 518055, China.
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6
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Werren EA, LaForce GR, Srivastava A, Perillo DR, Li S, Johnson K, Baris S, Berger B, Regan SL, Pfennig CD, de Munnik S, Pfundt R, Hebbar M, Jimenez-Heredia R, Karakoc-Aydiner E, Ozen A, Dmytrus J, Krolo A, Corning K, Prijoles EJ, Louie RJ, Lebel RR, Le TL, Amiel J, Gordon CT, Boztug K, Girisha KM, Shukla A, Bielas SL, Schaffer AE. TREX tetramer disruption alters RNA processing necessary for corticogenesis in THOC6 Intellectual Disability Syndrome. Nat Commun 2024; 15:1640. [PMID: 38388531 PMCID: PMC10884030 DOI: 10.1038/s41467-024-45948-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 02/07/2024] [Indexed: 02/24/2024] Open
Abstract
THOC6 variants are the genetic basis of autosomal recessive THOC6 Intellectual Disability Syndrome (TIDS). THOC6 is critical for mammalian Transcription Export complex (TREX) tetramer formation, which is composed of four six-subunit THO monomers. The TREX tetramer facilitates mammalian RNA processing, in addition to the nuclear mRNA export functions of the TREX dimer conserved through yeast. Human and mouse TIDS model systems revealed novel THOC6-dependent, species-specific TREX tetramer functions. Germline biallelic Thoc6 loss-of-function (LOF) variants result in mouse embryonic lethality. Biallelic THOC6 LOF variants reduce the binding affinity of ALYREF to THOC5 without affecting the protein expression of TREX members, implicating impaired TREX tetramer formation. Defects in RNA nuclear export functions were not detected in biallelic THOC6 LOF human neural cells. Instead, mis-splicing was detected in human and mouse neural tissue, revealing novel THOC6-mediated TREX coordination of mRNA processing. We demonstrate that THOC6 is required for key signaling pathways known to regulate the transition from proliferative to neurogenic divisions during human corticogenesis. Together, these findings implicate altered RNA processing in the developmental biology of TIDS neuropathology.
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Affiliation(s)
- Elizabeth A Werren
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Advanced Precision Medicine Laboratory, The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Geneva R LaForce
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Anshika Srivastava
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Department of Medical Genetics, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, Uttar Pradesh, 226014, India
| | - Delia R Perillo
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Shaokun Li
- Advanced Precision Medicine Laboratory, The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Katherine Johnson
- Advanced Precision Medicine Laboratory, The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Safa Baris
- Division of Pediatric Allergy and Immunology, School of Medicine, Marmara University, Istanbul Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiencies, The Isil Berat Barlan Center for Translational Medicine, Istanbul, 34722, Turkey
| | - Brandon Berger
- Advanced Precision Medicine Laboratory, The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Samantha L Regan
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Christian D Pfennig
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Sonja de Munnik
- Department of Human Genetics, Radboud University Medical Centre Nijmegen, Nijmegen, 6524, the Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Centre Nijmegen, Nijmegen, 6524, the Netherlands
| | - Malavika Hebbar
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, 98195, Seattle, WA, USA
| | - Raúl Jimenez-Heredia
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, 1090, Austria
| | - Elif Karakoc-Aydiner
- Division of Pediatric Allergy and Immunology, School of Medicine, Marmara University, Istanbul Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiencies, The Isil Berat Barlan Center for Translational Medicine, Istanbul, 34722, Turkey
| | - Ahmet Ozen
- Division of Pediatric Allergy and Immunology, School of Medicine, Marmara University, Istanbul Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiencies, The Isil Berat Barlan Center for Translational Medicine, Istanbul, 34722, Turkey
| | - Jasmin Dmytrus
- Research Centre for Molecular Medicine of the Austrian Academy of Sciences, Vienna, 1090, Austria
| | - Ana Krolo
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, 1090, Austria
| | - Ken Corning
- Greenwood Genetic Center, Greenwood, SC, 29646, USA
| | - E J Prijoles
- Greenwood Genetic Center, Greenwood, SC, 29646, USA
| | | | - Robert Roger Lebel
- Section of Medical Genetics, SUNY Upstate Medical University, Syracuse, NY, 13210, USA
| | - Thuy-Linh Le
- Imagine Institute, INSERM U1163, Paris Cité University, Paris, 75015, France
| | - Jeanne Amiel
- Imagine Institute, INSERM U1163, Paris Cité University, Paris, 75015, France
- Service de Médecine Génomique des Maladies Rares, Hôpital Necker-Enfants Malades, AP-HP, Paris, 75015, France
| | | | - Kaan Boztug
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, 1090, Austria
- Research Centre for Molecular Medicine of the Austrian Academy of Sciences, Vienna, 1090, Austria
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, 1090, Austria
- St. Anna Children's Hospital and Children's Cancer Research Institute, Department of Pediatrics, Medical University of Vienna, Vienna, 1090, Austria
| | - Katta M Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, 576104, India
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, 576104, India
| | - Stephanie L Bielas
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
| | - Ashleigh E Schaffer
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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7
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Tao Y, Zhang Q, Wang H, Yang X, Mu H. Alternative splicing and related RNA binding proteins in human health and disease. Signal Transduct Target Ther 2024; 9:26. [PMID: 38302461 PMCID: PMC10835012 DOI: 10.1038/s41392-024-01734-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 12/18/2023] [Accepted: 12/27/2023] [Indexed: 02/03/2024] Open
Abstract
Alternative splicing (AS) serves as a pivotal mechanism in transcriptional regulation, engendering transcript diversity, and modifications in protein structure and functionality. Across varying tissues, developmental stages, or under specific conditions, AS gives rise to distinct splice isoforms. This implies that these isoforms possess unique temporal and spatial roles, thereby associating AS with standard biological activities and diseases. Among these, AS-related RNA-binding proteins (RBPs) play an instrumental role in regulating alternative splicing events. Under physiological conditions, the diversity of proteins mediated by AS influences the structure, function, interaction, and localization of proteins, thereby participating in the differentiation and development of an array of tissues and organs. Under pathological conditions, alterations in AS are linked with various diseases, particularly cancer. These changes can lead to modifications in gene splicing patterns, culminating in changes or loss of protein functionality. For instance, in cancer, abnormalities in AS and RBPs may result in aberrant expression of cancer-associated genes, thereby promoting the onset and progression of tumors. AS and RBPs are also associated with numerous neurodegenerative diseases and autoimmune diseases. Consequently, the study of AS across different tissues holds significant value. This review provides a detailed account of the recent advancements in the study of alternative splicing and AS-related RNA-binding proteins in tissue development and diseases, which aids in deepening the understanding of gene expression complexity and offers new insights and methodologies for precision medicine.
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Affiliation(s)
- Yining Tao
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Qi Zhang
- Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory for Tumor Microenvironment and Inflammation, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
| | - Haoyu Wang
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Xiyu Yang
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China
- Shanghai Bone Tumor Institution, 200000, Shanghai, China
| | - Haoran Mu
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 200000, Shanghai, China.
- Shanghai Bone Tumor Institution, 200000, Shanghai, China.
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8
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Shi Y, Ding G, Shen H, Li Z, Li H, Xiao G. Genome-wide identification and expression profiles analysis of the authentic response regulator gene family in licorice. FRONTIERS IN PLANT SCIENCE 2024; 14:1309802. [PMID: 38273943 PMCID: PMC10809405 DOI: 10.3389/fpls.2023.1309802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 12/18/2023] [Indexed: 01/27/2024]
Abstract
Introduction As one of the traditional Chinese medicinal herbs that were most generally used, licorice attracts lots of interest due to its therapeutic potential. Authentic response regulators (ARRs) are key factors in cytokinin signal transduction and crucial for plant growth and stress response processes. Nevertheless, the characteristics and functions of the licorice ARR genes are still unknown. Results In present study, a systematic genome-wide identification and expression analysis of the licorice ARR gene family were conducted and 51 ARR members were identified. Collinearity analysis revealed the significant roles of segmental duplications in the expansion of licorice ARR genes. The cis-acting elements associated with development, stress and phytohormone responses were identified, implying their pivotal roles in diverse regulatory processes. RNA-seq and qRT-PCR results suggested that A-type, but not B-type ARRs were induced by zeatin. Additionally, ARRs participated in diverse abiotic stresses and phytohormones responses. Yeast one-hybrid assay demonstrated that GuARR1, GuARR2, GuARR11, GuARR12, GuARR10-1, GuARR10-2 and GuARR14 were able to bind to the promoter of GuARR8-3, and GuARR1, GuARR12 bound to the GuARR8-1 promoter. GuARR1, GuARR2, GuARR11 and GuARR10-2 bound to the GuARR6-2 promoter as well as GuARR12 and GuARR10-2 bound to the GuARR6-1 promoter. Discussion Collectively, these findings provide a basis for future ARR genes function investigations, shedding light on the potential medicinal properties and agricultural applications of licorice.
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Affiliation(s)
- Yanping Shi
- College of Life Sciences, Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, Shihezi University, Shihezi, China
| | - Guohua Ding
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
| | - Haitao Shen
- College of Life Sciences, Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, Shihezi University, Shihezi, China
| | - Zihan Li
- Geosystems Research Institute, Mississippi State University, Starkville, MS, United States
| | - Hongbin Li
- College of Life Sciences, Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, Shihezi University, Shihezi, China
| | - Guanghui Xiao
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
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9
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Kosmara D, Papanikolaou S, Nikolaou C, Bertsias G. Extensive Alternative Splicing Patterns in Systemic Lupus Erythematosus Highlight Sexual Differences. Cells 2023; 12:2678. [PMID: 38067106 PMCID: PMC10705143 DOI: 10.3390/cells12232678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/19/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Substantial evidence highlights divergences in immune responses between men and women. Women are more susceptible to autoimmunity, whereas men suffer from the more severe presentation of autoimmune disorders. The molecular mechanism of this sexual dimorphism remains elusive. Herein, we conducted a comprehensive analysis of sex differences in whole-blood gene expression focusing on alternative splicing (AS) events in systemic lupus erythematosus (SLE), which is a prototype sex-biased disease. This study included 79 SLE patients with active disease and 58 matched healthy controls who underwent whole-blood RNA sequencing. Sex differences in splicing events were widespread, existent in both SLE and a healthy state. However, we observed distinct gene sets and molecular pathways targeted by sex-dependent AS in SLE patients as compared to healthy subjects, as well as a notable sex dissimilarity in intron retention events. Sexually differential spliced genes specific to SLE patients were enriched for dynamic cellular processes including chromatin remodeling, stress and inflammatory responses. Remarkably, the extent of sexual differences in AS in the SLE patients and healthy individuals exceeded those in gene expression. Overall, this study reveals an unprecedent variation in sex-dependent splicing events in SLE and the healthy state, with potential implications for understanding the molecular basis of sexual dimorphism in autoimmunity.
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Affiliation(s)
- Despoina Kosmara
- Rheumatology and Clinical Immunology, University Hospital of Heraklion and University of Crete Medical School, 71500 Heraklion, Greece
- Foundation for Research and Technology-Hellas (FORTH), Infections and Immunity, Institute of Molecular Biology and Biotechnology, 71110 Heraklion, Greece
| | - Sofia Papanikolaou
- Rheumatology and Clinical Immunology, University Hospital of Heraklion and University of Crete Medical School, 71500 Heraklion, Greece
- Biomedical Sciences Research Center “Alexander Fleming”, Institute of Bioinnovation, 16672 Athens, Greece
| | - Christoforos Nikolaou
- Biomedical Sciences Research Center “Alexander Fleming”, Institute of Bioinnovation, 16672 Athens, Greece
| | - George Bertsias
- Rheumatology and Clinical Immunology, University Hospital of Heraklion and University of Crete Medical School, 71500 Heraklion, Greece
- Foundation for Research and Technology-Hellas (FORTH), Infections and Immunity, Institute of Molecular Biology and Biotechnology, 71110 Heraklion, Greece
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10
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Khalifah BA, Alghamdi SA, Alhasan AH. Unleashing the potential of catalytic RNAs to combat mis-spliced transcripts. Front Bioeng Biotechnol 2023; 11:1244377. [PMID: 38047291 PMCID: PMC10690607 DOI: 10.3389/fbioe.2023.1244377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 10/23/2023] [Indexed: 12/05/2023] Open
Abstract
Human transcriptome can undergo RNA mis-splicing due to spliceopathies contributing to the increasing number of genetic diseases including muscular dystrophy (MD), Alzheimer disease (AD), Huntington disease (HD), myelodysplastic syndromes (MDS). Intron retention (IR) is a major inducer of spliceopathies where two or more introns remain in the final mature mRNA and account for many intronic expansion diseases. Potential removal of such introns for therapeutic purposes can be feasible when utilizing bioinformatics, catalytic RNAs, and nano-drug delivery systems. Overcoming delivery challenges of catalytic RNAs was discussed in this review as a future perspective highlighting the significance of utilizing synthetic biology in addition to high throughput deep sequencing and computational approaches for the treatment of mis-spliced transcripts.
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Affiliation(s)
- Bashayer A. Khalifah
- Institute for Bioengineering, Health Sector, King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia
- Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Ali H. Alhasan
- Institute for Bioengineering, Health Sector, King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia
- College of Science and General Studies, Alfaisal University, Riyadh, Saudi Arabia
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11
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Werren E, LaForce G, Srivastava A, Perillo D, Johnson K, Berger B, Regan S, Pfennig C, Baris S, de Munnik S, Pfundt R, Hebbar M, Jimenez Heredia R, Karakoc-Aydiner E, Ozen A, Dmytrus J, Krolo A, Corning K, Prijoles E, Louie R, Lebel R, Le TL, Amiel J, Gordon C, Boztug K, Girisha K, Shukla A, Bielas S, Schaffer A. Mechanisms of mRNA processing defects in inherited THOC6 intellectual disability syndrome. RESEARCH SQUARE 2023:rs.3.rs-2126145. [PMID: 37720017 PMCID: PMC10503840 DOI: 10.21203/rs.3.rs-2126145/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
THOC6 is the genetic basis of autosomal recessive THOC6 Intellectual Disability Syndrome (TIDS). THOC6 facilitates the formation of the Transcription Export complex (TREX) tetramer, composed of four THO monomers. The TREX tetramer supports mammalian mRNA processing that is distinct from yeast TREX dimer functions. Human and mouse TIDS model systems allow novel THOC6-dependent TREX tetramer functions to be investigated. Biallelic loss-of-functon(LOF) THOC6 variants do not influence the expression and localization of TREX members in human cells, but our data suggests reduced binding affinity of ALYREF. Impairment of TREX nuclear export functions were not detected in cells with biallelic THOC6 LOF. Instead, mRNA mis-splicing was observed in human and mouse neural tissue, revealing novel insights into THOC6-mediated TREX coordination of mRNA processing. We demonstrate that THOC6 is required for regulation of key signaling pathways in human corticogenesis that dictate the transition from proliferative to neurogenic divisions that may inform TIDS neuropathology.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Jasmin Dmytrus
- CeMM Research Centre for Molecular Medicine of the Austrian Academy of Sciences
| | - Ana Krolo
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases
| | | | | | | | | | - Thuy-Linh Le
- Imagine Institute, INSERM U1163, Paris Descartes University
| | | | - Christopher Gordon
- Institut National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine
| | - Kaan Boztug
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases
| | - Katta Girisha
- Kasturba Medical College, Manipal, Manipal Academy of Higher Education
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12
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Xiao W, Yeom KH, Lin CH, Black DL. Improved enzymatic labeling of fluorescent in situ hybridization probes applied to the visualization of retained introns in cells. RNA (NEW YORK, N.Y.) 2023; 29:1274-1287. [PMID: 37130703 PMCID: PMC10351894 DOI: 10.1261/rna.079591.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/31/2023] [Indexed: 05/04/2023]
Abstract
Fluorescence in situ hybridization (FISH) is a widely used tool for quantifying gene expression and determining the location of RNA molecules in cells. We present an improved method for FISH probe production that yields high-purity probes with a wide range of fluorophores using standard laboratory equipment at low cost. The method modifies an earlier protocol that uses terminal deoxynucleotidyl transferase to add fluorescently labeled nucleotides to synthetic deoxyoligonucleotides. In our protocol, amino-11-ddUTP is joined to an oligonucleotide pool prior to its conjugation to a fluorescent dye, thereby generating pools of probes ready for a variety of modifications. This order of reaction steps allows for high labeling efficiencies regardless of the GC content or terminal base of the oligonucleotides. The degree of labeling (DOL) for spectrally distinct fluorophores (Quasar, ATTO, and Alexa dyes) was mostly >90%, comparable with commercial probes. The ease and low cost of production allowed the generation of probe sets targeting a wide variety of RNA molecules. Using these probes, FISH assays in C2C12 cells showed the expected subcellular localization of mRNAs and pre-mRNAs for Polr2a (RNA polymerase II subunit 2a) and Gapdh, and of the long noncoding RNAs Malat1 and Neat1 Developing FISH probe sets for several transcripts containing retained introns, we found that retained introns in the Gabbr1 and Noc2l transcripts are present in subnuclear foci separate from their sites of synthesis and partially coincident with nuclear speckles. This labeling protocol should have many applications in RNA biology.
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Affiliation(s)
- Wen Xiao
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Kyu-Hyeon Yeom
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Chia-Ho Lin
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - Douglas L Black
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
- Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
- Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095, USA
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13
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Sun X, Liu Z, Li Z, Zeng Z, Peng W, Zhu J, Zhao J, Zhu C, Zeng C, Stearrett N, Crandall KA, Bachali P, Grammer AC, Lipsky PE. Abnormalities in intron retention characterize patients with systemic lupus erythematosus. Sci Rep 2023; 13:5141. [PMID: 36991079 PMCID: PMC10060252 DOI: 10.1038/s41598-023-31890-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 03/20/2023] [Indexed: 03/31/2023] Open
Abstract
Regulation of intron retention (IR), a form of alternative splicing, is a newly recognized checkpoint in gene expression. Since there are numerous abnormalities in gene expression in the prototypic autoimmune disease systemic lupus erythematosus (SLE), we sought to determine whether IR was intact in patients with this disease. We, therefore, studied global gene expression and IR patterns of lymphocytes in SLE patients. We analyzed RNA-seq data from peripheral blood T cell samples from 14 patients suffering from systemic lupus erythematosus (SLE) and 4 healthy controls and a second, independent data set of RNA-seq data from B cells from16 SLE patients and 4 healthy controls. We identified intron retention levels from 26,372 well annotated genes as well as differential gene expression and tested for differences between cases and controls using unbiased hierarchical clustering and principal component analysis. We followed with gene-disease enrichment analysis and gene-ontology enrichment analysis. Finally, we then tested for significant differences in intron retention between cases and controls both globally and with respect to specific genes. Overall decreased IR was found in T cells from one cohort and B cells from another cohort of patients with SLE and was associated with increased expression of numerous genes, including those encoding spliceosome components. Different introns within the same gene displayed both up- and down-regulated retention profiles indicating a complex regulatory mechanism. These results indicate that decreased IR in immune cells is characteristic of patients with active SLE and may contribute to the abnormal expression of specific genes in this autoimmune disease.
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Affiliation(s)
- Xiaoqian Sun
- Computer Science Department, George Washington University, Washington, DC, 20052, USA
| | - Zhichao Liu
- Physics Department, George Washington University, Washington, DC, 20052, USA
| | - Zongzhu Li
- Physics Department, George Washington University, Washington, DC, 20052, USA
| | - Zhouhao Zeng
- Physics Department, George Washington University, Washington, DC, 20052, USA
| | - Weiqun Peng
- Physics Department, George Washington University, Washington, DC, 20052, USA
| | - Jun Zhu
- Mokobio Biotechnology R&D Center, 1445 Research Blvd, Suite 150, Rockville, MD, 20850, USA
| | - Joel Zhao
- Walt Whitman High School, Bethesda, MD, 20817, USA
| | | | - Chen Zeng
- Physics Department, George Washington University, Washington, DC, 20052, USA.
| | - Nathaniel Stearrett
- Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, DC, 20052, USA
| | - Keith A Crandall
- Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, DC, 20052, USA.
| | - Prathyusha Bachali
- RILITE Research Institute and AMPEL BioSolutions, 250 W Main St, Ste 300, Charlottesville, VA, 22902, USA
| | - Amrie C Grammer
- RILITE Research Institute and AMPEL BioSolutions, 250 W Main St, Ste 300, Charlottesville, VA, 22902, USA
| | - Peter E Lipsky
- RILITE Research Institute and AMPEL BioSolutions, 250 W Main St, Ste 300, Charlottesville, VA, 22902, USA.
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14
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Ullah F, Jabeen S, Salton M, Reddy ASN, Ben-Hur A. Evidence for the role of transcription factors in the co-transcriptional regulation of intron retention. Genome Biol 2023; 24:53. [PMID: 36949544 PMCID: PMC10031921 DOI: 10.1186/s13059-023-02885-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/16/2023] [Indexed: 03/24/2023] Open
Abstract
BACKGROUND Alternative splicing is a widespread regulatory phenomenon that enables a single gene to produce multiple transcripts. Among the different types of alternative splicing, intron retention is one of the least explored despite its high prevalence in both plants and animals. The recent discovery that the majority of splicing is co-transcriptional has led to the finding that chromatin state affects alternative splicing. Therefore, it is plausible that transcription factors can regulate splicing outcomes. RESULTS We provide evidence for the hypothesis that transcription factors are involved in the regulation of intron retention by studying regions of open chromatin in retained and excised introns. Using deep learning models designed to distinguish between regions of open chromatin in retained introns and non-retained introns, we identified motifs enriched in IR events with significant hits to known human transcription factors. Our model predicts that the majority of transcription factors that affect intron retention come from the zinc finger family. We demonstrate the validity of these predictions using ChIP-seq data for multiple zinc finger transcription factors and find strong over-representation for their peaks in intron retention events. CONCLUSIONS This work opens up opportunities for further studies that elucidate the mechanisms by which transcription factors affect intron retention and other forms of splicing. AVAILABILITY Source code available at https://github.com/fahadahaf/chromir.
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Affiliation(s)
- Fahad Ullah
- Department of Computer Science, Colorado State University, Fort Collins, CO, USA
| | - Saira Jabeen
- Department of Computer Science, Colorado State University, Fort Collins, CO, USA
| | - Maayan Salton
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Anireddy S N Reddy
- Biochemistry and Molecular Biology Department, The Hebrew University Faculty of Medicine, Jerusalem, Israel
| | - Asa Ben-Hur
- Department of Computer Science, Colorado State University, Fort Collins, CO, USA.
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15
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Li J, Gao X, Chen X, Fan Z, Zhang Y, Wang Z, Shi J, Wang C, Zhang H, Wang L, Zhao Q. Comparative transcriptome responses of leaf and root tissues to salt stress in wheat strains with different salinity tolerances. Front Genet 2023; 14:1015599. [PMID: 36911411 PMCID: PMC9996022 DOI: 10.3389/fgene.2023.1015599] [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: 08/09/2022] [Accepted: 02/07/2023] [Indexed: 02/25/2023] Open
Abstract
Background: Salinity stress is a major adverse environmental factor that can limit crop yield and restrict normal land use. The selection of salt-tolerant strains and elucidation of the underlying mechanisms by plant breeding scientists are urgently needed to increase agricultural production in arid and semi-arid regions. Results: In this study, we selected the salt-tolerant wheat (Triticum aestivum) strain ST9644 as a model to study differences in expression patterns between salt-tolerant and salt-sensitive strains. High-throughput RNA sequencing resulted in more than 359.10 Gb of clean data from 54 samples, with an average of 6.65 Gb per sample. Compared to the IWGSC reference annotation, we identified 50,096 new genes, 32,923 of which have functional annotations. Comparisons of abundances between salt-tolerant and salt-sensitive strains revealed 3,755, 5,504, and 4,344 genes that were differentially expressed at 0, 6, and 24 h, respectively, in root tissue under salt stress. KEGG pathway analysis of these genes showed that they were enriched for phenylpropanoid biosynthesis (ko00940), cysteine and methionine metabolism (ko00270), and glutathione metabolism (ko00480). We also applied weighted gene co-expression network analysis (WGCNA) analysis to determine the time course of root tissue response to salt stress and found that the acute response lasts >6 h and ends before 12 h. We also identified key alternative splicing factors showing different splicing patterns in salt-sensitive and salt-tolerant strains; however, only few of them were differentially expressed in the two groups. Conclusion: Our results offer a better understanding of wheat salt tolerance and improve wheat breeding.
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Affiliation(s)
- Jianfeng Li
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Xin Gao
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Xunji Chen
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Zheru Fan
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Yueqiang Zhang
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Zhong Wang
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Jia Shi
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Chunsheng Wang
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Hongzhi Zhang
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Lihong Wang
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
| | - Qi Zhao
- Institute of Nuclear and Biological Technologies, Xinjiang Academy of Agricultural Sciences, Urummqi, China
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16
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David JK, Maden SK, Wood MA, Thompson RF, Nellore A. Retained introns in long RNA-seq reads are not reliably detected in sample-matched short reads. Genome Biol 2022; 23:240. [PMID: 36369064 PMCID: PMC9652823 DOI: 10.1186/s13059-022-02789-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 10/10/2022] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND There is growing interest in retained introns in a variety of disease contexts including cancer and aging. Many software tools have been developed to detect retained introns from short RNA-seq reads, but reliable detection is complicated by overlapping genes and transcripts as well as the presence of unprocessed or partially processed RNAs. RESULTS We compared introns detected by 8 tools using short RNA-seq reads with introns observed in long RNA-seq reads from the same biological specimens. We found significant disagreement among tools (Fleiss' [Formula: see text]) such that 47.7% of all detected intron retentions were not called by more than one tool. We also observed poor performance of all tools, with none achieving an F1-score greater than 0.26, and qualitatively different behaviors between general-purpose alternative splicing detection tools and tools confined to retained intron detection. CONCLUSIONS Short-read tools detect intron retention with poor recall and precision, calling into question the completeness and validity of a large percentage of putatively retained introns called by commonly used methods.
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Affiliation(s)
- Julianne K. David
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,Present Address: Base5 Genomics, Inc., Mountain View, CA USA
| | - Sean K. Maden
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.21107.350000 0001 2171 9311Present Address: Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| | - Mary A. Wood
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.429936.30000 0004 5914 210XPortland VA Research Foundation, Portland, OR USA ,Present Address: Phase Genomics, Inc., Seattle, WA USA
| | - Reid F. Thompson
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.484322.bDivision of Hospital and Specialty Medicine, VA Portland Healthcare System, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Radiation Medicine, Oregon Health & Science University, Portland, OR USA
| | - Abhinav Nellore
- grid.5288.70000 0000 9758 5690Computational Biology Program, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR USA ,grid.5288.70000 0000 9758 5690Department of Surgery, Oregon Health & Science University, Portland, OR USA
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17
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Hadar S, Meller A, Saida N, Shalgi R. Stress-induced transcriptional readthrough into neighboring genes is linked to intron retention. iScience 2022; 25:105543. [PMID: 36505935 PMCID: PMC9732411 DOI: 10.1016/j.isci.2022.105543] [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: 03/16/2022] [Revised: 07/10/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
Exposure to certain stresses leads to readthrough transcription. Using polyA-selected RNA-seq in mouse fibroblasts subjected to heat shock, oxidative, or osmotic stress, we found that readthrough transcription can proceed into proximal downstream genes, in a phenomenon previously termed "read-in." We found that read-in genes share distinctive genomic characteristics; they are GC-rich and extremely short , with genomic features conserved in human. Using ribosome profiling, we found that read-in genes show significantly reduced translation. Strikingly, read-in genes demonstrate marked intron retention, mostly in their first introns, which could not be explained solely by their short introns and GC-richness, features often associated with intron retention. Finally, we revealed H3K36me3 enrichment upstream to read-in genes. Moreover, demarcation of exon-intron junctions by H3K36me3 was absent in read-in first introns. Our data portray a relationship between read-in and intron retention, suggesting they may have co-evolved to facilitate reduced translation of read-in genes during stress.
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Affiliation(s)
- Shani Hadar
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa 31096, Israel
| | - Anatoly Meller
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa 31096, Israel
| | - Naseeb Saida
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa 31096, Israel
| | - Reut Shalgi
- Department of Biochemistry, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa 31096, Israel,Corresponding author
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18
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Transcriptomic complexity of the human malaria parasite Plasmodium falciparum revealed by long-read sequencing. PLoS One 2022; 17:e0276956. [PMID: 36331983 PMCID: PMC9635732 DOI: 10.1371/journal.pone.0276956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022] Open
Abstract
The Plasmodium falciparum human malaria parasite genome is incompletely annotated and does not accurately represent the transcriptomic diversity of this species. To address this need, we performed long-read transcriptomic sequencing. 5' capped mRNA was enriched from samples of total and nuclear-fractionated RNA from intra-erythrocytic stages and converted to cDNA library. The cDNA libraries were sequenced on PacBio and Nanopore long-read platforms. 12,495 novel isoforms were annotated from the data. Alternative 5' and 3' ends represent the majority of isoform events among the novel isoforms, with retained introns being the next most common event. The majority of alternative 5' ends correspond to genomic regions with features similar to those of the reference transcript 5' ends. However, a minority of alternative 5' ends showed markedly different features, including locations within protein-coding regions. Alternative 3' ends showed similar features to the reference transcript 3' ends, notably adenine-rich termination signals. Distinguishing features of retained introns could not be observed, except for a tendency towards shorter length and greater GC content compared with spliced introns. Expression of antisense and retained intron isoforms was detected at different intra-erythrocytic stages, suggesting developmental regulation of these isoform events. To gain insights into the possible functions of the novel isoforms, their protein-coding potential was assessed. Variants of P. falciparum proteins and novel proteins encoded by alternative open reading frames suggest that P. falciparum has a greater proteomic repertoire than the current annotation. We provide a catalog of annotated transcripts and encoded alternative proteins to support further studies on gene and protein regulation of this pathogen.
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19
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Roces V, Lamelas L, Valledor L, Carbó M, Cañal MJ, Meijón M. Integrative analysis in Pinus revealed long-term heat stress splicing memory. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:998-1013. [PMID: 36151923 PMCID: PMC9828640 DOI: 10.1111/tpj.15990] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 08/31/2022] [Accepted: 09/15/2022] [Indexed: 05/09/2023]
Abstract
Due to the current climate change, many studies have described main drivers in abiotic stress. Recent findings suggest that alternative splicing (AS) has a critical role in controlling plant responses to high temperature. AS is a mechanism that allows organisms to create an assortment of RNA transcripts and proteins using a single gene. However, the most important roles of AS in stress could not be rigorously addressed because research has been focused on model species, covering only a narrow phylogenetic and lifecycle spectrum. Thus, AS degree of diversification among more dissimilar taxa in heat response is still largely unknown. To fill this gap, the present study employs a systems biology approach to examine how the AS landscape responds to and 'remembers' heat stress in conifers, a group which has received little attention even though their position can solve key evolutionary questions. Contrary to angiosperms, we found that potential intron retention may not be the most prevalent type of AS. Furthermore, our integrative analysis with metabolome and proteome data places splicing as the main source of variation during the response. Finally, we evaluated possible acquired long-term splicing memory in a diverse subset of events, and although this mechanism seems to be conserved in seed plants, AS dynamics are divergent. These discoveries reveal the particular way of remembering past temperature changes in long-lived plants and open the door to include species with unique features to determine the extent of conservation in gene expression regulation.
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Affiliation(s)
- Víctor Roces
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
| | - Laura Lamelas
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
| | - Luis Valledor
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
| | - María Carbó
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
| | - María Jesús Cañal
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
| | - Mónica Meijón
- Plant Physiology, Department of Organisms and Systems Biology, Faculty of Biology and Biotechnology Institute of AsturiasUniversity of OviedoOviedoAsturiasSpain
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Petrić Howe M, Crerar H, Neeves J, Harley J, Tyzack GE, Klein P, Ramos A, Patani R, Luisier R. Physiological intron retaining transcripts in the cytoplasm abound during human motor neurogenesis. Genome Res 2022; 32:1808-1825. [PMID: 36180233 PMCID: PMC9712626 DOI: 10.1101/gr.276898.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/16/2022] [Indexed: 11/24/2022]
Abstract
Intron retention (IR) is now recognized as a dominant splicing event during motor neuron (MN) development; however, the role and regulation of intron-retaining transcripts (IRTs) localized to the cytoplasm remain particularly understudied. Here we show that IR is a physiological process that is spatiotemporally regulated during MN lineage restriction and that IRTs in the cytoplasm are detected in as many as 13% (n = 2297) of the genes expressed during this process. We identify a major class of cytoplasmic IRTs that are not associated with reduced expression of their own genes but instead show a high capacity for RNA-binding protein and miRNA occupancy. Finally, we show that ALS-causing VCP mutations lead to a selective increase in cytoplasmic abundance of this particular class of IRTs, which in turn temporally coincides with an increase in the nuclear expression level of predicted miRNA target genes. Altogether, our study identifies a previously unrecognized class of cytoplasmic intronic sequences with potential regulatory function beyond gene expression.
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Affiliation(s)
- Marija Petrić Howe
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Hamish Crerar
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Jacob Neeves
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Jasmine Harley
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Giulia E Tyzack
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Pierre Klein
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Research Department of Structural and Molecular Biology, University College London, London WC1E 6XA, United Kingdom
| | - Andres Ramos
- Research Department of Structural and Molecular Biology, University College London, London WC1E 6XA, United Kingdom
| | - Rickie Patani
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Raphaëlle Luisier
- Idiap Research Institute, Genomics and Health Informatics, CH-1920 Martigny, Switzerland
- SIB Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
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Dynamic Transcriptional Landscape of Grass Carp (Ctenopharyngodon idella) Reveals Key Transcriptional Features Involved in Fish Development. Int J Mol Sci 2022; 23:ijms231911547. [PMID: 36232849 PMCID: PMC9569805 DOI: 10.3390/ijms231911547] [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: 08/31/2022] [Revised: 09/23/2022] [Accepted: 09/23/2022] [Indexed: 11/17/2022] Open
Abstract
A high-quality baseline transcriptome is a valuable resource for developmental research as well as a useful reference for other studies. We gathered 41 samples representing 11 tissues/organs from 22 important developmental time points within 197 days of fertilization of grass carp eggs in order to systematically examine the role of lncRNAs and alternative splicing in fish development. We created a high-quality grass carp baseline transcriptome with a completeness of up to 93.98 percent by combining strand-specific RNA sequencing and single-molecule real-time RNA sequencing technologies, and we obtained temporal expression profiles of 33,055 genes and 77,582 transcripts during development and tissue differentiation. A family of short interspersed elements was preferentially expressed at the early stage of zygotic activation in grass carp, and its possible regulatory components were discovered through analysis. Additionally, after thoroughly analyzing alternative splicing events, we discovered that retained intron (RI) alternative splicing events change significantly in both zygotic activation and tissue differentiation. During zygotic activation, we also revealed the precise regulatory characteristics of the underlying functional RI events.
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Marshall JNG, Fröhlich A, Li L, Pfaff AL, Middlehurst B, Spargo TP, Iacoangeli A, Lang B, Al-Chalabi A, Koks S, Bubb VJ, Quinn JP. A polymorphic transcriptional regulatory domain in the amyotrophic lateral sclerosis risk gene CFAP410 correlates with differential isoform expression. Front Mol Neurosci 2022; 15:954928. [PMID: 36131690 PMCID: PMC9484465 DOI: 10.3389/fnmol.2022.954928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/22/2022] [Indexed: 11/15/2022] Open
Abstract
We describe the characterisation of a variable number tandem repeat (VNTR) domain within intron 1 of the amyotrophic lateral sclerosis (ALS) risk gene CFAP410 (Cilia and flagella associated protein 410) (previously known as C21orf2), providing insight into how this domain could support differential gene expression and thus be a modulator of ALS progression or risk. We demonstrated the VNTR was functional in a reporter gene assay in the HEK293 cell line, exhibiting both the properties of an activator domain and a transcriptional start site, and that the differential expression was directed by distinct repeat number in the VNTR. These properties embedded in the VNTR demonstrated the potential for this VNTR to modulate CFAP410 expression. We extrapolated these findings in silico by utilisation of tagging SNPs for the two most common VNTR alleles to establish a correlation with endogenous gene expression. Consistent with in vitro data, CFAP410 isoform expression was found to be variable in the brain. Furthermore, although the number of matched controls was low, there was evidence for one specific isoform being correlated with lower expression in those with ALS. To address if the genotype of the VNTR was associated with ALS risk, we characterised the variation of the CFAP410 VNTR in ALS cases and matched controls by PCR analysis of the VNTR length, defining eight alleles of the VNTR. No significant difference was observed between cases and controls, we noted, however, the cohort was unlikely to contain sufficient power to enable any firm conclusion to be drawn from this analysis. This data demonstrated that the VNTR domain has the potential to modulate CFAP410 expression as a regulatory element that could play a role in its tissue-specific and stimulus-inducible regulation that could impact the mechanism by which CFAP410 is involved in ALS.
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Affiliation(s)
- Jack N. G. Marshall
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Alexander Fröhlich
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Li Li
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- Department of Psychiatry, National Clinical Research Centre for Mental Disorders, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Abigail L. Pfaff
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia
| | - Ben Middlehurst
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Thomas P. Spargo
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- NIHR Biomedical Research Centre, South London and Maudsley NHS Foundation Trust, King's College London, London, United Kingdom
| | - Alfredo Iacoangeli
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- NIHR Biomedical Research Centre, South London and Maudsley NHS Foundation Trust, King's College London, London, United Kingdom
| | - Bing Lang
- Department of Psychiatry, National Clinical Research Centre for Mental Disorders, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Ammar Al-Chalabi
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- Department of Neurology, King's College Hospital, London, United Kingdom
| | - Sulev Koks
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
- Perron Institute for Neurological and Translational Science, Perth, WA, Australia
| | - Vivien J. Bubb
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - John P. Quinn
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
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de Obeso Fernández Del Valle A, Gómez-Montalvo J, Maciver SK. Acanthamoeba castellanii exhibits intron retention during encystment. Parasitol Res 2022; 121:2615-2622. [PMID: 35776211 DOI: 10.1007/s00436-022-07578-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/14/2022] [Indexed: 11/24/2022]
Abstract
Intron retention (IR) refers to the mechanism of alternative splicing in which an intron is not excised from the mature transcript. IR in the cosmopolitan free-living amoeba Acanthamoeba castellanii has not been studied. We performed an analysis of RNA sequencing data during encystment to identify genes that presented differentially retained introns during this process. We show that IR increases during cyst formation, indicating a potential mechanism of gene regulation that could help downregulate metabolism. We identify 69 introns from 67 genes that are differentially retained comparing the trophozoite stage and encystment after 24 and 48 h. These genes include several hypothetical proteins. We show different patterns of IR during encystment taking as examples a lipase, a peroxin-3 protein, an Fbox domain containing protein, a proteasome subunit, a polynucleotide adenylyltransferase, and a tetratricopeptide domain containing protein. A better understanding of IR in Acanthamoeba, and even other protists, could help elucidate changes in life cycle and combat disease such as Acanthamoeba keratitis in which the cyst is key for its persistence.
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Affiliation(s)
- Alvaro de Obeso Fernández Del Valle
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, 64849, Monterrey, Mexico.
| | - Jesús Gómez-Montalvo
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, 64849, Monterrey, Mexico
| | - Sutherland K Maciver
- Centre for Discovery Brain Sciences, Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, Scotland, UK
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Genome-Wide Analysis of the Type-B Authentic Response Regulator Gene Family in Brassica napus. Genes (Basel) 2022; 13:genes13081449. [PMID: 36011360 PMCID: PMC9408017 DOI: 10.3390/genes13081449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/07/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
The type-B authentic response regulators (type-B ARRs) are positive regulators of cytokinin signaling and involved in plant growth and stress responses. In this study, we used bioinformatics, RNA-seq, and qPCR to study the phylogenetic and expression pattern of 35 type-B ARRs in Brassica napus. The BnARRs experienced gene expansion and loss during genome polyploidization and were classified into seven groups. Whole-genome duplication (WGD) and segmental duplication were the main forces driving type-B ARR expansion in B. napus. Several BnARRs with specific expression patterns during rapeseed development were identified, including BnARR12/14/18/23/33. Moreover, we found the type-B BnARRs were involved in rapeseed development and stress responses, through participating in cytokinin and ABA signaling pathways. This study revealed the origin, evolutionary history, and expression pattern of type-B ARRs in B. napus and will be helpful to the functional characterization of BnARRs.
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Elton TS, Hernandez VA, Carvajal-Moreno J, Wang X, Ipinmoroti D, Yalowich JC. Intronic Polyadenylation in Acquired Cancer Drug Resistance Circumvented by Utilizing CRISPR/Cas9 with Homology-Directed Repair: The Tale of Human DNA Topoisomerase IIα. Cancers (Basel) 2022; 14:cancers14133148. [PMID: 35804920 PMCID: PMC9265003 DOI: 10.3390/cancers14133148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 12/02/2022] Open
Abstract
Simple Summary DNA topoisomerase IIα (170 kDa, TOP2α/170) resolves nucleic acid topological entanglements by generating transient double-strand DNA breaks. TOP2α inhibitors/poisons stabilize TOP2α-DNA covalent complexes resulting in persistent DNA damage and are frequently utilized to treat a variety of cancers. Acquired resistance to these chemotherapeutic agents is often associated with decreased TOP2α/170 expression levels. Studies have demonstrated that a reduction in TOP2α/170 results from a type of alternative polyadenylation designated intronic polyadenylation (IPA). As a consequence of IPA, variant TOP2α mRNA transcripts have been characterized that have resulted in the translation of C-terminal truncated TOP2α isoforms with altered biological activities. In this paper, an example is discussed where circumvention of acquired TOP2α-mediated drug resistance was achieved by utilizing CRISPR/Cas9 specific gene editing of an exon/intron boundary through homology directed repair (HDR) to reduce TOP2α IPA. These results illustrate the therapeutic potential of CRISPR/Cas9/HDR to impact drug resistance associated with aberrant IPA. Abstract Intronic polyadenylation (IPA) plays a critical role in malignant transformation, development, progression, and cancer chemoresistance by contributing to transcriptome/proteome alterations. DNA topoisomerase IIα (170 kDa, TOP2α/170) is an established clinical target for anticancer agents whose efficacy is compromised by drug resistance often associated with a reduction of nuclear TOP2α/170 levels. In leukemia cell lines with acquired resistance to TOP2α-targeted drugs and reduced TOP2α/170 expression, variant TOP2α mRNA transcripts have been reported due to IPA that resulted in the translation of C-terminal truncated isoforms with altered nuclear-cytoplasmic distribution or heterodimerization with wild-type TOP2α/170. This review provides an overview of the various mechanisms regulating pre-mRNA processing and alternative polyadenylation, as well as the utilization of CRISPR/Cas9 specific gene editing through homology directed repair (HDR) to decrease IPA when splice sites are intrinsically weak or potentially mutated. The specific case of TOP2α exon 19/intron 19 splice site editing is discussed in etoposide-resistant human leukemia K562 cells as a tractable strategy to circumvent acquired TOP2α-mediated drug resistance. This example supports the importance of aberrant IPA in acquired drug resistance to TOP2α-targeted drugs. In addition, these results demonstrate the therapeutic potential of CRISPR/Cas9/HDR to impact drug resistance associated with aberrant splicing/polyadenylation.
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Meta-Analysis Suggests That Intron Retention Can Affect Quantification of Transposable Elements from RNA-Seq Data. BIOLOGY 2022; 11:biology11060826. [PMID: 35741347 PMCID: PMC9220773 DOI: 10.3390/biology11060826] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 02/08/2023]
Abstract
Simple Summary Transposable elements (TEs) are repetitive sequences comprising more than one third of the human genome with the original ability to change their location within the genome. Owing to their repetitive nature, the quantification of TEs results often challenging. RNA-seq is a useful tool for genome-wide TEs quantification, nevertheless it also presents technical issues, including low reads mappability and erroneous quantification derived from the transcription of TEs fragments embedded in canonical transcripts. Fragments derived from TEs are found within the introns of most genes, which led to the hypothesis that intron retention (IR) can affect the unbiased quantification of TEs expression. Performing meta-analysis of public RNA-seq datasets, here we observe that IR can indeed impact the quantification of TEs by increasing the number of reads mapped on intronic TE copies. Our work highlights a correlation between IR and TEs expression measurement by RNA-seq that should be taken into account to achieve reliable TEs quantification, especially in samples characterized by extensive IR, because differential IR might be confused with differential TEs expression. Abstract Transposable elements (TEs), also known as “jumping genes”, are repetitive sequences with the capability of changing their location within the genome. They are key players in many different biological processes in health and disease. Therefore, a reliable quantification of their expression as transcriptional units is crucial to distinguish between their independent expression and the transcription of their sequences as part of canonical transcripts. TEs quantification faces difficulties of different types, the most important one being low reads mappability due to their repetitive nature preventing an unambiguous mapping of reads originating from their sequences. A large fraction of TEs fragments localizes within introns, which led to the hypothesis that intron retention (IR) can be an additional source of bias, potentially affecting accurate TEs quantification. IR occurs when introns, normally removed from the mature transcript by the splicing machinery, are maintained in mature transcripts. IR is a widespread mechanism affecting many different genes with cell type-specific patterns. We hypothesized that, in an RNA-seq experiment, reads derived from retained introns can introduce a bias in the detection of overlapping, independent TEs RNA expression. In this study we performed meta-analysis using public RNA-seq data from lymphoblastoid cell lines and show that IR can impact TEs quantification using established tools with default parameters. Reads mapped on intronic TEs were indeed associated to the expression of TEs and influence their correct quantification as independent transcriptional units. We confirmed these results using additional independent datasets, demonstrating that this bias does not appear in samples where IR is not present and that differential TEs expression does not impact on IR quantification. We concluded that IR causes the over-quantification of intronic TEs and differential IR might be confused with differential TEs expression. Our results should be taken into account for a correct quantification of TEs expression from RNA-seq data, especially in samples in which IR is abundant.
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Bogias KJ, Pederson SM, Leemaqz S, Smith MD, McAninch D, Jankovic-Karasoulos T, McCullough D, Wan Q, Bianco-Miotto T, Breen J, Roberts CT. Placental Transcription Profiling in 6-23 Weeks' Gestation Reveals Differential Transcript Usage in Early Development. Int J Mol Sci 2022; 23:ijms23094506. [PMID: 35562897 PMCID: PMC9105363 DOI: 10.3390/ijms23094506] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/13/2022] Open
Abstract
The human placenta is a rapidly developing transient organ that is key to pregnancy success. Early development of the conceptus occurs in a low oxygen environment before oxygenated maternal blood begins to flow into the placenta at ~10-12 weeks' gestation. This process is likely to substantially affect overall placental gene expression. Transcript variability underlying gene expression has yet to be profiled. In this study, accurate transcript expression profiles were identified for 84 human placental chorionic villus tissue samples collected across 6-23 weeks' gestation. Differential gene expression (DGE), differential transcript expression (DTE) and differential transcript usage (DTU) between 6-10 weeks' and 11-23 weeks' gestation groups were assessed. In total, 229 genes had significant DTE yet no significant DGE. Integration of DGE and DTE analyses found that differential expression patterns of individual transcripts were commonly masked upon aggregation to the gene-level. Of the 611 genes that exhibited DTU, 534 had no significant DGE or DTE. The four most significant DTU genes ADAM10, VMP1, GPR126, and ASAH1, were associated with hypoxia-responsive pathways. Transcript usage is a likely regulatory mechanism in early placentation. Identification of functional roles will facilitate new insight in understanding the origins of pregnancy complications.
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Affiliation(s)
- Konstantinos J. Bogias
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
| | - Stephen M. Pederson
- Dame Roma Mitchell Cancer Research Laboratories, Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia;
| | - Shalem Leemaqz
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Melanie D. Smith
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Dale McAninch
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
| | - Tanja Jankovic-Karasoulos
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Dylan McCullough
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Qianhui Wan
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
| | - Tina Bianco-Miotto
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA 5005, Australia
| | - James Breen
- Indigenous Genomics, Telethon Kids Institute (Adelaide Office), Adelaide, SA 5000, Australia;
- College of Health & Medicine, Australian National University, Canberra, ACT 2600, Australia
| | - Claire T. Roberts
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5005, Australia; (K.J.B.); (S.L.); (D.M.); (T.J.-K.)
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia;
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (M.D.S.); (D.M.); (Q.W.)
- Correspondence:
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Reis MC, Patrun J, Ackl N, Winter P, Scheifele M, Danek A, Nolte D. A Severe Dementia Syndrome Caused by Intron Retention and Cryptic Splice Site Activation in STUB1 and Exacerbated by TBP Repeat Expansions. Front Mol Neurosci 2022; 15:878236. [PMID: 35493319 PMCID: PMC9048483 DOI: 10.3389/fnmol.2022.878236] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/08/2022] [Indexed: 11/23/2022] Open
Abstract
Heterozygous pathogenic variants in the STIP1 homologous and U-box containing protein 1 (STUB1) gene have been identified as causes of autosomal dominant inherited spinocerebellar ataxia type 48 (SCA48). SCA48 is characterized by an ataxic movement disorder that is often, but not always, accompanied by a cognitive affective syndrome. We report a severe early onset dementia syndrome that mimics frontotemporal dementia and is caused by the intronic splice donor variant c.524+1G>A in STUB1. Impaired splicing was demonstrated by RNA analysis and in minigene assays of mutated and wild-type constructs of STUB1. The most striking consequence of this splicing impairment was retention of intron 3 in STUB1, which led to an in-frame insertion of 63 amino acids (aa) (p.Arg175_Glu176ins63) into the highly conserved coiled-coil domain of its encoded protein, C-terminus of HSP70-interacting protein (CHIP). To a lesser extent, activation of two cryptic splice sites in intron 3 was observed. The almost exclusively used one, c.524+86, was not predicted by in silico programs. Variant c.524+86 caused a frameshift (p.Arg175fs*93) that resulted in a truncated protein and presumably impairs the C-terminal U-box of CHIP, which normally functions as an E3 ubiquitin ligase. The cryptic splice site c.524+99 was rarely used and led to an in-frame insertion of 33 aa (p.Arg175_Glu176ins33) that resulted in disruption of the coiled-coil domain, as has been previously postulated for complete intron 3 retention. We additionally detected repeat expansions in the range of reduced penetrance in the TATA box-binding protein (TBP) gene by excluding other genes associated with dementia syndromes. The repeat expansion was heterozygous in one patient but compound heterozygous in the more severely affected patient. Therefore, we concluded that the observed severe dementia syndrome has a digenic background, making STUB1 and TBP important candidate genes responsible for early onset dementia syndromes.
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Affiliation(s)
- Marlen Colleen Reis
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany
| | - Julia Patrun
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany
| | - Nibal Ackl
- Psychiatrische Dienste Thurgau, Münsterlingen, Switzerland
- Neurologische Klinik und Poliklinik, Klinikum der Universität München, Munich, Germany
| | - Pia Winter
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany
| | | | - Adrian Danek
- Neurologische Klinik und Poliklinik, Klinikum der Universität München, Munich, Germany
| | - Dagmar Nolte
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany
- *Correspondence: Dagmar Nolte,
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29
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Tommasi S, Kitapci TH, Blumenfeld H, Besaratinia A. Secondhand smoke affects reproductive functions by altering the mouse testis transcriptome, and leads to select intron retention in Pde1a. ENVIRONMENT INTERNATIONAL 2022; 161:107086. [PMID: 35063792 PMCID: PMC8891074 DOI: 10.1016/j.envint.2022.107086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/20/2021] [Accepted: 01/07/2022] [Indexed: 05/13/2023]
Abstract
BACKGROUND Human exposure to secondhand smoke (SHS) is known to result in adverse effects in multiple organ systems. However, the impact of SHS on the male reproductive system, particularly on the regulation of genes and molecular pathways that govern sperm production, maturation, and functions remains largely understudied. OBJECTIVE We investigated the effects of SHS on the testis transcriptome in a validated mouse model. METHODS Adult male mice were exposed to SHS (5 h/day, 5 days/week for 4 months) as compared to controls (clean air-exposed). RNA-seq analysis was performed on the testis of SHS-exposed mice and controls. Variant discovery and plink association analyses were also conducted to detect exposure-related transcript variants in SHS-treated mice. RESULTS Exposure of mice to SHS resulted in the aberrant expression of 131 testicular genes. Whilst approximately two thirds of the differentially expressed genes were protein-coding, the remaining (30.5%) comprised noncoding elements, mostly lncRNAs (19.1%). Variant discovery analysis identified a homozygous frameshift variant that is statistically significantly associated with SHS exposure (P = 7.744e-06) and is generated by retention of a short intron within Pde1a, a key regulator of spermatogenesis. Notably, this SHS-associated intron variant harbors an evolutionarily conserved, premature termination codon (PTC) that disrupts the open reading frame of Pde1a, presumably leading to its degradation via nonsense-mediated decay. DISCUSSION SHS alters the expression of genes involved in molecular pathways that are crucial for normal testis development and function. Preferential targeting of lncRNAs in the testis of SHS-exposed mice is especially significant considering their crucial role in the spatial and temporal modulation of spermatogenesis. Equally important is our discovery of a novel homozygous frameshift variant that is exclusively and significantly associated with SHS-exposure and is likely to represent a safeguard mechanism to regulate transcription of Pde1a and preserve normal testis function during harmful exposure to environmental agents.
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Affiliation(s)
- Stella Tommasi
- Department of Population and Public Health Sciences, USC Keck School of Medicine, University of Southern California, M/C 9603, Los Angeles, CA 90033, USA.
| | - Tevfik H Kitapci
- Department of Population and Public Health Sciences, USC Keck School of Medicine, University of Southern California, M/C 9603, Los Angeles, CA 90033, USA
| | - Hannah Blumenfeld
- Department of Population and Public Health Sciences, USC Keck School of Medicine, University of Southern California, M/C 9603, Los Angeles, CA 90033, USA
| | - Ahmad Besaratinia
- Department of Population and Public Health Sciences, USC Keck School of Medicine, University of Southern California, M/C 9603, Los Angeles, CA 90033, USA
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30
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Korsching E, Matschke J, Hotfilder M. Splice variants denote differences between a cancer stem cell side population of EWSR1‑ERG‑based Ewing sarcoma cells, its main population and EWSR1‑FLI‑based cells. Int J Mol Med 2022; 49:39. [PMID: 35088879 PMCID: PMC8815407 DOI: 10.3892/ijmm.2022.5094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 12/17/2021] [Indexed: 11/06/2022] Open
Abstract
Ewing sarcoma is a challenging cancer entity, which, besides the characteristic presence of a fusion gene, is driven by multiple alternative splicing events. So far, splice variants in Ewing sarcoma cells were mainly analyzed for EWSR1‑FLI1. The present study provided a comprehensive alternative splicing study on CADO‑ES1, an Ewing model cell line for an EWSR1‑ERG fusion gene. Based on a well‑-characterized RNA‑sequencing dataset with extensive control mechanisms across all levels of analysis, the differential spliced genes in Ewing cancer stem cells were ATP13A3 and EPB41, while the main population was defined by ACADVL, NOP58 and TSPAN3. All alternatively spliced genes were further characterized by their Gene Ontology (GO) terms and by their membership in known protein complexes. These results confirm and extend previous studies towards a systematic whole‑transcriptome analysis. A highlight is the striking segregation of GO terms associated with five basic splice events. This mechanistic insight, together with a coherent integration of all observations with prior knowledge, indicates that EWSR1‑ERG is truly a close twin to EWSR1‑FLI1, but still exhibits certain individuality. Thus, the present study provided a measure of variability in Ewing sarcoma, whose understanding is essential both for clinical procedures and basic mechanistic insight.
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Affiliation(s)
- Eberhard Korsching
- Institute of Bioinformatics, Faculty of Medicine, University of Münster, D‑48149 Münster, Germany
| | - Julian Matschke
- Institute of Bioinformatics, Faculty of Medicine, University of Münster, D‑48149 Münster, Germany
| | - Marc Hotfilder
- Department of Pediatric Hematology and Oncology, University Hospital Münster, D‑48149 Münster, Germany
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31
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He B, Wei C, Cai Q, Zhang P, Shi S, Peng X, Zhao Z, Yin W, Tu G, Peng W, Tao Y, Wang X. Switched alternative splicing events as attractive features in lung squamous cell carcinoma. Cancer Cell Int 2022; 22:5. [PMID: 34986865 PMCID: PMC8734344 DOI: 10.1186/s12935-021-02429-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 12/23/2021] [Indexed: 11/10/2022] Open
Abstract
Background Alternative splicing (AS) plays important roles in transcriptome and proteome diversity. Its dysregulation has a close affiliation with oncogenic processes. This study aimed to evaluate AS-based biomarkers by machine learning algorithms for lung squamous cell carcinoma (LUSC) patients. Method The Cancer Genome Atlas (TCGA) database and TCGA SpliceSeq database were utilized. After data composition balancing, Boruta feature selection and Spearman correlation analysis were used for differentially expressed AS events. Random forests and a nested fivefold cross-validation were applied for lymph node metastasis (LNM) classifier building. Random survival forest combined with Cox regression model was performed for a prognostic model, based on which a nomogram was developed. Functional enrichment analysis and Spearman correlation analysis were also conducted to explore underlying mechanisms. The expression of some switch-involved AS events along with parent genes was verified by qRT-PCR with 20 pairs of normal and LUSC tissues. Results We found 16 pairs of splicing events from same parent genes which were strongly related to the splicing switch (intrapair correlation coefficient = − 1). Next, we built a reliable LNM classifier based on 13 AS events as well as a nice prognostic model, in which switched AS events behaved prominently. The qRT-PCR presented consistent results with previous bioinformatics analysis, and some AS events like ITIH5-10715-AT and QKI-78404-AT showed remarkable detection efficiency for LUSC. Conclusion AS events, especially switched ones from the same parent genes, could provide new insights into the molecular diagnosis and therapeutic drug design of LUSC. Supplementary Information The online version contains supplementary material available at 10.1186/s12935-021-02429-2.
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Affiliation(s)
- Boxue He
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Xiangya School of Medicine, Central South University, Changsha, 410008, China
| | - Cong Wei
- Xiangya School of Medicine, Central South University, Changsha, 410008, China
| | - Qidong Cai
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Pengfei Zhang
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Shuai Shi
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Xiong Peng
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Zhenyu Zhao
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Wei Yin
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Guangxu Tu
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Weilin Peng
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Yongguang Tao
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China.,Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Department of Pathology, Xiangya Hospital, Central South University, Hunan, 410078, China.,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China
| | - Xiang Wang
- Department of Thoracic Surgery, Second Xiangya Hospital, Central South University, Changsha, 410011, China. .,Hunan Key Laboratory of Early Diagnosis and Precise Treatment of Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China.
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32
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Scarborough AM, Govindan A, Conrad NK. Genome-Wide CRISPR Screening to Identify Mammalian Factors that Regulate Intron Retention. Methods Mol Biol 2022; 2537:263-284. [PMID: 35895270 DOI: 10.1007/978-1-0716-2521-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Intron retention (IR) regulates gene expression to control fundamental biological processes like metabolism, differentiation, and cell cycle. Despite a wide variety of genes controlled by IR, few techniques are available to identify regulators of IR in an unbiased manner. Here, we describe a CRISPR knockout screening method that can be applied to uncover regulators of IR. This method uses GFP reporter constructs containing a retained intron from a gene of interest such that GFP signal is regulated by IR in the same fashion as the endogenous gene. The GFP levels are then used as a readout for genome-wide CRISPR screening. We have successfully used this approach to identify novel regulator of IR of the MAT2A transcript and propose that similar screens will be broadly applicable for the identification of novel factors that control IR of specific transcripts.
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Affiliation(s)
- Anna M Scarborough
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Ashwin Govindan
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Nicholas K Conrad
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA.
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33
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Family-Based Whole-Exome Analysis of Specific Language Impairment (SLI) Identifies Rare Variants in BUD13, a Component of the Retention and Splicing (RES) Complex. Brain Sci 2021; 12:brainsci12010047. [PMID: 35053791 PMCID: PMC8773923 DOI: 10.3390/brainsci12010047] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/18/2021] [Accepted: 12/27/2021] [Indexed: 12/12/2022] Open
Abstract
Specific language impairment (SLI) is a common neurodevelopmental disorder (NDD) that displays high heritability estimates. Genetic studies have identified several loci, but the molecular basis of SLI remains unclear. With the aim to better understand the genetic architecture of SLI, we performed whole-exome sequencing (WES) in a single family (ID: 489; n = 11). We identified co-segregating rare variants in three new genes: BUD13, APLP2, and NDRG2. To determine the significance of these genes in SLI, we Sanger sequenced all coding regions of each gene in unrelated individuals with SLI (n = 175). We observed 13 additional rare variants in 18 unrelated individuals. Variants in BUD13 reached genome-wide significance (p-value < 0.01) upon comparison with similar variants in the 1000 Genomes Project, providing gene level evidence that BUD13 is involved in SLI. Additionally, five BUD13 variants showed cohesive variant level evidence of likely pathogenicity. Bud13 is a component of the retention and splicing (RES) complex. Additional supportive evidence from studies of an animal model (loss-of-function mutations in BUD13 caused a profound neural phenotype) and individuals with an NDD phenotype (carrying a CNV spanning BUD13), indicates BUD13 could be a target for investigation of the neural basis of language.
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34
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Kumari A, Sedehizadeh S, Brook JD, Kozlowski P, Wojciechowska M. Differential fates of introns in gene expression due to global alternative splicing. Hum Genet 2021; 141:31-47. [PMID: 34907472 PMCID: PMC8758631 DOI: 10.1007/s00439-021-02409-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 12/02/2021] [Indexed: 02/06/2023]
Abstract
The discovery of introns over four decades ago revealed a new vision of genes and their interrupted arrangement. Throughout the years, it has appeared that introns play essential roles in the regulation of gene expression. Unique processing of excised introns through the formation of lariats suggests a widespread role for these molecules in the structure and function of cells. In addition to rapid destruction, these lariats may linger on in the nucleus or may even be exported to the cytoplasm, where they remain stable circular RNAs (circRNAs). Alternative splicing (AS) is a source of diversity in mature transcripts harboring retained introns (RI-mRNAs). Such RNAs may contain one or more entire retained intron(s) (RIs), but they may also have intron fragments resulting from sequential excision of smaller subfragments via recursive splicing (RS), which is characteristic of long introns. There are many potential fates of RI-mRNAs, including their downregulation via nuclear and cytoplasmic surveillance systems and the generation of new protein isoforms with potentially different functions. Various reports have linked the presence of such unprocessed transcripts in mammals to important roles in normal development and in disease-related conditions. In certain human neurological-neuromuscular disorders, including myotonic dystrophy type 2 (DM2), frontotemporal dementia/amyotrophic lateral sclerosis (FTD/ALS) and Duchenne muscular dystrophy (DMD), peculiar processing of long introns has been identified and is associated with their pathogenic effects. In this review, we discuss different mechanisms involved in the processing of introns during AS and the functions of these large sections of the genome in our biology.
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Affiliation(s)
- Anjani Kumari
- Queen's Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Saam Sedehizadeh
- Queen's Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - John David Brook
- Queen's Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Piotr Kozlowski
- Department of Molecular Genetics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704, Poznan, Poland
| | - Marzena Wojciechowska
- Department of Molecular Genetics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704, Poznan, Poland. .,Department of Rare Human Diseases, Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704, Poznan, Poland.
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35
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Conboy JG. A Deep Exon Cryptic Splice Site Promotes Aberrant Intron Retention in a Von Willebrand Disease Patient. Int J Mol Sci 2021; 22:13248. [PMID: 34948044 PMCID: PMC8706089 DOI: 10.3390/ijms222413248] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 12/13/2022] Open
Abstract
A translationally silent single nucleotide mutation in exon 44 (E44) of the von Willebrand factor (VWF) gene is associated with inefficient removal of intron 44 in a von Willebrand disease (VWD) patient. This intron retention (IR) event was previously attributed to reordered E44 secondary structure that sequesters the normal splice donor site. We propose an alternative mechanism: the mutation introduces a cryptic splice donor site that interferes with the function of the annotated site to favor IR. We evaluated both models using minigene splicing reporters engineered to vary in secondary structure and/or cryptic splice site content. Analysis of splicing efficiency in transfected K562 cells suggested that the mutation-generated cryptic splice site in E44 was sufficient to induce substantial IR. Mutations predicted to vary secondary structure at the annotated site also had modest effects on IR and shifted the balance of residual splicing between the cryptic site and annotated site, supporting competition among the sites. Further studies demonstrated that introduction of cryptic splice donor motifs at other positions in E44 did not promote IR, indicating that interference with the annotated site is context dependent. We conclude that mutant deep exon splice sites can interfere with proper splicing by inducing IR.
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Affiliation(s)
- John G Conboy
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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36
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CYP11B1 variants influence skeletal maturation via alternative splicing. Commun Biol 2021; 4:1274. [PMID: 34754074 PMCID: PMC8578655 DOI: 10.1038/s42003-021-02774-y] [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: 06/25/2020] [Accepted: 09/24/2021] [Indexed: 12/13/2022] Open
Abstract
We performed genome-wide association study meta-analysis to identify genetic determinants of skeletal age (SA) deviating in multiple growth disorders. The joint meta-analysis (N = 4557) in two multiethnic cohorts of school-aged children identified one locus, CYP11B1 (expression confined to the adrenal gland), robustly associated with SA (rs6471570-A; β = 0.14; P = 6.2 × 10-12). rs6410 (a synonymous variant in the first exon of CYP11B1 in high LD with rs6471570), was prioritized for functional follow-up being second most significant and the one closest to the first intron-exon boundary. In 208 adrenal RNA-seq samples from GTEx, C-allele of rs6410 was associated with intron 3 retention (P = 8.11 × 10-40), exon 4 inclusion (P = 4.29 × 10-34), and decreased exon 3 and 5 splicing (P = 7.85 × 10-43), replicated using RT-PCR in 15 adrenal samples. As CYP11B1 encodes 11-β-hydroxylase, involved in adrenal glucocorticoid and mineralocorticoid biosynthesis, our findings highlight the role of adrenal steroidogenesis in SA in healthy children, suggesting alternative splicing as a likely underlying mechanism.
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37
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Manet E, Polvèche H, Mure F, Mrozek-Gorska P, Roisné-Hamelin F, Hammerschmidt W, Auboeuf D, Gruffat H. Modulation of alternative splicing during early infection of human primary B lymphocytes with Epstein-Barr virus (EBV): a novel function for the viral EBNA-LP protein. Nucleic Acids Res 2021; 49:10657-10676. [PMID: 34530456 PMCID: PMC8501971 DOI: 10.1093/nar/gkab787] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 08/27/2021] [Accepted: 09/01/2021] [Indexed: 12/29/2022] Open
Abstract
Epstein-Barr virus (EBV) is a human herpesvirus associated with human cancers worldwide. Ex vivo, the virus efficiently infects resting human B lymphocytes and induces their continuous proliferation. This process is accompanied by a global reprogramming of cellular gene transcription. However, very little is known on the impact of EBV infection on the regulation of alternative splicing, a pivotal mechanism that plays an essential role in cell fate determination and is often deregulated in cancer. In this study, we have developed a systematic time-resolved analysis of cellular mRNA splice variant expression during EBV infection of resting B lymphocytes. Our results reveal that major modifications of alternative splice variant expression appear as early as day 1 post-infection and suggest that splicing regulation provides—besides transcription—an additional mechanism of gene expression regulation at the onset of B cell activation and proliferation. We also report a role for the viral proteins, EBNA2 and EBNA-LP, in the modulation of specific alternative splicing events and reveal a previously unknown function for EBNA-LP—together with the RBM4 splicing factor—in the alternative splicing regulation of two important modulators of cell proliferation and apoptosis respectively, NUMB and BCL-X.
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Affiliation(s)
- Evelyne Manet
- CIRI, Centre International de Recherche en Infectiologie, RNA Expression in Viruses and Eukaryotes Group, Univ Lyon, Université Claude Bernard Lyon I, INSERM U1111, CNRS UMR5308, ENS Lyon, Lyon F-69007, France
| | | | - Fabrice Mure
- CIRI, Centre International de Recherche en Infectiologie, RNA Expression in Viruses and Eukaryotes Group, Univ Lyon, Université Claude Bernard Lyon I, INSERM U1111, CNRS UMR5308, ENS Lyon, Lyon F-69007, France
| | - Paulina Mrozek-Gorska
- Research Unit Gene Vectors, Helmholtz Zentrum München, German Research Center for Environmental Health and German Center for Infection Research, D-81377 Munich, Germany
| | - Florian Roisné-Hamelin
- CIRI, Centre International de Recherche en Infectiologie, RNA Expression in Viruses and Eukaryotes Group, Univ Lyon, Université Claude Bernard Lyon I, INSERM U1111, CNRS UMR5308, ENS Lyon, Lyon F-69007, France
| | - Wolfgang Hammerschmidt
- Research Unit Gene Vectors, Helmholtz Zentrum München, German Research Center for Environmental Health and German Center for Infection Research, D-81377 Munich, Germany
| | | | - Henri Gruffat
- CIRI, Centre International de Recherche en Infectiologie, RNA Expression in Viruses and Eukaryotes Group, Univ Lyon, Université Claude Bernard Lyon I, INSERM U1111, CNRS UMR5308, ENS Lyon, Lyon F-69007, France
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38
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The Expanding Role of Alternative Splicing in Vascular Smooth Muscle Cell Plasticity. Int J Mol Sci 2021; 22:ijms221910213. [PMID: 34638554 PMCID: PMC8508619 DOI: 10.3390/ijms221910213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/15/2021] [Accepted: 09/18/2021] [Indexed: 12/21/2022] Open
Abstract
Vascular smooth muscle cells (VSMCs) display extraordinary phenotypic plasticity. This allows them to differentiate or dedifferentiate, depending on environmental cues. The ability to ‘switch’ between a quiescent contractile phenotype to a highly proliferative synthetic state renders VSMCs as primary mediators of vascular repair and remodelling. When their plasticity is pathological, it can lead to cardiovascular diseases such as atherosclerosis and restenosis. Coinciding with significant technological and conceptual innovations in RNA biology, there has been a growing focus on the role of alternative splicing in VSMC gene expression regulation. Herein, we review how alternative splicing and its regulatory factors are involved in generating protein diversity and altering gene expression levels in VSMC plasticity. Moreover, we explore how recent advancements in the development of splicing-modulating therapies may be applied to VSMC-related pathologies.
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39
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Ren P, Lu L, Cai S, Chen J, Lin W, Han F. Alternative Splicing: A New Cause and Potential Therapeutic Target in Autoimmune Disease. Front Immunol 2021; 12:713540. [PMID: 34484216 PMCID: PMC8416054 DOI: 10.3389/fimmu.2021.713540] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 07/29/2021] [Indexed: 11/13/2022] Open
Abstract
Alternative splicing (AS) is a complex coordinated transcriptional regulatory mechanism. It affects nearly 95% of all protein-coding genes and occurs in nearly all human organs. Aberrant alternative splicing can lead to various neurological diseases and cancers and is responsible for aging, infection, inflammation, immune and metabolic disorders, and so on. Though aberrant alternative splicing events and their regulatory mechanisms are widely recognized, the association between autoimmune disease and alternative splicing has not been extensively examined. Autoimmune diseases are characterized by the loss of tolerance of the immune system towards self-antigens and organ-specific or systemic inflammation and subsequent tissue damage. In the present review, we summarized the most recent reports on splicing events that occur in the immunopathogenesis of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and attempted to clarify the role that splicing events play in regulating autoimmune disease progression. We also identified the changes that occur in splicing factor expression. The foregoing information might improve our understanding of autoimmune diseases and help develop new diagnostic and therapeutic tools for them.
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Affiliation(s)
- Pingping Ren
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Nephropathy, Zhejiang Province, Hangzhou, China.,Institute of Nephropathy, Zhejiang University, Hangzhou, China
| | - Luying Lu
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Nephropathy, Zhejiang Province, Hangzhou, China.,Institute of Nephropathy, Zhejiang University, Hangzhou, China
| | - Shasha Cai
- Department of Nephrology, The First People's Hospital of Wenling, Taizhou, China
| | - Jianghua Chen
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Nephropathy, Zhejiang Province, Hangzhou, China.,Institute of Nephropathy, Zhejiang University, Hangzhou, China
| | - Weiqiang Lin
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Nephropathy, Zhejiang Province, Hangzhou, China.,Institute of Nephropathy, Zhejiang University, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University of Medicine, Hangzhou, China
| | - Fei Han
- Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Nephropathy, Zhejiang Province, Hangzhou, China.,Institute of Nephropathy, Zhejiang University, Hangzhou, China
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40
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Extensive Changes in Transcription Dynamics Reflected on Alternative Splicing Events in Systemic Lupus Erythematosus Patients. Genes (Basel) 2021; 12:genes12081260. [PMID: 34440434 PMCID: PMC8392844 DOI: 10.3390/genes12081260] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 11/17/2022] Open
Abstract
In addition to increasing the complexity of the transcriptional output, alternative RNA splicing can lead to the reduction of mRNA translation or the production of non-functional or malfunctional proteins, thus representing a vital component of the gene regulation process. Herein, we set out to detect and characterize alternative splicing events that occur in whole-blood samples of patients with Systemic Lupus Erythematosus (SLE) as compared to healthy counterparts. Through the implementation of a computational pipeline on published RNA-sequencing data, we identified extensive changes in the transcription dynamics affecting a large number of genes. We found a predominance of intron retention events, with the majority introducing premature stop codons, suggestive of gene repression, in both inactive and active SLE patient samples. Alternative splicing affected a distinct set of genes from the ones detected as differentially expressed in the same comparisons, while alternatively spliced genes tended to reside in genome areas associated with increased gene co-expression. Functional analysis of genes affected by alternative splicing pointed towards particular functions related to metabolism and histone acetylation as of potential interest. Together, our findings underline the importance of incorporating alternative splicing analyses in the context of molecular characterization of complex diseases such as SLE.
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41
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Majewska K, Wróblewska-Ankiewicz P, Rudzka M, Hyjek-Składanowska M, Gołębiewski M, Smoliński DJ, Kołowerzo-Lubnau A. Different Patterns of mRNA Nuclear Retention during Meiotic Prophase in Larch Microsporocytes. Int J Mol Sci 2021; 22:8501. [PMID: 34445207 PMCID: PMC8395157 DOI: 10.3390/ijms22168501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 07/18/2021] [Accepted: 08/04/2021] [Indexed: 12/12/2022] Open
Abstract
Recent studies show a crucial role of post-transcriptional processes in the regulation of gene expression. Our research has shown that mRNA retention in the nucleus plays a significant role in such regulation. We studied larch microsporocytes during meiotic prophase, characterized by pulsatile transcriptional activity. After each pulse, the transcriptional activity is silenced, but the transcripts synthesized at this time are not exported immediately to the cytoplasm but are retained in the cell nucleus and especially in Cajal bodies, where non-fully-spliced transcripts with retained introns are accumulated. Analysis of the transcriptome of these cells and detailed analysis of the nuclear retention and transport dynamics of several mRNAs revealed two main patterns of nuclear accumulation and transport. The majority of studied transcripts followed the first one, consisting of a more extended retention period and slow release to the cytoplasm. We have shown this in detail for the pre-mRNA and mRNA encoding RNA pol II subunit 10. In this pre-mRNA, a second (retained) intron is posttranscriptionally spliced at a precisely defined time. Fully mature mRNA is then released into the cytoplasm, where the RNA pol II complexes are produced. These proteins are necessary for transcription in the next pulse to occur.mRNAs encoding translation factors and SERRATE followed the second pattern, in which the retention period was shorter and transcripts were rapidly transferred to the cytoplasm. The presence of such a mechanism in various cell types from a diverse range of organisms suggests that it is an evolutionarily conserved mechanism of gene regulation.
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Affiliation(s)
- Karolina Majewska
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
| | - Patrycja Wróblewska-Ankiewicz
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
| | - Magda Rudzka
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
| | - Malwina Hyjek-Składanowska
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
| | - Marcin Gołębiewski
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
- Department of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland
| | - Dariusz Jan Smoliński
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
| | - Agnieszka Kołowerzo-Lubnau
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland; (K.M.); (P.W.-A.); (M.R.); (M.H.-S.)
- Centre For Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland;
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Kim CH, Park SM, Lee SJ, Kim YD, Jang SH, Woo SM, Kwon TK, Park ZY, Chung IJ, Kim HR, Jun CD. NSrp70 is a lymphocyte-essential splicing factor that controls thymocyte development. Nucleic Acids Res 2021; 49:5760-5778. [PMID: 34037780 PMCID: PMC8191771 DOI: 10.1093/nar/gkab389] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 04/04/2021] [Accepted: 04/30/2021] [Indexed: 11/21/2022] Open
Abstract
Alternative pre-mRNA splicing is a critical step to generate multiple transcripts, thereby dramatically enlarging the proteomic diversity. Thus, a common feature of most alternative splicing factor knockout models is lethality. However, little is known about lineage-specific alternative splicing regulators in a physiological setting. Here, we report that NSrp70 is selectively expressed in developing thymocytes, highest at the double-positive (DP) stage. Global splicing and transcriptional profiling revealed that NSrp70 regulates the cell cycle and survival of thymocytes by controlling the alternative processing of various RNA splicing factors, including the oncogenic splicing factor SRSF1. A conditional-knockout of Nsrp1 (NSrp70-cKO) using CD4Cre developed severe defects in T cell maturation to single-positive thymocytes, due to insufficient T cell receptor (TCR) signaling and uncontrolled cell growth and death. Mice displayed severe peripheral lymphopenia and could not optimally control tumor growth. This study establishes a model to address the function of lymphoid-lineage-specific alternative splicing factor NSrp70 in a thymic T cell developmental pathway.
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Affiliation(s)
- Chang-Hyun Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea.,Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Sang-Moo Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea.,Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Sun-Jae Lee
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Young-Dae Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea.,Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Se-Hwan Jang
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Seon-Min Woo
- Department of Immunology, School of Medicine, Keimyung University, Daegu 42601, Korea
| | - Taeg-Kyu Kwon
- Department of Immunology, School of Medicine, Keimyung University, Daegu 42601, Korea
| | - Zee-Yong Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Ik-Joo Chung
- Department of Hematology-Oncology, Immunotherapy Innovation Center, Chonnam National University Medical School, Hwasun 58128, Korea
| | - Hye-Ran Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea.,Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Chang-Duk Jun
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea.,Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
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43
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Li F, Hu Q, Chen F, Jiang JF. Transcriptome analysis reveals Vernalization is independent of cold acclimation in Arabidopsis. BMC Genomics 2021; 22:462. [PMID: 34154522 PMCID: PMC8218483 DOI: 10.1186/s12864-021-07763-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/31/2021] [Indexed: 01/08/2023] Open
Abstract
Background Through vernalization, plants achieve flowering competence by sensing prolonged cold exposure (constant exposure approximately 2-5 °C). During this process, plants initiate defense responses to endure cold conditions. Here, we conducted transcriptome analysis of Arabidopsis plants subjected to prolonged cold exposure (6 weeks) to explore the physiological dynamics of vernalization and uncover the relationship between vernalization and cold stress. Results Time-lag initiation of the two pathways and weighted gene co-expression network analysis (WGCNA) revealed that vernalization is independent of cold acclimation. Moreover, WGCNA revealed three major networks involving ethylene and jasmonic acid response, cold acclimation, and chromatin modification in response to prolonged cold exposure. Finally, throughout vernalization, the cold stress response is regulated via an alternative splicing-mediated mechanism. Conclusion These findings illustrate a comprehensive picture of cold stress- and vernalization-mediated global changes in Arabidopsis. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07763-3.
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Affiliation(s)
- Fei Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Qian Hu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Fadi Chen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jia Fu Jiang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
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44
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Dumbović G, Braunschweig U, Langner HK, Smallegan M, Biayna J, Hass EP, Jastrzebska K, Blencowe B, Cech TR, Caruthers MH, Rinn JL. Nuclear compartmentalization of TERT mRNA and TUG1 lncRNA is driven by intron retention. Nat Commun 2021; 12:3308. [PMID: 34083519 PMCID: PMC8175569 DOI: 10.1038/s41467-021-23221-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 04/07/2021] [Indexed: 12/27/2022] Open
Abstract
The spatial partitioning of the transcriptome in the cell is an important form of gene-expression regulation. Here, we address how intron retention influences the spatio-temporal dynamics of transcripts from two clinically relevant genes: TERT (Telomerase Reverse Transcriptase) pre-mRNA and TUG1 (Taurine-Upregulated Gene 1) lncRNA. Single molecule RNA FISH reveals that nuclear TERT transcripts uniformly and robustly retain specific introns. Our data suggest that the splicing of TERT retained introns occurs during mitosis. In contrast, TUG1 has a bimodal distribution of fully spliced cytoplasmic and intron-retained nuclear transcripts. We further test the functionality of intron-retention events using RNA-targeting thiomorpholino antisense oligonucleotides to block intron excision. We show that intron retention is the driving force for the nuclear compartmentalization of these RNAs. For both RNAs, altering this splicing-driven subcellular distribution has significant effects on cell viability. Together, these findings show that stable retention of specific introns can orchestrate spatial compartmentalization of these RNAs within the cell. This process reveals that modulating RNA localization via targeted intron retention can be utilized for RNA-based therapies.
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Affiliation(s)
- Gabrijela Dumbović
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA.
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, USA.
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.
| | | | - Heera K Langner
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Michael Smallegan
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, USA
- Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, CO, USA
| | - Josep Biayna
- Institute for Research in Biomedicine, Parc Científic de Barcelona, Barcelona, Spain
| | - Evan P Hass
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Katarzyna Jastrzebska
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lodz, Poland
| | | | - Thomas R Cech
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, USA
- Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, CO, USA
| | - Marvin H Caruthers
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - John L Rinn
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA.
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, USA.
- Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, CO, USA.
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45
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Diaz F, Allan CW, Markow TA, Bono JM, Matzkin LM. Gene expression and alternative splicing dynamics are perturbed in female head transcriptomes following heterospecific copulation. BMC Genomics 2021; 22:359. [PMID: 34006224 PMCID: PMC8132402 DOI: 10.1186/s12864-021-07669-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 04/27/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Despite the growing interest in the female side of copulatory interactions, the roles played by differential expression and alternative splicing mechanisms of pre-RNA on tissues outside of the reproductive tract have remained largely unknown. Here we addressed these questions in the context of con- vs heterospecific matings between Drosophila mojavensis and its sister species, D. arizonae. We analyzed transcriptional responses in female heads using an integrated investigation of genome-wide patterns of gene expression, including differential expression (DE), alternative splicing (AS) and intron retention (IR). RESULTS Our results indicated that early transcriptional responses were largely congruent between con- and heterospecific matings but are substantially perturbed over time. Conspecific matings induced functional pathways related to amino acid balance previously associated with the brain's physiology and female postmating behavior. Heterospecific matings often failed to activate regulation of some of these genes and induced expression of additional genes when compared with those of conspecifically-mated females. These mechanisms showed functional specializations with DE genes mostly linked to pathways of proteolysis and nutrient homeostasis, while AS genes were more related to photoreception and muscle assembly pathways. IR seems to play a more general role in DE regulation during the female postmating response. CONCLUSIONS We provide evidence showing that AS genes substantially perturbed by heterospecific matings in female heads evolve at slower evolutionary rates than the genome background. However, DE genes evolve at evolutionary rates similar, or even higher, than those of male reproductive genes, which highlights their potential role in sexual selection and the evolution of reproductive barriers.
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Affiliation(s)
- Fernando Diaz
- Department of Entomology, University of Arizona, Tucson, AZ, USA.
| | - Carson W Allan
- Department of Entomology, University of Arizona, Tucson, AZ, USA
| | - Therese Ann Markow
- Cinvestav UGA-Langebio, Irapuato, Guanajuato, Mexico
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, California, USA
| | - Jeremy M Bono
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, USA.
| | - Luciano M Matzkin
- Department of Entomology, University of Arizona, Tucson, AZ, USA.
- BIO5 Institute, University of Arizona, Tucson, AZ, USA.
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA.
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The RNA binding protein FgRbp1 regulates specific pre-mRNA splicing via interacting with U2AF23 in Fusarium. Nat Commun 2021; 12:2661. [PMID: 33976182 PMCID: PMC8113354 DOI: 10.1038/s41467-021-22917-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 04/05/2021] [Indexed: 02/03/2023] Open
Abstract
Precursor messenger RNA (pre-mRNA) splicing is an essential and tightly regulated process in eukaryotic cells; however, the regulatory mechanisms for the splicing are not well understood. Here, we characterize a RNA binding protein named FgRbp1 in Fusarium graminearum, a fungal pathogen of cereal crops worldwide. Deletion of FgRbp1 leads to reduced splicing efficiency in 47% of the F. graminearum intron-containing gene transcripts that are involved in various cellular processes including vegetative growth, development, and virulence. The human ortholog RBM42 is able to fully rescue the growth defects of ΔFgRbp1. FgRbp1 binds to the motif CAAGR in its target mRNAs, and interacts with the splicing factor FgU2AF23, a highly conserved protein involved in 3' splice site recognition, leading to enhanced recruitment of FgU2AF23 to the target mRNAs. This study demonstrates that FgRbp1 is a splicing regulator and regulates the pre-mRNA splicing in a sequence-dependent manner in F. graminearum.
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47
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Bressan RB, Southgate B, Ferguson KM, Blin C, Grant V, Alfazema N, Wills JC, Marques-Torrejon MA, Morrison GM, Ashmore J, Robertson F, Williams CAC, Bradley L, von Kriegsheim A, Anderson RA, Tomlinson SR, Pollard SM. Regional identity of human neural stem cells determines oncogenic responses to histone H3.3 mutants. Cell Stem Cell 2021; 28:877-893.e9. [PMID: 33631116 PMCID: PMC8110245 DOI: 10.1016/j.stem.2021.01.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/22/2020] [Accepted: 01/20/2021] [Indexed: 01/06/2023]
Abstract
Point mutations within the histone H3.3 are frequent in aggressive childhood brain tumors known as pediatric high-grade gliomas (pHGGs). Intriguingly, distinct mutations arise in discrete anatomical regions: H3.3-G34R within the forebrain and H3.3-K27M preferentially within the hindbrain. The reasons for this contrasting etiology are unknown. By engineering human fetal neural stem cell cultures from distinct brain regions, we demonstrate here that cell-intrinsic regional identity provides differential responsiveness to each mutant that mirrors the origins of pHGGs. Focusing on H3.3-G34R, we find that the oncohistone supports proliferation of forebrain cells while inducing a cytostatic response in the hindbrain. Mechanistically, H3.3-G34R does not impose widespread transcriptional or epigenetic changes but instead impairs recruitment of ZMYND11, a transcriptional repressor of highly expressed genes. We therefore propose that H3.3-G34R promotes tumorigenesis by focally stabilizing the expression of key progenitor genes, thereby locking initiating forebrain cells into their pre-existing immature state.
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Affiliation(s)
- Raul Bardini Bressan
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Biotech Research and Innovation Centre, University of Copenhagen, Copenhagen 2200, Denmark
| | - Benjamin Southgate
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Kirsty M Ferguson
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Carla Blin
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Vivien Grant
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Neza Alfazema
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Jimi C Wills
- Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Maria Angeles Marques-Torrejon
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Gillian M Morrison
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - James Ashmore
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Faye Robertson
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Charles A C Williams
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Leanne Bradley
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Alex von Kriegsheim
- Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK
| | - Richard A Anderson
- MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Simon R Tomlinson
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Institute for Stem Cell Research, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Steven M Pollard
- Centre for Regenerative Medicine and Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK; Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh EH4 2XR, UK.
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48
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Patro CPK, Nousome D, Lai RK. Meta-Analyses of Splicing and Expression Quantitative Trait Loci Identified Susceptibility Genes of Glioma. Front Genet 2021; 12:609657. [PMID: 33936159 PMCID: PMC8081720 DOI: 10.3389/fgene.2021.609657] [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: 09/24/2020] [Accepted: 03/09/2021] [Indexed: 12/13/2022] Open
Abstract
Background The functions of most glioma risk alleles are unknown. Very few studies had evaluated expression quantitative trait loci (eQTL), and insights of susceptibility genes were limited due to scarcity of available brain tissues. Moreover, no prior study had examined the effect of glioma risk alleles on alternative RNA splicing. Objective This study explored splicing quantitative trait loci (sQTL) as molecular QTL and improved the power of QTL mapping through meta-analyses of both cis eQTL and sQTL. Methods We first evaluated eQTLs and sQTLs of the CommonMind Consortium (CMC) and Genotype-Tissue Expression Project (GTEx) using genotyping, or whole-genome sequencing and RNA-seq data. Alternative splicing events were characterized using an annotation-free method that detected intron excision events. Then, we conducted meta-analyses by pooling the eQTL and sQTL results of CMC and GTEx using the inverse variance-weighted model. Afterward, we integrated QTL meta-analysis results (Q < 0.05) with the Glioma International Case Control Study (GICC) GWAS meta-analysis (case:12,496, control:18,190), using a summary statistics-based mendelian randomization (SMR) method. Results Between CMC and GTEx, we combined the QTL data of 354 unique individuals of European ancestry. SMR analyses revealed 15 eQTLs in 11 loci and 32 sQTLs in 9 loci relevant to glioma risk. Two loci only harbored sQTLs (1q44 and 16p13.3). In seven loci, both eQTL and sQTL coexisted (2q33.3, 7p11.2, 11q23.3 15q24.2, 16p12.1, 20q13.33, and 22q13.1), but the target genes were different for five of these seven loci. Three eQTL loci (9p21.3, 20q13.33, and 22q13.1) and 4 sQTL loci (11q23.3, 16p13.3, 16q12.1, and 20q13.33) harbored multiple target genes. Eight target genes of sQTLs (C2orf80, SEC61G, TMEM25, PHLDB1, RP11-161M6.2, HEATR3, RTEL1-TNFRSF6B, and LIME1) had multiple alternatively spliced transcripts. Conclusion Our study revealed that the regulation of transcriptome by glioma risk alleles is complex, with the potential for eQTL and sQTL jointly affecting gliomagenesis in risk loci. QTLs of many loci involved multiple target genes, some of which were specific to alternative splicing. Therefore, quantitative trait loci that evaluate only total gene expression will miss many important target genes.
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Affiliation(s)
- C Pawan K Patro
- Department of Neurology and Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, CA, United States
| | - Darryl Nousome
- Center for Prostate Disease Research, Department of Surgery, Uniformed Services University of the Health Sciences, Rockville, MD, United States
| | | | - Rose K Lai
- Department of Neurology and Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, Los Angeles, CA, United States
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49
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Gordon JM, Phizicky DV, Neugebauer KM. Nuclear mechanisms of gene expression control: pre-mRNA splicing as a life or death decision. Curr Opin Genet Dev 2021; 67:67-76. [PMID: 33291060 PMCID: PMC8084925 DOI: 10.1016/j.gde.2020.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/26/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023]
Abstract
Thousands of genes produce polyadenylated mRNAs that still contain one or more introns. These transcripts are known as retained intron RNAs (RI-RNAs). In the past 10 years, RI-RNAs have been linked to post-transcriptional alternative splicing in a variety of developmental contexts, but they can also be dead-end products fated for RNA decay. Here we discuss the role of intron retention in shaping gene expression programs, as well as recent evidence suggesting that the biogenesis and fate of RI-RNAs is regulated by nuclear organization. We discuss the possibility that proximity of RNA to nuclear speckles - biomolecular condensates that are highly enriched in splicing factors and other RNA binding proteins - is associated with choices ranging from efficient co-transcriptional splicing, export and stability to regulated post-transcriptional splicing and possible vulnerability to decay.
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Affiliation(s)
- Jackson M Gordon
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA
| | - David V Phizicky
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.
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50
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Panfili E, Mondanelli G, Orabona C, Belladonna ML, Gargaro M, Fallarino F, Orecchini E, Prontera P, Proietti E, Frontino G, Tirelli E, Iacono A, Vacca C, Puccetti P, Grohmann U, Esposito S, Pallotta MT. Novel mutations in the WFS1 gene are associated with Wolfram syndrome and systemic inflammation. Hum Mol Genet 2021; 30:265-276. [PMID: 33693650 PMCID: PMC8091036 DOI: 10.1093/hmg/ddab040] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 02/06/2023] Open
Abstract
Mutations in the WFS1 gene, encoding wolframin (WFS1), cause endoplasmic reticulum (ER) stress and are associated with a rare autosomal-recessive disorder known as Wolfram syndrome (WS). WS is clinically characterized by childhood-onset diabetes mellitus, optic atrophy, deafness, diabetes insipidus and neurological signs. We identified two novel WFS1 mutations in a patient with WS, namely, c.316-1G > A (in intron 3) and c.757A > T (in exon 7). Both mutations, located in the N-terminal region of the protein, were predicted to generate a truncated and inactive form of WFS1. We found that although the WFS1 protein was not expressed in peripheral blood mononuclear cells (PBMCs) of the proband, no constitutive ER stress activation could be detected in those cells. In contrast, WS proband’s PBMCs produced very high levels of proinflammatory cytokines (i.e. TNF-α, IL-1β, and IL-6) in the absence of any stimulus. WFS1 silencing in PBMCs from control subjects by means of small RNA interference also induced a pronounced proinflammatory cytokine profile. The same cytokines were also significantly higher in sera from the WS patient as compared to matched healthy controls. Moreover, the chronic inflammatory state was associated with a dominance of proinflammatory T helper 17 (Th17)-type cells over regulatory T (Treg) lymphocytes in the WS PBMCs. The identification of a state of systemic chronic inflammation associated with WFS1 deficiency may pave the way to innovative and personalized therapeutic interventions in WS.
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Affiliation(s)
- Eleonora Panfili
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Giada Mondanelli
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Ciriana Orabona
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Maria L Belladonna
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Marco Gargaro
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Francesca Fallarino
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Elena Orecchini
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Paolo Prontera
- Medical Genetics Unit, University-Hospital "Santa Maria della Misericordia", Perugia, 06132, Italy
| | - Elisa Proietti
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Giulio Frontino
- Department of Pediatrics, Diabetes Research Institute, IRCCS San Raffaele Hospital, Milan, 20132, Italy
| | - Eva Tirelli
- Department of Pediatrics, Diabetes Research Institute, IRCCS San Raffaele Hospital, Milan, 20132, Italy
| | - Alberta Iacono
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Carmine Vacca
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Paolo Puccetti
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
| | - Ursula Grohmann
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy.,Visiting Professor, Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Susanna Esposito
- Pediatric Clinic Pietro Barilla Children's Hospital, Department of Medicine and Surgery, Università di Parma, Parma, 43126, Italy
| | - Maria T Pallotta
- Department of Medicine and Surgery, University of Perugia, Perugia, 06132, Italy
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