1
|
Liu L, Manley JL. Modulation of diverse biological processes by CPSF, the master regulator of mRNA 3' ends. RNA (NEW YORK, N.Y.) 2024; 30:1122-1140. [PMID: 38986572 PMCID: PMC11331416 DOI: 10.1261/rna.080108.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 06/27/2024] [Indexed: 07/12/2024]
Abstract
The cleavage and polyadenylation specificity factor (CPSF) complex plays a central role in the formation of mRNA 3' ends, being responsible for the recognition of the poly(A) signal sequence, the endonucleolytic cleavage step, and recruitment of poly(A) polymerase. CPSF has been extensively studied for over three decades, and its functions and those of its individual subunits are becoming increasingly well-defined, with much current research focusing on the impact of these proteins on the normal functioning or disease/stress states of cells. In this review, we provide an overview of the general functions of CPSF and its subunits, followed by a discussion of how they exert their functions in a surprisingly diverse variety of biological processes and cellular conditions. These include transcription termination, small RNA processing, and R-loop prevention/resolution, as well as more generally cancer, differentiation/development, and infection/immunity.
Collapse
Affiliation(s)
- Lizhi Liu
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - James L Manley
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| |
Collapse
|
2
|
Kakoulidis P, Vlachos IS, Thanos D, Blatch GL, Emiris IZ, Anastasiadou E. Identifying and profiling structural similarities between Spike of SARS-CoV-2 and other viral or host proteins with Machaon. Commun Biol 2023; 6:752. [PMID: 37468602 PMCID: PMC10356814 DOI: 10.1038/s42003-023-05076-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 06/26/2023] [Indexed: 07/21/2023] Open
Abstract
Using protein structure to predict function, interactions, and evolutionary history is still an open challenge, with existing approaches relying extensively on protein homology and families. Here, we present Machaon, a data-driven method combining orientation invariant metrics on phi-psi angles, inter-residue contacts and surface complexity. It can be readily applied on whole structures or segments-such as domains and binding sites. Machaon was applied on SARS-CoV-2 Spike monomers of native, Delta and Omicron variants and identified correlations with a wide range of viral proteins from close to distant taxonomy ranks, as well as host proteins, such as ACE2 receptor. Machaon's meta-analysis of the results highlights structural, chemical and transcriptional similarities between the Spike monomer and human proteins, indicating a multi-level viral mimicry. This extended analysis also revealed relationships of the Spike protein with biological processes such as ubiquitination and angiogenesis and highlighted different patterns in virus attachment among the studied variants. Available at: https://machaonweb.com .
Collapse
Affiliation(s)
- Panos Kakoulidis
- Department of Informatics and Telecommunications, National and Kapodistrian University of Athens, Ilisia, 157 84, Athens, Greece
- Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou St., 115 27, Athens, Greece
| | - Ioannis S Vlachos
- Broad Institute of MIT and Harvard, Merkin Building, 415 Main St., Cambridge, MA, 02142, USA
- Cancer Research Institute, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA, 02215, USA
- Department of Pathology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA, 02215, USA
- Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA
- Spatial Technologies Unit, Harvard Medical School Initiative for RNA Medicine, Dana Building, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA, 02215, USA
| | - Dimitris Thanos
- Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou St., 115 27, Athens, Greece
| | - Gregory L Blatch
- Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, PO Box 94, Makhanda (Grahamstown) 6140, Eastern Cape, South Africa
- Biomedical and Drug Discovery Research Group, Faculty of Health Sciences, Higher Colleges of Technology, PO 25026, Sharjah, UAE
- Institute for Health and Sport, Victoria University, Melbourne, PO Box 14428, VIC 8001, Melbourne, Australia
- The Vice Chancellery, The University of Notre Dame Australia, PO Box 1225, WA 6959, Fremantle, Australia
| | - Ioannis Z Emiris
- Department of Informatics and Telecommunications, National and Kapodistrian University of Athens, Ilisia, 157 84, Athens, Greece
- ATHENA Research and Innovation Center, Artemidos 6 & Epidavrou 15125, Marousi, Greece
| | - Ema Anastasiadou
- Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou St., 115 27, Athens, Greece.
| |
Collapse
|
3
|
Nagasawa CK, Garcia-Blanco MA. Early Splicing Complexes and Human Disease. Int J Mol Sci 2023; 24:11412. [PMID: 37511171 PMCID: PMC10379813 DOI: 10.3390/ijms241411412] [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: 06/18/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Over the last decade, our understanding of spliceosome structure and function has significantly improved, refining the study of the impact of dysregulated splicing on human disease. As a result, targeted splicing therapeutics have been developed, treating various diseases including spinal muscular atrophy and Duchenne muscular dystrophy. These advancements are very promising and emphasize the critical role of proper splicing in maintaining human health. Herein, we provide an overview of the current information on the composition and assembly of early splicing complexes-commitment complex and pre-spliceosome-and their association with human disease.
Collapse
Affiliation(s)
- Chloe K. Nagasawa
- Human Pathophysiology and Translational Medicine Program, Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX 77555-5302, USA;
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-5302, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA 22903-2628, USA
| | - Mariano A. Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-5302, USA
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA 22903-2628, USA
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555-5302, USA
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555-5302, USA
| |
Collapse
|
4
|
Hirano M, Galarza-Muñoz G, Nagasawa C, Schott G, Wang L, Antonia AL, Jain V, Yu X, Widen SG, Briggs FBS, Gregory SG, Ko DC, Fagg WS, Bradrick S, Garcia-Blanco MA. The RNA helicase DDX39B activates FOXP3 RNA splicing to control T regulatory cell fate. eLife 2023; 12:e76927. [PMID: 37261960 PMCID: PMC10234631 DOI: 10.7554/elife.76927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 05/09/2023] [Indexed: 06/03/2023] Open
Abstract
Genes associated with increased susceptibility to multiple sclerosis (MS) have been identified, but their functions are incompletely understood. One of these genes codes for the RNA helicase DExD/H-Box Polypeptide 39B (DDX39B), which shows genetic and functional epistasis with interleukin-7 receptor-α gene (IL7R) in MS-risk. Based on evolutionary and functional arguments, we postulated that DDX39B enhances immune tolerance thereby decreasing MS risk. Consistent with such a role we show that DDX39B controls the expression of many MS susceptibility genes and important immune-related genes. Among these we identified Forkhead Box P3 (FOXP3), which codes for the master transcriptional factor in CD4+/CD25+ T regulatory cells. DDX39B knockdown led to loss of immune-regulatory and gain of immune-effector expression signatures. Splicing of FOXP3 introns, which belong to a previously unrecognized type of introns with C-rich polypyrimidine tracts, was exquisitely sensitive to DDX39B levels. Given the importance of FOXP3 in autoimmunity, this work cements DDX39B as an important guardian of immune tolerance.
Collapse
Affiliation(s)
- Minato Hirano
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- National Research Center for the Control and Prevention of Infectious Disease, Nagasaki UniversityNagasakiJapan
| | - Gaddiel Galarza-Muñoz
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Autoimmunity Biological SolutionsGalvestonUnited States
| | - Chloe Nagasawa
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Human Pathophysiology and Translational Medicine Program, Institute for Translational Sciences, University of Texas Medical BranchGalvestonUnited States
| | - Geraldine Schott
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
| | - Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
| | - Vaibhav Jain
- Duke Molecular Physiology Institute, Duke UniversityDurhamUnited States
| | - Xiaoying Yu
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Department of Preventive Medicine and Population Health, University of Texas Medical BranchGalvestonUnited States
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
| | - Farren BS Briggs
- Department of Population and Quantitative Health Sciences, School of Medicine, Case Western Reserve UniversityClevelandUnited States
| | - Simon G Gregory
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
- Duke Molecular Physiology Institute, Duke UniversityDurhamUnited States
- Department of Neurology, Duke University School of MedicineDurhamUnited States
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
- Division of Infectious Diseases, Department of Medicine, Duke UniversityDurhamUnited States
| | - William S Fagg
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Transplant Division, Department of Surgery, University of Texas Medical BranchGalvestonUnited States
| | - Shelton Bradrick
- Institute of Human Infections and Immunity, University of Texas Medical BranchGalvestonUnited States
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Department of Internal Medicine, University of Texas Medical BranchGalvestonUnited States
- Department of Microbiology, Immunology and Cancer Biology, University of VirginiaCharlottesvilleUnited States
| |
Collapse
|
5
|
Kang W, Yang Y, Chen C, Yu C. CPSF1 positively regulates NSDHL by alternative polyadenylation and promotes gastric cancer progression. Am J Cancer Res 2022; 12:4566-4583. [PMID: 36381317 PMCID: PMC9641403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023] Open
Abstract
Gastric cancer (GC) is a common malignancies with unfavourable prognosis. As one of the most common RNA modifications in nature, alternative polyadenylation (APA) plays a critical role in the progression of carcinomas. CPSF1 is a critical APA-related factor and is involved in many cancers. Nevertheless, the roles and underlying mechanisms of CPSF1 remain unclear in GC. In this work, we identified that CPSF1 is significantly upregulated in GC and that high CPSF1 expression indicates an unfavourable prognosis in GC patients. Moreover, CPSF1 expression levels were closely associated with tumour size, TNM stage and lymph node metastasis. CPSF1 depletion dramatically weakened GC cell proliferation and metastasis. We then performed RNA sequencing and found numerous downstream genes involved the regulation of CPSF1 with remarkable changes in 3'UTR length, among which NSDHL was positively regulated by CPSF1 and promoted GC progression. In addition, rescue assays demonstrated that NSDHL mediated the carcinogenic effect of CPSF1, and this process potentially involved APA. Therefore, this study showed that CPSF1 promotes GC progression, at least in part, by enhancing NSDHL and offered new insights into therapeutic targets for GC.
Collapse
|
6
|
Galarza-Muñoz G, Kennedy-Boone D, Schott G, Bradrick SS, Garcia-Blanco MA. Antisense modulation of IL7R splicing to control sIL7R expression in human CD4 + T cells. RNA (NEW YORK, N.Y.) 2022; 28:1058-1073. [PMID: 35613883 PMCID: PMC9297843 DOI: 10.1261/rna.079137.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
The interleukin 7 receptor (IL7R) is strongly associated with increased risk to develop multiple sclerosis (MS), an autoimmune disease of the central nervous system, and this association is likely driven by up-regulation of the soluble isoform of IL7R (sIL7R). Expression of sIL7R is determined by exclusion of the alternative exon 6 from IL7R transcripts, and our previous work revealed that the MS risk allele of the SNP rs6897932 within this exon enhances the expression of sIL7R by promoting exclusion of exon 6. sIL7R potentiates the activity of IL7, leading to enhanced expansion of T cells and increased disability in the experimental autoimmune encephalomyelitis (EAE) murine model of MS. This role in modulating T cell-driven immunity positions sIL7R as an attractive therapeutic target whose expression could be reduced for treatment of MS or increased for treatment of cancers. In this study, we identified novel antisense oligonucleotides (ASOs) that effectively control the inclusion (anti-sIL7R ASOs) or exclusion (pro-sIL7R ASOs) of this exon in a dose-dependent fashion. These ASOs provided excellent control of exon 6 splicing and sIL7R secretion in human primary CD4+ T cells. Supporting their potential for therapeutic targeting, we showed that lead anti-sIL7R ASOs correct the enhanced exon 6 exclusion imposed by the MS risk allele of rs6897932, whereas lead pro-sIL7R ASOs phenocopy it. The data presented here form the foundation for future preclinical studies that will test the therapeutic potential of these ASOs in MS and immuno-oncology.
Collapse
Affiliation(s)
- Gaddiel Galarza-Muñoz
- Autoimmunity BioSolutions, Galveston, Texas 77550, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77550, USA
- Department of Neurology, University of Texas Medical Branch, Galveston, Texas 77550, USA
| | - Debbie Kennedy-Boone
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77550, USA
| | - Geraldine Schott
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77550, USA
| | - Shelton S Bradrick
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77550, USA
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas 77550, USA
| | - Mariano A Garcia-Blanco
- Autoimmunity BioSolutions, Galveston, Texas 77550, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77550, USA
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas 77550, USA
| |
Collapse
|
7
|
Xia L, Han Q, Duan X, Zhu Y, Pan J, Dong B, Xia W, Xue W, Sha J. m6A-induced repression of SIAH1 facilitates alternative splicing of androgen receptor variant 7 by regulating CPSF1. MOLECULAR THERAPY - NUCLEIC ACIDS 2022; 28:219-230. [PMID: 35402071 PMCID: PMC8965770 DOI: 10.1016/j.omtn.2022.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/12/2022] [Indexed: 01/22/2023]
Affiliation(s)
- Lei Xia
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Qing Han
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Xuehui Duan
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Yinjie Zhu
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Jiahua Pan
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Baijun Dong
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Weiliang Xia
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
| | - Wei Xue
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
- Corresponding author. Wei Xue, Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle road, Shanghai 200001, China.
| | - Jianjun Sha
- Department of Urology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200001, People’s Republic of China
- Corresponding author. Jianjun Sha, Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle road, Shanghai 200001, China.
| |
Collapse
|
8
|
Bustos Plonka F, Sosa LJ, Quiroga S. Sec3 exocyst component knockdown inhibits axonal formation and cortical neuronal migration during brain cortex development. J Neurochem 2021; 160:203-217. [PMID: 34862972 DOI: 10.1111/jnc.15554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 10/27/2021] [Accepted: 11/25/2021] [Indexed: 12/22/2022]
Abstract
Neurons are the largest known cells, with complex and highly polarized morphologies and consist of a cell body (soma), several dendrites, and a single axon. The establishment of polarity necessitates initial axonal outgrowth in concomitance with the addition of new membrane to the axon's plasmalemma. Axolemmal expansion occurs by exocytosis of plasmalemmal precursor vesicles primarily at the neuronal growth cone membrane. The multiprotein exocyst complex drives spatial location and specificity of vesicle fusion at plasma membrane. However, the specific participation of its different proteins on neuronal differentiation has not been fully established. In the present work we analyzed the role of Sec3, a prominent exocyst complex protein on neuronal differentiation. Using mice hippocampal primary cultures, we determined that Sec3 is expressed in neurons at early stages prior to neuronal polarization. Furthermore, we determined that silencing of Sec3 in mice hippocampal neurons in culture precluded polarization. Moreover, using in utero electroporation experiments, we determined that Sec3 knockdown affected cortical neurons migration and morphology during neocortex formation. Our results demonstrate that the exocyst complex protein Sec3 plays an important role in axon formation in neuronal differentiation and the migration of neuronal progenitors during cortex development.
Collapse
Affiliation(s)
- Florentyna Bustos Plonka
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
| | - Lucas J Sosa
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
| | - Santiago Quiroga
- Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Universidad Nacional de Córdoba y CIQUIBIC-CONICET, Córdoba, Argentina
| |
Collapse
|
9
|
Gupta M, Liu X, Teraoka SN, Wright JA, Gatti RA, Quinlan A, Concannon P. Genes affecting ionizing radiation survival identified through combined exome sequencing and functional screening. Hum Mutat 2021; 42:1124-1138. [PMID: 34153142 DOI: 10.1002/humu.24241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 05/04/2021] [Accepted: 06/13/2021] [Indexed: 11/09/2022]
Abstract
The study of genetic syndromes characterized by sensitivity to DNA damaging agents has provided important insights into the mechanisms that maintain genome stability and identified novel targets for cancer therapies. Here, we used exome sequencing to study 51 unrelated individuals with previously reported hypersensitivity to ionizing radiation as well as a range of neurologic, immunologic, and developmental features, but who did not clearly fit any previously defined genetic syndrome. Based on the combination of variant identification, computational evidence of deleteriousness, and functional screening, we identified three groups of subjects. Two subjects carried the bi-allelic loss of function variants in causative genes for known DNA damage response syndromes. Eight subjects carried the single loss of function variants in causative genes for DNA damage response syndromes, six of whom also carried predicted deleterious variants in other genes with DNA damage-related functions. Three subjects carried deleterious mutations in genes without obvious roles in DNA damage responses. However, treatment of U2OS cells with small interfering RNA targeting these genes resulted in significantly increased radiation sensitivity. Our results suggest that gene-gene interaction may contribute to ionizing radiation sensitivity as well as highlighting possible roles for several genes not obviously involved in the response to DNA damage.
Collapse
Affiliation(s)
- Meenal Gupta
- Department of Human Genetics and Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah, USA
| | - Xiangfei Liu
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Sharon N Teraoka
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Jocyndra A Wright
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| | - Richard A Gatti
- UCLA Department of Pathology and Laboratory Medicine, and Department of Human Genetics, Los Angeles, California, USA
| | - Aaron Quinlan
- Department of Human Genetics and Department of Biomedical Informatics, University of Utah, Salt Lake City, Utah, USA
| | - Patrick Concannon
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
10
|
Chen SL, Zhu ZX, Yang X, Liu LL, He YF, Yang MM, Guan XY, Wang X, Yun JP. Cleavage and Polyadenylation Specific Factor 1 Promotes Tumor Progression via Alternative Polyadenylation and Splicing in Hepatocellular Carcinoma. Front Cell Dev Biol 2021; 9:616835. [PMID: 33748106 PMCID: PMC7969726 DOI: 10.3389/fcell.2021.616835] [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: 10/13/2020] [Accepted: 02/04/2021] [Indexed: 12/24/2022] Open
Abstract
Alternative polyadenylation (APA) is an important post-transcriptional regulatory mechanism required for cleavage and polyadenylation (CPA) of the 3′ untranslated region (3′ UTR) of mRNAs. Several aberrant APA events have been reported in hepatocellular carcinoma (HCC). However, the regulatory mechanisms underlying APA remain unclear. In this study, we found that the expression of cleavage and polyadenylation specific factor 1 (CPSF1), a major component of the CPA complex, was significantly increased in HCC tissues and correlated with unfavorable survival outcomes. Knockdown of CPSF1 inhibited HCC cell proliferation and migration, whereas overexpression of CPSF1 caused the opposite effect. Based on integrative analysis of Iso-Seq and RNA-seq data from HepG2.2.15 cells, we identified a series of transcripts with differential 3′ UTR lengths following the knockdown of CPSF1. These transcripts were related to the biological functions of gene transcription, cytoskeleton maintenance, and endomembrane system transportation. Moreover, knockdown of CPSF1 induced an increase in alternative splicing (AS) events in addition to APA. Taken together, this study provides new insights into our understanding of the post-transcriptional regulatory mechanisms in HCC and implies that CPSF1 may be a potential prognostic biomarker and therapeutic target for HCC.
Collapse
Affiliation(s)
- Shi-Lu Chen
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Zhong-Xu Zhu
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Xia Yang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Li-Li Liu
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yang-Fan He
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Ming-Ming Yang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Xin-Yuan Guan
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Xin Wang
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
| | - Jing-Ping Yun
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China
| |
Collapse
|
11
|
Schott G, Galarza-Muñoz G, Trevino N, Chen X, Weirauch M, Gregory SG, Bradrick SS, Garcia-Blanco MA. U2AF2 binds IL7R exon 6 ectopically and represses its inclusion. RNA (NEW YORK, N.Y.) 2021; 27:rna.078279.120. [PMID: 33568552 PMCID: PMC8051268 DOI: 10.1261/rna.078279.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/02/2021] [Indexed: 06/03/2023]
Abstract
Interleukin 7 receptor α-chain is crucial for the development and maintenance of T cells and is genetically associated with autoimmune disorders including multiple sclerosis (MS), a demyelinating disease of the CNS. Exon 6 of IL7R encodes for the transmembrane domain of the receptor and is regulated by alternative splicing: inclusion or skipping of IL7R exon 6 results in membrane-bound or soluble IL7R isoforms, respectively. We previously identified a SNP (rs6897932) in IL7R exon 6, strongly associated with MS risk and showed that the risk allele (C) increases skipping of the exon, resulting in elevated levels of sIL7R. This has important pathological consequences as elevated levels of sIL7R has been shown to exacerbate the disease in the experimental autoimmune encephalomyelitis mouse model of MS. Understanding the regulation of exon 6 splicing provides important mechanistic insights into the pathogenesis of MS. Here we report two mechanisms by which IL7R exon 6 is controlled. First, a competition between PTBP1 and U2AF2 at the polypyrimidine tract (PPT) of intron 5, and second, an unexpected U2AF2-mediated assembly of spicing factors in the exon. We noted the presence of a branchpoint sequence (BPS) (TACTAAT or TACTAAC) within exon 6, which is stronger with the C allele. We also noted that the BPS is followed by a PPT and conjectured that silencing could be mediated by the binding of U2AF2 to that tract. In support of this model, we show that evolutionary conservation of the exonic PPT correlates well with the degree of alternative splicing of exon 6 in two non-human primate species and that U2AF2 binding to this PPT recruits U2 snRNP components to the exon. These observations provide the first explanation for the stronger silencing of IL7R exon 6 with the disease associated C allele at rs6897932.
Collapse
|
12
|
Cardamone G, Paraboschi EM, Soldà G, Cantoni C, Supino D, Piccio L, Duga S, Asselta R. Not only cancer: the long non-coding RNA MALAT1 affects the repertoire of alternatively spliced transcripts and circular RNAs in multiple sclerosis. Hum Mol Genet 2020; 28:1414-1428. [PMID: 30566690 DOI: 10.1093/hmg/ddy438] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/12/2018] [Accepted: 12/14/2018] [Indexed: 01/23/2023] Open
Abstract
Long non-coding RNAs (lncRNAs) are post-transcriptional and epigenetic regulators, whose implication in neurodegenerative and autoimmune diseases remains poorly understood. We analyzed publicly available microarray data sets to identify dysregulated lncRNAs in multiple sclerosis (MS), a neuroinflammatory autoimmune disease. We found a consistent upregulation in MS of the lncRNA MALAT1 (2.7-fold increase; meta-analysis, P = 1.3 × 10-8; 190 cases, 182 controls), known to regulate alternative splicing (AS). We confirmed MALAT1 upregulation in two independent MS cohorts (1.5-fold increase; P < 0.01; 59 cases, 50 controls). We hence performed MALAT1 overexpression/knockdown in cell lines, demonstrating that its modulation impacts on endogenous expression of splicing factors (HNRNPF and HNRNPH1) and on AS of MS-associated genes (IL7R and SP140). Minigene-based splicing assays upon MALAT1 modulation recapitulated IL7R and SP140 isoform unbalances observed in patients. RNA-sequencing of MALAT1-knockdown Jurkat cells further highlighted MALAT1 role in splicing (approximately 1100 significantly-modulated AS events) and revealed its contribution to backsplicing (approximately 50 differentially expressed circular RNAs). Our study proposes a possible novel role for MALAT1 dysregulation and the consequent AS alteration in MS pathogenesis, based on anomalous splicing/backsplicing profiles of MS-relevant genes.
Collapse
Affiliation(s)
- Giulia Cardamone
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele Milan, Italy
| | - Elvezia M Paraboschi
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele Milan, Italy
| | - Giulia Soldà
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele Milan, Italy.,Humanitas Clinical and Research Center, Rozzano Milan, Italy
| | - Claudia Cantoni
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Domenico Supino
- Humanitas Clinical and Research Center, Rozzano Milan, Italy
| | - Laura Piccio
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - Stefano Duga
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele Milan, Italy.,Humanitas Clinical and Research Center, Rozzano Milan, Italy
| | - Rosanna Asselta
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele Milan, Italy.,Humanitas Clinical and Research Center, Rozzano Milan, Italy
| |
Collapse
|
13
|
Ignatieva EV, Yurchenko AA, Voevoda MI, Yudin NS. Exome-wide search and functional annotation of genes associated in patients with severe tick-borne encephalitis in a Russian population. BMC Med Genomics 2019; 12:61. [PMID: 31122248 PMCID: PMC6533173 DOI: 10.1186/s12920-019-0503-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Tick-borne encephalitis (TBE) is a viral infectious disease caused by tick-borne encephalitis virus (TBEV). TBEV infection is responsible for a variety of clinical manifestations ranging from mild fever to severe neurological illness. Genetic factors involved in the host response to TBEV that may potentially play a role in the severity of the disease are still poorly understood. In this study, using whole-exome sequencing, we aimed to identify genetic variants and genes associated with severe forms of TBE as well as biological pathways through which the identified variants may influence the severity of the disease. Results Whole-exome sequencing data analysis was performed on 22 Russian patients with severe forms of TBE and 17 Russian individuals from the control group. We identified 2407 candidate genes harboring rare, potentially pathogenic variants in exomes of patients with TBE and not containing any rare, potentially pathogenic variants in exomes of individuals from the control group. According to DAVID tool, this set of 2407 genes was enriched with genes involved in extracellular matrix proteoglycans pathway and genes encoding proteins located at the cell periphery. A total of 154 genes/proteins from these functional groups have been shown to be involved in protein-protein interactions (PPIs) with the known candidate genes/proteins extracted from TBEVHostDB database. By ranking these genes according to the number of rare harmful minor alleles, we identified two genes (MSR1 and LMO7), harboring five minor alleles, and three genes (FLNA, PALLD, PKD1) harboring four minor alleles. When considering genes harboring genetic variants associated with severe forms of TBE at the suggestive P-value < 0.01, 46 genes containing harmful variants were identified. Out of these 46 genes, eight (MAP4, WDFY4, ACTRT2, KLHL25, MAP2K3, MBD1, OR10J1, and OR2T34) were additionally found among genes containing rare pathogenic variants identified in patients with TBE; and five genes (WDFY4,ALK, MAP4, BNIPL, EPPK1) were found to encode proteins that are involved in PPIs with proteins encoded by genes from TBEVHostDB. Three genes out of five (MAP4, EPPK1, ALK) were found to encode proteins located at cell periphery. Conclusions Whole-exome sequencing followed by systems biology approach enabled to identify eight candidate genes (MAP4, WDFY4, ACTRT2, KLHL25, MAP2K3, MBD1, OR10J1, and OR2T34) that can potentially determine predisposition to severe forms of TBE. Analyses of the genetic risk factors for severe forms of TBE revealed a significant enrichment with genes controlling extracellular matrix proteoglycans pathway as well as genes encoding components of cell periphery. Electronic supplementary material The online version of this article (10.1186/s12920-019-0503-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Elena V Ignatieva
- Laboratory of Evolutionary Bioinformatics and Theoretical Genetics, The Federal Research Center Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. .,Novosibirsk State University, Novosibirsk, 630090, Russia.
| | - Andrey A Yurchenko
- Laboratory of Infectious Disease Genomics, The Federal Research Center Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - Mikhail I Voevoda
- Novosibirsk State University, Novosibirsk, 630090, Russia.,Research Institute of Internal and Preventive Medicine-Branch of Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Novosibirsk, 630004, Russia
| | - Nikolay S Yudin
- Laboratory of Infectious Disease Genomics, The Federal Research Center Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.,Novosibirsk State University, Novosibirsk, 630090, Russia
| |
Collapse
|
14
|
Hecker M, Rüge A, Putscher E, Boxberger N, Rommer PS, Fitzner B, Zettl UK. Aberrant expression of alternative splicing variants in multiple sclerosis - A systematic review. Autoimmun Rev 2019; 18:721-732. [PMID: 31059848 DOI: 10.1016/j.autrev.2019.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 02/22/2019] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Alternative splicing is an important form of RNA processing that affects nearly all human genes. The differential expression of specific transcript and protein isoforms holds the potential of novel biomarkers for complex diseases. In this systematic review, we compiled the existing literature on aberrant alternative splicing events in multiple sclerosis (MS). METHODS A systematic literature search in the PubMed database was carried out and supplemented by screening the reference lists of the identified articles. We selected only MS-related original research studies which compared the levels of different isoforms of human protein-coding genes. A narrative synthesis of the research findings was conducted. Additionally, we performed a case-control analysis using high-density transcriptome microarray data to reevaluate the genes that were examined in the reviewed studies. RESULTS A total of 160 records were screened. Of those, 36 studies from the last two decades were included. Most commonly, peripheral blood samples were analyzed (32 studies), and PCR-based techniques were usually employed (27 studies) for measuring the expression of selected genes. Two studies used an exploratory genome-wide approach. Overall, 27 alternatively spliced genes were investigated. Nine of these genes appeared in at least two studies (CD40, CFLAR, FOXP3, IFNAR2, IL7R, MOG, PTPRC, SP140 and TNFRSF1A). The microarray data analysis confirmed differential alternative pre-mRNA splicing for 19 genes. CONCLUSIONS An altered RNA processing of genes mediating immune signaling pathways has been repeatedly implicated in MS. The analysis of individual exon-level expression patterns is stimulated by the advancement of transcriptome profiling technologies. In particular, the examination of genes encoded in MS-associated genetic regions may provide important insights into the pathogenesis of the disease and help to identify new biomarkers.
Collapse
Affiliation(s)
- Michael Hecker
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany.
| | - Annelen Rüge
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany
| | - Elena Putscher
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany
| | - Nina Boxberger
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany
| | - Paulus Stefan Rommer
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany; Medical University of Vienna, Department of Neurology, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Brit Fitzner
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany
| | - Uwe Klaus Zettl
- University of Rostock, Department of Neurology, Division of Neuroimmunology, Gehlsheimer Str. 20, 18147 Rostock, Germany
| |
Collapse
|
15
|
MacDonald CC. Tissue-specific mechanisms of alternative polyadenylation: Testis, brain, and beyond (2018 update). WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1526. [PMID: 30816016 PMCID: PMC6617714 DOI: 10.1002/wrna.1526] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/05/2018] [Accepted: 01/14/2019] [Indexed: 12/21/2022]
Abstract
Alternative polyadenylation (APA) is how genes choose different sites for 3′ end formation for mRNAs during transcription. APA often occurs in a tissue‐ or developmental stage‐specific manner that can significantly affect gene activity by changing the protein product generated, the stability of the transcript, its localization within the cell, or its translatability. Despite the important regulatory effects that APA has on tissue‐specific gene expression, only a few examples have been characterized mechanistically. In this 2018 update to our 2010 review, we examine mechanisms for the control of APA and update our understanding of the older mechanisms since 2010. We once postulated the existence of tissue‐specific factors in APA. However, while a few tissue‐specific polyadenylation factors are known, the emerging conclusion is that the majority of APA is accomplished by altering levels of core polyadenylation proteins. Examples of those core proteins include CSTF2, CPSF1, and subunits of mammalian cleavage factor I. But despite support for these mechanisms, no one has yet documented any of these proteins changing in either a tissue‐specific or developmental manner. Given the profound effect that APA can have on gene expression and human health, improved understanding of tissue‐specific APA could lead to numerous advances in gene activity control. This article is categorized under:RNA Processing > 3′ End Processing RNA in Disease and Development > RNA in Development
Collapse
Affiliation(s)
- Clinton C MacDonald
- Department of Cell Biology & Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas
| |
Collapse
|
16
|
Belanger K, Nutter CA, Li J, Tasnim S, Liu P, Yu P, Kuyumcu-Martinez MN. CELF1 contributes to aberrant alternative splicing patterns in the type 1 diabetic heart. Biochem Biophys Res Commun 2018; 503:3205-3211. [PMID: 30158053 DOI: 10.1016/j.bbrc.2018.08.126] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 08/20/2018] [Indexed: 12/20/2022]
Abstract
Dysregulated alternative splicing (AS) that contributes to diabetes pathogenesis has been identified, but little is known about the RNA binding proteins (RBPs) involved. We have previously found that the RBP CELF1 is upregulated in the diabetic heart; however, it is unclear if CELF1 contributes to diabetes-induced AS changes. Utilizing genome wide approaches, we identified extensive changes in AS patterns in Type 1 diabetic (T1D) mouse hearts. We discovered that many aberrantly spliced genes in T1D hearts have CELF1 binding sites. CELF1-regulated AS affects key genes within signaling pathways relevant to diabetes pathogenesis. Disruption of CELF1 binding sites impairs AS regulation by CELF1. In sum, our results indicate that CELF1 target RNAs are aberrantly spliced in the T1D heart leading to abnormal gene expression. These discoveries pave the way for targeting RBPs and their RNA networks as novel therapies for cardiac complications of diabetes.
Collapse
Affiliation(s)
- KarryAnne Belanger
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Curtis A Nutter
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Jin Li
- Department of Electrical and Computer Engineering & TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Sadia Tasnim
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Peiru Liu
- Ball High School, Galveston, TX, 77555, USA
| | - Peng Yu
- Department of Electrical and Computer Engineering & TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Muge N Kuyumcu-Martinez
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA; Department of Neuroscience,Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, 77555, USA; Institute for Translational Sciences, University of Texas Medical Branch, Galveston, TX, 77555, USA.
| |
Collapse
|
17
|
Kim MJ, Choi SK, Hong SH, Eun JW, Nam SW, Han JW, You JS. Oncogenic IL7R is downregulated by histone deacetylase inhibitor in esophageal squamous cell carcinoma via modulation of acetylated FOXO1. Int J Oncol 2018; 53:395-403. [PMID: 29749437 DOI: 10.3892/ijo.2018.4392] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Accepted: 04/18/2018] [Indexed: 11/05/2022] Open
Abstract
The interleukin-7 receptor (IL7R) is generally expressed in immune cells and is critical in survival, development and homeostasis in the immune system. Advanced genome-wide cancer studies have reported that IL7R is genetically amplified in human esophageal squamous cell carcinoma (ESCC), however, the exact role of IL7R in ESCC has not been investigated. In the present study, it was found that IL7R was overexpressed in ESCC cohorts and the loss of IL7R induced anti-oncogenic effects in ESCC cell lines. A small panel of epigenetic drugs were screened for their ability to downregulate the expression of IL7R. Unexpectedly, apicidin, a histone deacetylase (HDAC) inhibitor, effectively downregulated the expression of IL7R in a dose-dependent manner at an early time-point, as determined by quantitative polymerase chain reaction and IL7R immunostaining, and did not require de novo protein synthesis. Of note, apicidin induced the acetylation of Forkhead box-containing protein, O subfamily 1, which acts as a repressor at the IL7R promoter, accompanied with depleted active histone modifications based on chromatin immunoprecipitation assay. Taken together, these results demonstrated that targeting oncogenic IL7R in ESCC by HDAC inhibitors may be a valuable therapeutic approach.
Collapse
Affiliation(s)
- Myoung Jun Kim
- Department of Biochemistry, Research Institute of Medical Science, School of Medicine, Konkuk University, Seoul 05029, Republic of Korea
| | - Sung Kyung Choi
- Department of Biochemistry, Research Institute of Medical Science, School of Medicine, Konkuk University, Seoul 05029, Republic of Korea
| | - Seong Hwi Hong
- Department of Biochemistry, Research Institute of Medical Science, School of Medicine, Konkuk University, Seoul 05029, Republic of Korea
| | - Jung Woo Eun
- Functional RNomics Research Center, College of Medicine, The Catholic University, Seoul 06591, Republic of Korea
| | - Suk Woo Nam
- Functional RNomics Research Center, College of Medicine, The Catholic University, Seoul 06591, Republic of Korea
| | - Jeung-Whan Han
- Research Center for Epigenome Regulation, School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jueng Soo You
- Department of Biochemistry, Research Institute of Medical Science, School of Medicine, Konkuk University, Seoul 05029, Republic of Korea
| |
Collapse
|
18
|
Taheri M, Sayad A. Investigating the exon 6 sequence changes of interleukin 7 receptor A (IL7RA) gene in patients with relapsing-remitting multiple sclerosis. Hum Antibodies 2018; 26:43-48. [PMID: 28582853 DOI: 10.3233/hab-170320] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
BACKGROUND Interleukin 7 receptor alpha (IL7RA) gene that encodes a subunit of IL7 receptor has been reported to be associated with different immunologic disease. OBJECTIVE Multiple Sclerosis (MS) patients have shown an aberrant blood level of soluble form of IL7R protein. The genomic changes in the sequence of this gene have been suggested to be correlated with its altered splicing specially, variants in the exon 6 of the gene have been reported to influence the maintenance or skipping of this exon and control the soluble or insoluble form of the final product. In order to evaluate this changes in the IL7RA gene and to determine a possible correlation between these changes and the MS susceptibility the whole sequence of the exon 6 and 7 and their flanking sequences were analyzed. METHODS In this regard, we investigate the sequence changes of the exon 6 and 7 of the IL7RA gene in 75 relapsing-remitting MS patients and compare the results with 75 healthy control using sequence analyzing. RESULTS The results of the sequence analysis were used in two aspects. The allelic and genotypic estimated frequencies of a reported risk variant rs6897932 in patients and controls in our population confirmed its association with the disease (P= 0.009, OR = 6.273, for TT genotype). Also, we report a possible hazardous cutoff for changes in a potential exon splicing silencer element (ESS (nt. 20-24)) and its correlation with rs6897932 to confer the risk of developing MS. CONCLUSION In conclusion our results confirm the association between IL7RA exon 6 sequence changes and increased susceptibility for multiple sclerosis.
Collapse
Affiliation(s)
- Mohammad Taheri
- Department of Medical Genetics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Urogenital Stem Cell Research Center, Shahid Labbafi Nejad Educational Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Arezou Sayad
- Department of Medical Genetics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
19
|
Margari L, Legrottaglie AR, Vincenti A, Coppola G, Operto FF, Buttiglione M, Cassano A, Bartolomeo N, Mariggiò MA. Association between SCN1A gene polymorphisms and drug resistant epilepsy in pediatric patients. Seizure 2018; 55:30-35. [PMID: 29353705 DOI: 10.1016/j.seizure.2018.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/29/2017] [Accepted: 01/02/2018] [Indexed: 12/16/2022] Open
Abstract
PURPOSE "Single Nucleotide Polymorphisms (SNPs)" could be an important explanation of drug resistance in epilepsy. The aim of this study was to investigate if genetic polymorphisms (SNPs) of the SCN1A gene could influence the response to anti - epileptic drugs (AED) and if they could predispose to a drug resistant epilepsy in pediatric patients. METHODS We investigated SNPs in exon and intronic regions of the SCN1A gene in a sample of 120 pediatric patients, in both drug-resistant and drug-responsive patients. Association between polymorphisms and refractory epilepsy were investigated by comparing SNPs in exon and intronic regions between the two groups. The genotypes of each intronic polymorphism in the drug-resistant group was analyzed. Odds ratios and confidence intervals were calculated. RESULTS None of the SNPs identified in exons of the SCN1A gene were associated with drug-resistance. In the intronic regions, a statistically significant difference was found in the prevalence of three polymorphisms was found between the two patient groups (rs6730344A/C, rs6732655A/T, rs10167228A/T). The analysis of the genotypes of each intronic polymorphism in the drug-resistant group revealed that the AA and AT genotypes for the rs1962842 polymorphism are associated with an increased risk of developing drug resistance compared to TT genotype. CONCLUSION The intronic rs6730344, rs6732655 and rs10167228 polymorphisms of the SCN1A gene are a potential risk factors for drug resistance. AA e AT genotype of the rs1962842 intronic polymorphism also emerged as a risk factor in the drug resistant group. Therefore, polymorphisms of the SCN1A gene could play a role in the response to AED in patients with drug-resistant epilepsy, with important implications for clinical practice.
Collapse
Affiliation(s)
- Lucia Margari
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Italy.
| | - Anna R Legrottaglie
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Italy
| | - Alessandra Vincenti
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Italy
| | - Giangennaro Coppola
- Child Neuropsychiatry Unit, Department of Medicine, Surgery and Dentistry, University of Salerno, Italy
| | - Francesca F Operto
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Italy
| | - Maura Buttiglione
- Child Neuropsychiatry Unit, Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Italy
| | - Amalia Cassano
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Italy
| | - Nicola Bartolomeo
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Italy
| | - Maria A Mariggiò
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Italy
| |
Collapse
|
20
|
Ramanouskaya TV, Grinev VV. The determinants of alternative RNA splicing in human cells. Mol Genet Genomics 2017; 292:1175-1195. [PMID: 28707092 DOI: 10.1007/s00438-017-1350-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 07/06/2017] [Indexed: 12/29/2022]
Abstract
Alternative splicing represents an important level of the regulation of gene function in eukaryotic organisms. It plays a critical role in virtually every biological process within an organism, including regulation of cell division and cell death, differentiation of tissues in the embryo and the adult organism, as well as in cellular response to diverse environmental factors. In turn, studies of the last decade have shown that alternative splicing itself is controlled by different mechanisms. Unfortunately, there is no clear understanding of how these diverse mechanisms, or determinants, regulate and constrain the set of alternative RNA species produced from any particular gene in every cell of the human body. Here, we provide a consolidated overview of alternative splicing determinants including RNA-protein interactions, epigenetic regulation via chromatin remodeling, coupling of transcription-to-alternative splicing, effect of secondary structures in pre-RNA, and function of the RNA quality control systems. We also extensively and critically discuss some mechanistic insights on coordinated inclusion/exclusion of exons during the formation of mature RNA molecules. We conclude that the final structure of RNA is pre-determined by a complex interplay between cis- and trans-acting factors. Altogether, currently available empirical data significantly expand our understanding of the functioning of the alternative splicing machinery of cells in normal and pathological conditions. On the other hand, there are still many blind spots that require further deep investigations.
Collapse
|
21
|
Catania F. From intronization to intron loss: How the interplay between mRNA-associated processes can shape the architecture and the expression of eukaryotic genes. Int J Biochem Cell Biol 2017; 91:136-144. [PMID: 28673893 DOI: 10.1016/j.biocel.2017.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/25/2017] [Accepted: 06/30/2017] [Indexed: 12/29/2022]
Abstract
Transcription-coupled processes such as capping, splicing, and cleavage/polyadenylation participate in the journey from genes to proteins. Although they are traditionally thought to serve only as steps in the generation of mature mRNAs, a synthesis of available data indicates that these processes could also act as a driving force for the evolution of eukaryotic genes. A theoretical framework for how mRNA-associated processes may shape gene structure and expression has recently been proposed. Factors that promote splicing and cleavage/polyadenylation in this framework compete for access to overlapping or neighboring signals throughout the transcription cycle. These antagonistic interactions allow mechanisms for intron gain and splice site recognition as well as common trends in eukaryotic gene structure and expression to be coherently integrated. Here, I extend this framework further. Observations that largely (but not exclusively) revolve around the formation of DNA-RNA hybrid structures, called R loops, and promoter directionality are integrated. Additionally, the interplay between splicing factors and cleavage/polyadenylation factors is theorized to also affect the formation of intragenic DNA double-stranded breaks thereby contributing to intron loss. The most notable prediction in this proposition is that RNA molecules can mediate intron loss by serving as a template to repair DNA double-stranded breaks. The framework presented here leverages a vast body of empirical observations, logically extending previous suggestions, and generating verifiable predictions to further substantiate the view that the intracellular environment plays an active role in shaping the structure and the expression of eukaryotic genes.
Collapse
Affiliation(s)
- Francesco Catania
- Institute for Evolution and Biodiversity, University of Münster, Hüfferstraße 1, 48149 Münster, Germany.
| |
Collapse
|
22
|
Exploring the Impact of Cleavage and Polyadenylation Factors on Pre-mRNA Splicing Across Eukaryotes. G3-GENES GENOMES GENETICS 2017; 7:2107-2114. [PMID: 28500052 PMCID: PMC5499120 DOI: 10.1534/g3.117.041483] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In human, mouse, and Drosophila, the spliceosomal complex U1 snRNP (U1) protects transcripts from premature cleavage and polyadenylation at proximal intronic polyadenylation signals (PAS). These U1-mediated effects preserve transcription integrity, and are known as telescripting. The watchtower role of U1 throughout transcription is clear. What is less clear is whether cleavage and polyadenylation factors (CPFs) are simply patrolled or if they might actively antagonize U1 recruitment. In addressing this question, we found that, in the introns of human, mouse, and Drosophila, and of 14 other eukaryotes, including multi- and single-celled species, the conserved AATAAA PAS—a major target for CPFs—is selected against. This selective pressure, approximated using DNA strand asymmetry, is detected for peripheral and internal introns alike. Surprisingly, it is more pronounced within—rather than outside—the action range of telescripting, and particularly intense in the vicinity of weak 5′ splice sites. Our study uncovers a novel feature of eukaryotic genes: that the AATAAA PAS is universally counter-selected in spliceosomal introns. This pattern implies that CPFs may attempt to access introns at any time during transcription. However, natural selection operates to minimize this access. By corroborating and extending previous work, our study further indicates that CPF access to intronic PASs might perturb the recruitment of U1 to the adjacent 5′ splice sites. These results open the possibility that CPFs may impact the splicing process across eukaryotes.
Collapse
|
23
|
Neve J, Patel R, Wang Z, Louey A, Furger AM. Cleavage and polyadenylation: Ending the message expands gene regulation. RNA Biol 2017; 14:865-890. [PMID: 28453393 PMCID: PMC5546720 DOI: 10.1080/15476286.2017.1306171] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/02/2017] [Accepted: 03/09/2017] [Indexed: 12/13/2022] Open
Abstract
Cleavage and polyadenylation (pA) is a fundamental step that is required for the maturation of primary protein encoding transcripts into functional mRNAs that can be exported from the nucleus and translated in the cytoplasm. 3'end processing is dependent on the assembly of a multiprotein processing complex on the pA signals that reside in the pre-mRNAs. Most eukaryotic genes have multiple pA signals, resulting in alternative cleavage and polyadenylation (APA), a widespread phenomenon that is important to establish cell state and cell type specific transcriptomes. Here, we review how pA sites are recognized and comprehensively summarize how APA is regulated and creates mRNA isoform profiles that are characteristic for cell types, tissues, cellular states and disease.
Collapse
Affiliation(s)
- Jonathan Neve
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Radhika Patel
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Zhiqiao Wang
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Alastair Louey
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | | |
Collapse
|
24
|
Galarza-Muñoz G, Briggs FBS, Evsyukova I, Schott-Lerner G, Kennedy EM, Nyanhete T, Wang L, Bergamaschi L, Widen SG, Tomaras GD, Ko DC, Bradrick SS, Barcellos LF, Gregory SG, Garcia-Blanco MA. Human Epistatic Interaction Controls IL7R Splicing and Increases Multiple Sclerosis Risk. Cell 2017; 169:72-84.e13. [PMID: 28340352 DOI: 10.1016/j.cell.2017.03.007] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 09/18/2016] [Accepted: 03/02/2017] [Indexed: 12/18/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune disorder where T cells attack neurons in the central nervous system (CNS) leading to demyelination and neurological deficits. A driver of increased MS risk is the soluble form of the interleukin-7 receptor alpha chain gene (sIL7R) produced by alternative splicing of IL7R exon 6. Here, we identified the RNA helicase DDX39B as a potent activator of this exon and consequently a repressor of sIL7R, and we found strong genetic association of DDX39B with MS risk. Indeed, we showed that a genetic variant in the 5' UTR of DDX39B reduces translation of DDX39B mRNAs and increases MS risk. Importantly, this DDX39B variant showed strong genetic and functional epistasis with allelic variants in IL7R exon 6. This study establishes the occurrence of biological epistasis in humans and provides mechanistic insight into the regulation of IL7R exon 6 splicing and its impact on MS risk.
Collapse
Affiliation(s)
- Gaddiel Galarza-Muñoz
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Center for RNA Biology, Duke University, Durham, NC 27710, USA; Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Farren B S Briggs
- Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Irina Evsyukova
- Center for RNA Biology, Duke University, Durham, NC 27710, USA
| | - Geraldine Schott-Lerner
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Edward M Kennedy
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Tinashe Nyanhete
- Department of Immunology, Duke University Durham, NC 27710, USA; Department of Surgery, Duke University Durham, NC 27710, USA
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Laura Bergamaschi
- Duke Molecular Physiology Institute, Duke University, Durham, NC 27701, USA
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Georgia D Tomaras
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Department of Immunology, Duke University Durham, NC 27710, USA; Department of Surgery, Duke University Durham, NC 27710, USA
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Department of Medicine, Duke University Medical Center; Durham, NC 27710, USA
| | - Shelton S Bradrick
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Center for RNA Biology, Duke University, Durham, NC 27710, USA; Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Lisa F Barcellos
- Division of Epidemiology, School of Public Health, University of California Berkeley, Berkeley, CA 94720, USA
| | - Simon G Gregory
- Duke Molecular Physiology Institute, Duke University, Durham, NC 27701, USA; Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA.
| | - Mariano A Garcia-Blanco
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Center for RNA Biology, Duke University, Durham, NC 27710, USA; Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| |
Collapse
|
25
|
Interconnections Between RNA-Processing Pathways Revealed by a Sequencing-Based Genetic Screen for Pre-mRNA Splicing Mutants in Fission Yeast. G3-GENES GENOMES GENETICS 2016; 6:1513-23. [PMID: 27172183 PMCID: PMC4889648 DOI: 10.1534/g3.116.027508] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pre-mRNA splicing is an essential component of eukaryotic gene expression and is highly conserved from unicellular yeasts to humans. Here, we present the development and implementation of a sequencing-based reverse genetic screen designed to identify nonessential genes that impact pre-mRNA splicing in the fission yeast Schizosaccharomyces pombe, an organism that shares many of the complex features of splicing in higher eukaryotes. Using a custom-designed barcoding scheme, we simultaneously queried ∼3000 mutant strains for their impact on the splicing efficiency of two endogenous pre-mRNAs. A total of 61 nonessential genes were identified whose deletions resulted in defects in pre-mRNA splicing; enriched among these were factors encoding known or predicted components of the spliceosome. Included among the candidates identified here are genes with well-characterized roles in other RNA-processing pathways, including heterochromatic silencing and 3ʹ end processing. Splicing-sensitive microarrays confirm broad splicing defects for many of these factors, revealing novel functional connections between these pathways.
Collapse
|
26
|
Leigh-Brown S, Goncalves A, Thybert D, Stefflova K, Watt S, Flicek P, Brazma A, Marioni JC, Odom DT. Regulatory Divergence of Transcript Isoforms in a Mammalian Model System. PLoS One 2015; 10:e0137367. [PMID: 26339903 PMCID: PMC4560434 DOI: 10.1371/journal.pone.0137367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/15/2015] [Indexed: 11/24/2022] Open
Abstract
Phenotypic differences between species are driven by changes in gene expression and, by extension, by modifications in the regulation of the transcriptome. Investigation of mammalian transcriptome divergence has been restricted to analysis of bulk gene expression levels and gene-internal splicing. Using allele-specific expression analysis in inter-strain hybrids of Mus musculus, we determined the contribution of multiple cellular regulatory systems to transcriptome divergence, including: alternative promoter usage, transcription start site selection, cassette exon usage, alternative last exon usage, and alternative polyadenylation site choice. Between mouse strains, a fifth of genes have variations in isoform usage that contribute to transcriptomic changes, half of which alter encoded amino acid sequence. Virtually all divergence in isoform usage altered the post-transcriptional regulatory instructions in gene UTRs. Furthermore, most genes with isoform differences between strains contain changes originating from multiple regulatory systems. This result indicates widespread cross-talk and coordination exists among different regulatory systems. Overall, isoform usage diverges in parallel with and independently to gene expression evolution, and the cis and trans regulatory contribution to each differs significantly.
Collapse
Affiliation(s)
- Sarah Leigh-Brown
- University of Cambridge, Cancer Research UK - Cambridge Institute, Li Ka Shing Centre, Cambridge, United Kingdom
| | - Angela Goncalves
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - David Thybert
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Klara Stefflova
- California Institute of Technology, Division of Biology, Pasadena, California, United States of America
| | - Stephen Watt
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Paul Flicek
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Alvis Brazma
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - John C. Marioni
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Duncan T. Odom
- University of Cambridge, Cancer Research UK - Cambridge Institute, Li Ka Shing Centre, Cambridge, United Kingdom
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| |
Collapse
|
27
|
Churchman SM, El-Jawhari JJ, Burska AN, Parmar R, Goëb V, Conaghan PG, Emery P, Ponchel F. Modulation of peripheral T-cell function by interleukin-7 in rheumatoid arthritis. Arthritis Res Ther 2014; 16:511. [PMID: 25533722 PMCID: PMC4298067 DOI: 10.1186/s13075-014-0511-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 12/11/2014] [Indexed: 01/26/2023] Open
Abstract
Introduction Interleukin-7 (IL-7) is a cytokine essential for T-cell lymphopoiesis, survival and polarization with an emerging role in autoimmunity. We previously demonstrated reduced levels of circulating IL-7 in rheumatoid arthritis (RA), although high amounts are expressed in joints, suggesting differences between systemic and synovial effects. We observed healthy levels of IL-7 in 48% of RA patients in clinical remission (CR) and aimed to investigate the consequences of IL-7 deficiency on T-cell responses. Methods We used RA patients with active disease and in CR presenting various levels of IL-7, to investigate its modulatory effects on T cells by analysing responses to phyto-haemagglutinin (PHA), expression of polarization or survival factors, or suppression by regulatory T cells (Tregs). Results IL-7 levels were normal (>10 pg/ml) in 48% of RA patients in CR. Amongst 63 CR patients followed up for 18 months, lack of IL-7 recovery was observed in 13 out of 15 (86%) patients experiencing relapse but only 11 out of 48 (23%) of those who did not (P = 0.0002). Binary regressions showed high significance for below normal IL-7 levels for self-reported maternal family history of arthritis (odds ratio (OR): 7.66, P = 0.006) and a trend for smoking (OR: 3.33, P = 0.068) with no further demographic or clinical associations. Serum IL-7 correlated with restored CD4+T-cell response to PHA (rho = 0.879); this was not related to an increase in T-cell proliferation capacity or expression of survival factors B-cell lymphoma 2 (BCL2) and BCL2-associated protein X (BAX). Expression of Th1 polarization factor (TBET) was also dependent on exposure to IL-7 in vivo (rho = 0.600). In contrast CD25highTregs’ response to PHA was not affected by in vivo IL-7, but their suppression capabilities were related to circulating IL-7 (rho = 0.589). Co-stimulation with IL-7 (mimicking the joint environment) increased responsiveness of CD4+T-cells to PHA, lowering the ability of CD25highTregs to suppress them. Conclusions Our data demonstrate that IL-7 has a critical role in modulating T-cell function in vivo, possibly explaining opposing effects observed systemically and in the joint. Lack of IL-7 recovery in CR by maintaining a suppressed immune system may be a determinant factor in the occurrence of relapse. Electronic supplementary material The online version of this article (doi:10.1186/s13075-014-0511-3) contains supplementary material, which is available to authorized users.
Collapse
|
28
|
Romeo MJ, Agrawal R, Pomés A, Woodfolk JA. A molecular perspective on TH2-promoting cytokine receptors in patients with allergic disease. J Allergy Clin Immunol 2013; 133:952-60. [PMID: 24084078 DOI: 10.1016/j.jaci.2013.08.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 08/12/2013] [Accepted: 08/13/2013] [Indexed: 12/17/2022]
Abstract
The cytokines IL-4, IL-13, and thymic stromal lymphopoietin play a key role in allergic disease by virtue of their ability to initiate, maintain, and augment TH2 responses. These molecules mediate their effects through type 1 cytokine receptors, which bind cytokines with a characteristic structure. Receptors are expressed on a broad array of immune cell types and are integral to complex cytokine networks operating in health and disease. TH2-promoting cytokines bind different configurations of receptors. Receptor subunits can exist in surface-bound or soluble forms, as well as in isolation or in partnership with other subunits. Sharing of receptor subunits among different cytokine receptor complexes adds to the intricate landscape. This article describes the characteristics of receptors for IL-4, IL-13, and thymic stromal lymphopoietin and their respective ligands from a structure-function perspective. We detail the mechanisms of receptor complex assembly, the interrelated nature of these receptors, and the effect on allergic inflammation. The ability for novel and atypical types of receptors to modulate inflammatory processes is also discussed. We highlight current and emerging treatments that target TH2-promoting receptor complexes. Understanding the molecular features of these receptors provides insight into different disease phenotypes and the variable clinical outcomes arising from targeted therapies. These considerations can be used to inform future directions for research and creative strategies for treating individual patients.
Collapse
Affiliation(s)
- Martin J Romeo
- Asthma and Allergic Diseases Center, University of Virginia, Charlottesville, Va
| | - Rachana Agrawal
- Asthma and Allergic Diseases Center, University of Virginia, Charlottesville, Va
| | - Anna Pomés
- Indoor Biotechnologies Inc, Charlottesville, Va
| | - Judith A Woodfolk
- Asthma and Allergic Diseases Center, University of Virginia, Charlottesville, Va.
| |
Collapse
|
29
|
Abstract
Precursor mRNA splicing is one of the most highly regulated processes in metazoan species. In addition to generating vast repertoires of RNAs and proteins, splicing has a profound impact on other gene regulatory layers, including mRNA transcription, turnover, transport, and translation. Conversely, factors regulating chromatin and transcription complexes impact the splicing process. This extensive crosstalk between gene regulatory layers takes advantage of dynamic spatial, physical, and temporal organizational properties of the cell nucleus, and further emphasizes the importance of developing a multidimensional understanding of splicing control.
Collapse
|
30
|
Catania F, Lynch M. A simple model to explain evolutionary trends of eukaryotic gene architecture and expression: how competition between splicing and cleavage/polyadenylation factors may affect gene expression and splice-site recognition in eukaryotes. Bioessays 2013; 35:561-70. [PMID: 23568225 DOI: 10.1002/bies.201200127] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Enormous phylogenetic variation exists in the number and sizes of introns in protein-coding genes. Although some consideration has been given to the underlying role of the population-genetic environment in defining such patterns, the influence of the intracellular environment remains virtually unexplored. Drawing from observations on interactions between co-transcriptional processes involved in splicing and mRNA 3'-end formation, a mechanistic model is proposed for splice-site recognition that challenges the commonly accepted intron- and exon-definition models. Under the suggested model, splicing factors that outcompete 3'-end processing factors for access to intronic binding sites concurrently favor the recruitment of 3'-end processing factors at the pre-mRNA tail. This hypothesis sheds new light on observations such as the intron-mediated enhancement of gene expression and the negative correlation between intron length and levels of gene expression.
Collapse
Affiliation(s)
- Francesco Catania
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany.
| | | |
Collapse
|
31
|
Rehfeld A, Plass M, Krogh A, Friis-Hansen L. Alterations in polyadenylation and its implications for endocrine disease. Front Endocrinol (Lausanne) 2013; 4:53. [PMID: 23658553 PMCID: PMC3647115 DOI: 10.3389/fendo.2013.00053] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 04/22/2013] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Polyadenylation is the process in which the pre-mRNA is cleaved at the poly(A) site and a poly(A) tail is added - a process necessary for normal mRNA formation. Genes with multiple poly(A) sites can undergo alternative polyadenylation (APA), producing distinct mRNA isoforms with different 3' untranslated regions (3' UTRs) and in some cases different coding regions. Two thirds of all human genes undergo APA. The efficiency of the polyadenylation process regulates gene expression and APA plays an important part in post-transcriptional regulation, as the 3' UTR contains various cis-elements associated with post-transcriptional regulation, such as target sites for micro-RNAs and RNA-binding proteins. Implications of alterations in polyadenylation for endocrine disease: Alterations in polyadenylation have been found to be causative of neonatal diabetes and IPEX (immune dysfunction, polyendocrinopathy, enteropathy, X-linked) and to be associated with type I and II diabetes, pre-eclampsia, fragile X-associated premature ovarian insufficiency, ectopic Cushing syndrome, and many cancer diseases, including several types of endocrine tumor diseases. PERSPECTIVES Recent developments in high-throughput sequencing have made it possible to characterize polyadenylation genome-wide. Antisense elements inhibiting or enhancing specific poly(A) site usage can induce desired alterations in polyadenylation, and thus hold the promise of new therapeutic approaches. SUMMARY This review gives a detailed description of alterations in polyadenylation in endocrine disease, an overview of the current literature on polyadenylation and summarizes the clinical implications of the current state of research in this field.
Collapse
Affiliation(s)
- Anders Rehfeld
- Genomic Medicine, Rigshospitalet, Copenhagen University HospitalCopenhagen, Denmark
| | - Mireya Plass
- Department of Biology, The Bioinformatics Centre, University of CopenhagenCopenhagen, Denmark
| | - Anders Krogh
- Department of Biology, The Bioinformatics Centre, University of CopenhagenCopenhagen, Denmark
| | - Lennart Friis-Hansen
- Genomic Medicine, Rigshospitalet, Copenhagen University HospitalCopenhagen, Denmark
- *Correspondence: Lennart Friis-Hansen, Genomic Medicine, Rigshospitalet, Copenhagen University Hospital, 4113, Blegdamsvej 9, DK2100 Copenhagen, Denmark. e-mail:
| |
Collapse
|