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Yuan N, Shen L, Peng Q, Sha R, Wang Z, Xie Z, You X, Feng Y. SRSF1 Is Required for Mitochondrial Homeostasis and Thermogenic Function in Brown Adipocytes Through its Control of Ndufs3 Splicing. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306871. [PMID: 38569495 PMCID: PMC11151030 DOI: 10.1002/advs.202306871] [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: 09/19/2023] [Revised: 02/04/2024] [Indexed: 04/05/2024]
Abstract
RNA splicing dysregulation and the involvement of specific splicing factors are emerging as common factors in both obesity and metabolic disorders. The study provides compelling evidence that the absence of the splicing factor SRSF1 in mature adipocytes results in whitening of brown adipocyte tissue (BAT) and impaired thermogenesis, along with the inhibition of white adipose tissue browning in mice. Combining single-nucleus RNA sequencing with transmission electron microscopy, it is observed that the transformation of BAT cell types is associated with dysfunctional mitochondria, and SRSF1 deficiency leads to degenerated and fragmented mitochondria within BAT. The results demonstrate that SRSF1 effectively binds to constitutive exon 6 of Ndufs3 pre-mRNA and promotes its inclusion. Conversely, the deficiency of SRSF1 results in impaired splicing of Ndufs3, leading to reduced levels of functional proteins that are essential for mitochondrial complex I assembly and activity. Consequently, this deficiency disrupts mitochondrial integrity, ultimately compromising the thermogenic capacity of BAT. These findings illuminate a novel role for SRSF1 in influencing mitochondrial function and BAT thermogenesis through its regulation of Ndufs3 splicing within BAT.
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Affiliation(s)
- Ningyang Yuan
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
- Lin He's Academician Workstation of New Medicine and Clinical Translation in Jining Medical UniversityJining Medical UniversityJining272067China
| | - Lei Shen
- Department of General SurgeryZhongshan HospitalFudan UniversityShanghai200032China
| | - Qian Peng
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
| | - Rula Sha
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
| | - Zhenzhen Wang
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
| | - Zhiqi Xie
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
| | - Xue You
- Lin He's Academician Workstation of New Medicine and Clinical Translation in Jining Medical UniversityJining Medical UniversityJining272067China
| | - Ying Feng
- CAS Key Laboratory of Nutrition, Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200031China
- Lin He's Academician Workstation of New Medicine and Clinical Translation in Jining Medical UniversityJining Medical UniversityJining272067China
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Liu F, Cai S, Dai L, Ai N, Feng G, Wang N, Zhang W, Liu K, Zhou B. SR45a plays a key role in enhancing cotton resistance to Verticillium dahliae by alternative splicing of immunity genes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 38569053 DOI: 10.1111/tpj.16750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/22/2024] [Accepted: 03/20/2024] [Indexed: 04/05/2024]
Abstract
Alternative splicing (AS) of pre-mRNAs increases the diversity of transcriptome and proteome and plays fundamental roles in plant development and stress responses. However, the prevalent changes in AS events and the regulating mechanisms of plants in response to pathogens remain largely unknown. Here, we show that AS changes are an important mechanism conferring cotton immunity to Verticillium dahliae (Vd). GauSR45a, encoding a serine/arginine-rich RNA binding protein, was upregulated expression and underwent AS in response to Vd infection in Gossypium australe, a wild diploid cotton species highly resistant to Vd. Silencing GauSR45a substantially reduced the splicing ratio of Vd-induced immune-associated genes, including GauBAK1 (BRI1-associated kinase 1) and GauCERK1 (chitin elicitor receptor kinase 1). GauSR45a binds to the GAAGA motif that is commonly found in the pre-mRNA of genes essential for PTI, ETI, and defense. The binding between GauSR45a and the GAAGA motif in the pre-mRNA of BAK1 was enhanced by two splicing factors of GauU2AF35B and GauU1-70 K, thereby facilitating exon splicing; silencing either AtU2AF35B or AtU1-70 K decreased the resistance to Vd in transgenic GauSR45a Arabidopsis. Overexpressing the short splicing variant of BAK1GauBAK1.1 resulted in enhanced Verticillium wilt resistance rather than the long one GauBAK1.2. Vd-induced far more AS events were in G. barbadense (resistant tetraploid cotton) than those in G. hirsutum (susceptible tetraploid cotton) during Vd infection, indicating resistance divergence in immune responses at a genome-wide scale. We provided evidence showing a fundamental mechanism by which GauSR45a enhances cotton resistance to Vd through global regulation of AS of immunity genes.
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Affiliation(s)
- Fujie Liu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
- Institue of Crop Germplasm and Biotechnology/Jiangsu Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Zhongling Street 50#, Nanjing, 210014, China
| | - Sheng Cai
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
- Nanjing Forestry University, 159 Longpan Road, Nanjing, 210095, Jiangsu, People's Republic of China
| | - Lingjun Dai
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
| | - Nijiang Ai
- Xinjiang Production and Construction Corps, Shihezi Agricultural Science Research Institute, Shihezi, 832000, Xinjiang, People's Republic of China
| | - Guoli Feng
- Xinjiang Production and Construction Corps, Shihezi Agricultural Science Research Institute, Shihezi, 832000, Xinjiang, People's Republic of China
| | - Ningshan Wang
- Xinjiang Production and Construction Corps, Shihezi Agricultural Science Research Institute, Shihezi, 832000, Xinjiang, People's Republic of China
| | - Wenli Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
| | - Kang Liu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
| | - Baoliang Zhou
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production cosponsored by Jiangsu Province and Ministry of Education, Cotton Germplasm Enhancement and Application Engineering Research Center (Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People's Republic of China
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Malakar P, Shukla S, Mondal M, Kar RK, Siddiqui JA. The nexus of long noncoding RNAs, splicing factors, alternative splicing and their modulations. RNA Biol 2024; 21:1-20. [PMID: 38017665 PMCID: PMC10761143 DOI: 10.1080/15476286.2023.2286099] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2023] [Indexed: 11/30/2023] Open
Abstract
The process of alternative splicing (AS) is widely deregulated in a variety of cancers. Splicing is dependent upon splicing factors. Recently, several long noncoding RNAs (lncRNAs) have been shown to regulate AS by directly/indirectly interacting with splicing factors. This review focuses on the regulation of AS by lncRNAs through their interaction with splicing factors. AS mis-regulation caused by either mutation in splicing factors or deregulated expression of splicing factors and lncRNAs has been shown to be involved in cancer development and progression, making aberrant splicing, splicing factors and lncRNA suitable targets for cancer therapy. This review also addresses some of the current approaches used to target AS, splicing factors and lncRNAs. Finally, we discuss research challenges, some of the unanswered questions in the field and provide recommendations to advance understanding of the nexus of lncRNAs, AS and splicing factors in cancer.
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Affiliation(s)
- Pushkar Malakar
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational Research Institute (RKMVERI), Kolkata, India
| | - Sudhanshu Shukla
- Department of Biosciences and Bioengineering, Indian Institute of Technology Dharwad, Dharwad, Karnataka, India
| | - Meghna Mondal
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational Research Institute (RKMVERI), Kolkata, India
| | - Rajesh Kumar Kar
- Department of Neurosurgery, School of Medicine, Yale University, New Haven, CT, USA
| | - Jawed Akhtar Siddiqui
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
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Yang Y, Abbas S, Sayem MA, Dutta A, Mohi G. SRSF2 mutation reduces polycythemia and impairs hematopoietic progenitor functions in JAK2V617F-driven myeloproliferative neoplasm. Blood Cancer J 2023; 13:171. [PMID: 38012156 PMCID: PMC10682023 DOI: 10.1038/s41408-023-00947-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: 09/06/2023] [Revised: 11/01/2023] [Accepted: 11/09/2023] [Indexed: 11/29/2023] Open
Abstract
SRSF2 mutations are found in association with JAK2V617F in myeloproliferative neoplasms (MPN), most frequently in myelofibrosis (MF). However, the contribution of SRSF2 mutation in JAK2V617F-driven MPN remains elusive. To investigate the consequences of SRSF2P95H and JAK2V617F mutations in MPN, we generated Cre-inducible Srsf2P95H/+Jak2V617F/+ knock-in mice. We show that co-expression of Srsf2P95H mutant reduced red blood cell, neutrophil, and platelet counts, attenuated splenomegaly but did not induce bone marrow fibrosis in Jak2V617F/+ mice. Furthermore, co-expression of Srsf2P95H diminished the competitiveness of Jak2V617F mutant hematopoietic stem/progenitor cells. We found that Srsf2P95H mutant reduced the TGF-β levels but increased the expression of S100A8 and S100A9 in Jak2V617F/+ mice. Furthermore, enforced expression of S100A9 in Jak2V617F/+ mice bone marrow significantly reduced the red blood cell, hemoglobin, and hematocrit levels. Overall, these data suggest that concurrent expression of Srsf2P95H and Jak2V617F mutants reduces erythropoiesis but does not promote the development of bone marrow fibrosis in mice.
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Affiliation(s)
- Yue Yang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Salar Abbas
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Mohammad A Sayem
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Avik Dutta
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Golam Mohi
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA.
- University of Virginia Cancer Center, Charlottesville, VA, 22908, USA.
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5
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Li Z, He Z, Wang J, Kong G. RNA splicing factors in normal hematopoiesis and hematologic malignancies: novel therapeutic targets and strategies. J Leukoc Biol 2023; 113:149-163. [PMID: 36822179 DOI: 10.1093/jleuko/qiac015] [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: 08/09/2022] [Indexed: 01/18/2023] Open
Abstract
RNA splicing, a crucial transesterification-based process by which noncoding regions are removed from premature RNA to create mature mRNA, regulates various cellular functions, such as proliferation, survival, and differentiation. Clinical and functional studies over the past 10 y have confirmed that mutations in RNA splicing factors are among the most recurrent genetic abnormalities in hematologic neoplasms, including myeloid malignancies, chronic lymphocytic leukemia, mantle cell lymphoma, and clonal hematopoiesis. These findings indicate an important role for splicing factor mutations in the development of clonal hematopoietic disorders. Mutations in core or accessory components of the RNA spliceosome complex alter splicing sites in a manner of change of function. These changes can result in the dysregulation of cancer-associated gene expression and the generation of novel mRNA transcripts, some of which are not only critical to disease development but may be also serving as potential therapeutic targets. Furthermore, multiple studies have revealed that hematopoietic cells bearing mutations in splicing factors depend on the expression of the residual wild-type allele for survival, and these cells are more sensitive to reduced expression of wild-type splicing factors or chemical perturbations of the splicing machinery. These findings suggest a promising possibility for developing novel therapeutic opportunities in tumor cells based on mutations in splicing factors. Here, we combine current knowledge of the mechanistic and functional effects of frequently mutated splicing factors in normal hematopoiesis and the effects of their mutations in hematologic malignancies. Moreover, we discuss the development of potential therapeutic opportunities based on these mutations.
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Affiliation(s)
- Zhenzhen Li
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, No. 127 Youyi West Road, Beilin District, Xi'an, Shaanxi 710072, China
| | - Zhongzheng He
- Department of Neurosurgery, Mini-invasive Neurosurgery and Translational Medical Center, Xi'an Central Hospital, Xi'an Jiaotong University, No. 161 Xiwu Road, Xincheng District, Xi'an, Shaanxi 710003, China
| | - Jihan Wang
- Xi'an Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Medical Research, Northwestern Polytechnical University, No. 127 Youyi West Road, Beilin District, Xi'an, Shaanxi 710072, China
| | - Guangyao Kong
- National & Local Joint Engineering Research Center of Biodiagnosis and Biotherapy, The Second Affiliated Hospital of Xi'an Jiaotong University, No. 157 Xiwu Road, Xincheng District, Xi'an, Shaanxi 710004, China
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6
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Vester K, Preußner M, Holton N, Feng S, Schultz C, Heyd F, Wahl MC. Recruitment of a splicing factor to the nuclear lamina for its inactivation. Commun Biol 2022; 5:736. [PMID: 35869234 PMCID: PMC9307855 DOI: 10.1038/s42003-022-03689-y] [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: 01/09/2022] [Accepted: 07/08/2022] [Indexed: 11/10/2022] Open
Abstract
Precursor messenger RNA splicing is a highly regulated process, mediated by a complex RNA-protein machinery, the spliceosome, that encompasses several hundred proteins and five small nuclear RNAs in humans. Emerging evidence suggests that the spatial organization of splicing factors and their spatio-temporal dynamics participate in the regulation of splicing. So far, methods to manipulate the spatial distribution of splicing factors in a temporally defined manner in living cells are missing. Here, we describe such an approach that takes advantage of a reversible chemical dimerizer, and outline the requirements for efficient, reversible re-localization of splicing factors to selected sub-nuclear compartments. In a proof-of-principle study, the partial re-localization of the PRPF38A protein to the nuclear lamina in HEK293T cells induced a moderate increase in intron retention. Our approach allows fast and reversible re-localization of splicing factors, has few side effects and can be applied to many splicing factors by fusion of a protein tag through genome engineering. Apart from the systematic analysis of the spatio-temporal aspects of splicing regulation, the approach has a large potential for the fast induction and reversal of splicing switches and can reveal mechanisms of splicing regulation in native nuclear environments. Through the use of a reversible chemical dimerizer, the splicing factor PRPF38A is re-localized to the nuclear lamina, paving the way for a systematic analysis of spatio-temporal splicing regulation.
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7
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Su S, Katopodi XL, Pita-Juarez YH, Maverakis E, Vlachos IS, Adamopoulos IE. Serine and arginine rich splicing factor 1 deficiency alters pathways involved in IL-17A expression and is implicated in human psoriasis. Clin Immunol 2022; 240:109041. [PMID: 35613697 PMCID: PMC10797199 DOI: 10.1016/j.clim.2022.109041] [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: 03/31/2022] [Revised: 05/08/2022] [Accepted: 05/09/2022] [Indexed: 12/25/2022]
Abstract
Serine and Arginine Rich Splicing Factor 1 (SRSF1) is a splicing factor that binds to exonic enhancers and stimulates splicing and is previously implicated with autoimmunity. Herein, we investigate the role of SRSF1 in regulating innate immune functions that are pertinent in the pathogenesis of auto-inflammatory diseases. Specifically, we show that conditional deletion of SRSF1 in mature lymphocytes resulted in higher expression of il-17a and il-17 f and an expansion of IL17A+ CD8 T cells. Mechanistically, the aberrant expression of IL-17A in SRSF1 cKO mice could not be attributed to alternative splicing of il-17a or il-17 f genes but possibly to defective CD11B+LY6C+ myeloid derived suppressor function in the spleen. Finally, meta-analysis of RNA-Seq collected from psoriasis patients demonstrate a clear correlation between SRSF1 and psoriasis that suggests a putative role of SRSF1 in IL-17A-induced psoriasis.
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Affiliation(s)
- Shi Su
- Department of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Xanthi-Lida Katopodi
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Yered H Pita-Juarez
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Emanual Maverakis
- Department of Dermatology, University of California, Davis, Sacramento, CA, USA
| | - Ioannis S Vlachos
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; Harvard Medical School Initiative for RNA Medicine, Boston, MA, USA; Cancer Research Institute, Beth Israel Deaconess Medical Center, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Iannis E Adamopoulos
- Department of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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Stanley RF, Abdel-Wahab O. Dysregulation and therapeutic targeting of RNA splicing in cancer. NATURE CANCER 2022; 3:536-546. [PMID: 35624337 PMCID: PMC9551392 DOI: 10.1038/s43018-022-00384-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 04/22/2022] [Indexed: 05/15/2023]
Abstract
High-throughput sequencing and functional characterization of the cancer transcriptome have uncovered cancer-specific dysregulation of RNA splicing across a variety of cancers. Alterations in the cancer genome and dysregulation of RNA splicing factors lead to missplicing, splicing alteration-dependent gene expression and, in some cases, generation of novel splicing-derived proteins. Here, we review recent advances in our understanding of aberrant splicing in cancer pathogenesis and present strategies to harness cancer-specific aberrant splicing for therapeutic intent.
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Affiliation(s)
- Robert F Stanley
- Human Oncology and Pathogenesis Program and Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program and Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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9
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RBBP6 activates the pre-mRNA 3' end processing machinery in humans. Genes Dev 2022; 36:210-224. [PMID: 35177536 PMCID: PMC8887125 DOI: 10.1101/gad.349223.121] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/01/2022] [Indexed: 11/25/2022]
Abstract
In this study, Boreikaite et al. reconstituted specific and efficient 3′ endonuclease activity of human CPSF with purified proteins. This required the seven-subunit CPSF as well as three additional protein factors: cleavage stimulatory factor (CStF), cleavage factor IIm (CFIIm), and, importantly, the multidomain protein RBBP6. 3′ end processing of most human mRNAs is carried out by the cleavage and polyadenylation specificity factor (CPSF; CPF in yeast). Endonucleolytic cleavage of the nascent pre-mRNA defines the 3′ end of the mature transcript, which is important for mRNA localization, translation, and stability. Cleavage must therefore be tightly regulated. Here, we reconstituted specific and efficient 3′ endonuclease activity of human CPSF with purified proteins. This required the seven-subunit CPSF as well as three additional protein factors: cleavage stimulatory factor (CStF), cleavage factor IIm (CFIIm), and, importantly, the multidomain protein RBBP6. Unlike its yeast homolog Mpe1, which is a stable subunit of CPF, RBBP6 does not copurify with CPSF and is recruited in an RNA-dependent manner. Sequence and mutational analyses suggest that RBBP6 interacts with the WDR33 and CPSF73 subunits of CPSF. Thus, it is likely that the role of RBBP6 is conserved from yeast to humans. Overall, our data are consistent with CPSF endonuclease activation and site-specific pre-mRNA cleavage being highly controlled to maintain fidelity in mRNA processing.
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10
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Jobbins AM, Campagne S, Weinmeister R, Lucas CM, Gosliga AR, Clery A, Chen L, Eperon LP, Hodson MJ, Hudson AJ, Allain FHT, Eperon IC. Exon-independent recruitment of SRSF1 is mediated by U1 snRNP stem-loop 3. EMBO J 2022; 41:e107640. [PMID: 34779515 PMCID: PMC8724738 DOI: 10.15252/embj.2021107640] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 12/11/2022] Open
Abstract
SRSF1 protein and U1 snRNPs are closely connected splicing factors. They both stimulate exon inclusion, SRSF1 by binding to exonic splicing enhancer sequences (ESEs) and U1 snRNPs by binding to the downstream 5' splice site (SS), and both factors affect 5' SS selection. The binding of U1 snRNPs initiates spliceosome assembly, but SR proteins such as SRSF1 can in some cases substitute for it. The mechanistic basis of this relationship is poorly understood. We show here by single-molecule methods that a single molecule of SRSF1 can be recruited by a U1 snRNP. This reaction is independent of exon sequences and separate from the U1-independent process of binding to an ESE. Structural analysis and cross-linking data show that SRSF1 contacts U1 snRNA stem-loop 3, which is required for splicing. We suggest that the recruitment of SRSF1 to a U1 snRNP at a 5'SS is the basis for exon definition by U1 snRNP and might be one of the principal functions of U1 snRNPs in the core reactions of splicing in mammals.
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Affiliation(s)
- Andrew M Jobbins
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
- Present address:
MRC London Institute of Medical SciencesLondonUK
- Present address:
Institute of Clinical SciencesImperial College LondonLondonUK
| | - Sébastien Campagne
- Institute of BiochemistryETH ZürichSwitzerland
- Present address:
Inserm U1212CNRS UMR5320ARNA LaboratoryBordeaux CedexFrance
| | - Robert Weinmeister
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
- Leicester Institute of Structural & Chemical Biology and Department of ChemistryUniversity of LeicesterLeicesterUK
| | - Christian M Lucas
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
| | - Alison R Gosliga
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
- Present address:
Institut für Industrielle GenetikAbt.(eilung) SystembiologieUniversität StuttgartStuttgartGermany
| | | | - Li Chen
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
| | - Lucy P Eperon
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
| | - Mark J Hodson
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
| | - Andrew J Hudson
- Leicester Institute of Structural & Chemical Biology and Department of ChemistryUniversity of LeicesterLeicesterUK
| | | | - Ian C Eperon
- Leicester Institute of Structural & Chemical Biology and Department of Molecular & Cell BiologyUniversity of LeicesterLeicesterUK
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11
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Abstract
Herculean efforts by the Wellcome Sanger Institute, the National Cancer Institute, and the National Human Genome Research Institute to sequence thousands of tumors representing all major cancer types have yielded more than 700 genes that contribute to neoplastic growth when mutated, amplified, or deleted. While some of these genes (now included in the COSMIC Cancer Gene Census) encode proteins previously identified in hypothesis-driven experiments (oncogenic transcription factors, protein kinases, etc.), additional classes of cancer drivers have emerged, perhaps none more surprisingly than RNA-binding proteins (RBPs). Over 40 RBPs responsible for virtually all aspects of RNA metabolism, from synthesis to degradation, are recurrently mutated in cancer, and just over a dozen are considered major cancer drivers. This Review investigates whether and how their RNA-binding activities pertain to their oncogenic functions. Focusing on several well-characterized steps in RNA metabolism, we demonstrate that for virtually all cancer-driving RBPs, RNA processing activities are either abolished (the loss-of-function phenotype) or carried out with low fidelity (the LoFi phenotype). Conceptually, this suggests that in normal cells, RBPs act as gatekeepers maintaining proper RNA metabolism and the "balanced" proteome. From the practical standpoint, at least some LoFi phenotypes create therapeutic vulnerabilities, which are beginning to be exploited in the clinic.
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Abstract
PURPOSE OF REVIEW Splicing mutations are among the most recurrent genetic perturbations in hematological malignancies, highlighting an important impact of splicing regulation in hematopoietic development. However, compared to our understanding of splicing factor mutations in hematological malignancies, studies of splicing components and alternative splicing in normal hematopoiesis have been less well investigated. Here, we outline the most recent findings on splicing regulation in normal hematopoiesis and discuss the important questions in the field. RECENT FINDINGS Recent studies have highlighted the critical role of splicing regulation in hematopoiesis, including characterization of splicing components in normal hematopoiesis, investigation of transcriptional alterations on splicing, and identification of stage-specific alternative splicing events during hematopoietic development. SUMMARY These interesting findings provide insights on hematopoietic regulation at a co-transcriptional level. More high-throughput RNA ribonucleic acid (RNA) sequencing and functional genomic screens are needed to advance our knowledge of critical alternative splicing patterns in shaping hematopoiesis.
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Affiliation(s)
- Sisi Chen
- Human Oncology and Pathogenesis Program, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065
- Leukemia Service, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065
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13
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Splicing factor mutations in hematologic malignancies. Blood 2021; 138:599-612. [PMID: 34157091 DOI: 10.1182/blood.2019004260] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/02/2020] [Indexed: 12/15/2022] Open
Abstract
Mutations in genes encoding RNA splicing factors were discovered nearly ten years ago and are now understood to be amongst the most recurrent genetic abnormalities in patients with all forms of myeloid neoplasms and several types of lymphoproliferative disorders as well as subjects with clonal hematopoiesis. These discoveries implicate aberrant RNA splicing, the process by which precursor RNA is converted into mature messenger RNA, in the development of clonal hematopoietic conditions. Both the protein as well as the RNA components of the splicing machinery are affected by mutations at highly specific residues and a number of these mutations alter splicing in a manner distinct from loss of function. Importantly, cells bearing these mutations have now been shown to generate mRNA species with novel aberrant sequences, some of which may be critical to disease pathogenesis and/or novel targets for therapy. These findings have opened new avenues of research to understand biological pathways disrupted by altered splicing. In parallel, multiple studies have revealed that cells bearing change-of-function mutation in splicing factors are preferentially sensitized to any further genetic or chemical perturbations of the splicing machinery. These discoveries are now being pursued in several early phase clinical trials using molecules with diverse mechanisms of action. Here we review the molecular effects of splicing factor mutations on splicing, mechanisms by which these mutations drive clonal transformation of hematopoietic cells, and the development of new therapeutics targeting these genetic subsets of hematopoietic malignancies.
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14
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Liang G, Chen S, Xin S, Dong L. Overexpression of hsa_circ_0001445 reverses oxLDL‑induced inhibition of HUVEC proliferation via SRSF1. Mol Med Rep 2021; 24:507. [PMID: 33982782 PMCID: PMC8134882 DOI: 10.3892/mmr.2021.12146] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 04/21/2021] [Indexed: 02/07/2023] Open
Abstract
Atherosclerosis is a primary cause of multiple types of cardiovascular disease, including myocardial infarction. In addition, injury of human umbilical vein endothelial cells (HUVECs) can lead to the development of atherosclerosis. Circular (circ)RNAs participate in atherosclerosis. It has previously been shown that circRNA cSMARCA5 (hsa_circ_0001445) expression is downregulated in atherosclerosis. However, the effects of hsa_circ_0001445 on the proliferation of HUVECs remain unclear. In order to mimic atherosclerosis in vitro, HUVECs were treated with oxidized low-density lipoprotein (oxLDL). The expression levels of specific genes and proteins were detected in HUVECs by reverse transcription-quantitative PCR and western blot analysis, respectively. Cell proliferation was assessed by Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine staining. Cell apoptosis and 5,5′,6,6′-Tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine staining were examined by flow cytometry. In addition, the association between hsa_circ_0001445 and serine/arginine-rich splicing factor 1 (SRSF1) was investigated by RNA pull-down assay. hsa_circ_0001445 expression was downregulated in oxLDL-treated HUVECs. Moreover, oxLDL-induced inhibition of HUVEC proliferation was significantly reversed by overexpression of hsa_circ_0001445. oxLDL notably inhibited tube formation and mitochondrial membrane potential in HUVECs, while these effects were markedly reversed by hsa_circ_0001445 overexpression. Furthermore, overexpression of hsa_circ_0001445 reversed oxLDL-induced activation of β-catenin by binding to SRSF1. Collectively, these data demonstrated that overexpression of hsa_circ_0001445 reversed oxLDL-induced inhibition of HUVEC proliferation via activation of the SRSF1/β-catenin axis. These findings may provide novel targets for the treatment of atherosclerosis.
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Affiliation(s)
- Guiying Liang
- Department of Cardiology, First People's Hospital of Fuyang District, Hangzhou, Zhejiang 311400, P.R. China
| | - Sihua Chen
- Department of Cardiology, First People's Hospital of Fuyang District, Hangzhou, Zhejiang 311400, P.R. China
| | - Sha Xin
- Department of Cardiology, First People's Hospital of Fuyang District, Hangzhou, Zhejiang 311400, P.R. China
| | - Liang Dong
- Department of Cardiology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang 310009, P.R. China
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15
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Selective Recognition of Amino Acids and Peptides by Small Supramolecular Receptors. Molecules 2020; 26:molecules26010106. [PMID: 33379401 PMCID: PMC7796322 DOI: 10.3390/molecules26010106] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/14/2020] [Accepted: 12/22/2020] [Indexed: 12/30/2022] Open
Abstract
To this day, the recognition and high affinity binding of biomolecules in water by synthetic receptors remains challenging, while the necessity for systems for their sensing, transport and modulation persists. This problematic is prevalent for the recognition of peptides, which not only have key roles in many biochemical pathways, as well as having pharmacological and biotechnological applications, but also frequently serve as models for the study of proteins. Taking inspiration in nature and on the interactions that occur between several receptors and peptide sequences, many researchers have developed and applied a variety of different synthetic receptors, as is the case of macrocyclic compounds, molecular imprinted polymers, organometallic cages, among others, to bind amino acids, small peptides and proteins. In this critical review, we present and discuss selected examples of synthetic receptors for amino acids and peptides, with a greater focus on supramolecular receptors, which show great promise for the selective recognition of these biomolecules in physiological conditions. We decided to focus preferentially on small synthetic receptors (leaving out of this review high molecular weight polymeric systems) for which more detailed and accurate molecular level information regarding the main structural and thermodynamic features of the receptor biomolecule assemblies is available.
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16
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Leclair NK, Brugiolo M, Urbanski L, Lawson SC, Thakar K, Yurieva M, George J, Hinson JT, Cheng A, Graveley BR, Anczuków O. Poison Exon Splicing Regulates a Coordinated Network of SR Protein Expression during Differentiation and Tumorigenesis. Mol Cell 2020; 80:648-665.e9. [PMID: 33176162 PMCID: PMC7680420 DOI: 10.1016/j.molcel.2020.10.019] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 12/18/2022]
Abstract
The RNA isoform repertoire is regulated by splicing factor (SF) expression, and alterations in SF levels are associated with disease. SFs contain ultraconserved poison exon (PE) sequences that exhibit greater identity across species than nearby coding exons, but their physiological role and molecular regulation is incompletely understood. We show that PEs in serine-arginine-rich (SR) proteins, a family of 14 essential SFs, are differentially spliced during induced pluripotent stem cell (iPSC) differentiation and in tumors versus normal tissues. We uncover an extensive cross-regulatory network of SR proteins controlling their expression via alternative splicing coupled to nonsense-mediated decay. We define sequences that regulate PE inclusion and protein expression of the oncogenic SF TRA2β using an RNA-targeting CRISPR screen. We demonstrate location dependency of RS domain activity on regulation of TRA2β-PE using CRISPR artificial SFs. Finally, we develop splice-switching antisense oligonucleotides to reverse the increased skipping of TRA2β-PE detected in breast tumors, altering breast cancer cell viability, proliferation, and migration.
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Affiliation(s)
- Nathan K Leclair
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA
| | - Mattia Brugiolo
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Laura Urbanski
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA
| | - Shane C Lawson
- Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
| | - Ketan Thakar
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Marina Yurieva
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Joshy George
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - John Travis Hinson
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
| | - Albert Cheng
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - Brenton R Graveley
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - Olga Anczuków
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA.
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17
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Chen MX, Zhang KL, Zhang M, Das D, Fang YM, Dai L, Zhang J, Zhu FY. Alternative splicing and its regulatory role in woody plants. TREE PHYSIOLOGY 2020; 40:1475-1486. [PMID: 32589747 DOI: 10.1093/treephys/tpaa076] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/05/2020] [Accepted: 06/16/2020] [Indexed: 05/22/2023]
Abstract
Alternative splicing (AS) is an important post-transcriptional process to enhance proteome diversity in eukaryotic organisms. In plants, numerous reports have primarily focused on AS analysis in model plant species or herbaceous plants, leading to a notable lack of research on AS in woody plants. More importantly, emerging evidence indicates that many important traits, including wood formation and stress resistance, in woody plants are controlled by AS. In this review article, we summarize the current progress of all kinds of AS studies in different tree species at various stages of development and in response to various stresses, revealing the significant role played by AS in woody plants, as well as the similar properties and differential regulation within their herbaceous counterparts. Furthermore, we propose several potential strategies to facilitate the functional characterization of splicing factors in woody plants and evaluate a general pipeline for the systematic characterization of splicing isoforms in a complex AS regulatory network. The utilization of genetic studies and high-throughput omics integration approaches to analyze AS genes and splicing factors is likely to further advance our understanding of AS modulation in woody plants.
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Affiliation(s)
- Mo-Xian Chen
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China
| | - Kai-Lu Zhang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Min Zhang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Debatosh Das
- Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Shatin 999077, Hong Kong
| | - Yan-Ming Fang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Lei Dai
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Jianhua Zhang
- Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Shatin 999077, Hong Kong
| | - Fu-Yuan Zhu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
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18
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Griffin C, Saint-Jeannet JP. Spliceosomopathies: Diseases and mechanisms. Dev Dyn 2020; 249:1038-1046. [PMID: 32506634 DOI: 10.1002/dvdy.214] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/13/2020] [Accepted: 05/27/2020] [Indexed: 12/21/2022] Open
Abstract
The spliceosome is a complex of RNA and proteins that function together to identify intron-exon junctions in precursor messenger-RNAs, splice out the introns, and join the flanking exons. Mutations in any one of the genes encoding the proteins that make up the spliceosome may result in diseases known as spliceosomopathies. While the spliceosome is active in all cell types, with the majority of the proteins presumably expressed ubiquitously, spliceosomopathies tend to be tissue-specific as a result of germ line or somatic mutations, with phenotypes affecting primarily the retina in retinitis pigmentosa, hematopoietic lineages in myelodysplastic syndromes, or the craniofacial skeleton in mandibulofacial dysostosis. Here we describe the major spliceosomopathies, review the proposed mechanisms underlying retinitis pigmentosa and myelodysplastic syndromes, and discuss how this knowledge may inform our understanding of craniofacial spliceosomopathies.
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Affiliation(s)
- Casey Griffin
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, New York, USA
| | - Jean-Pierre Saint-Jeannet
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, New York, USA
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19
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Ozay EI, Shanthalingam S, Torres JA, Osborne BA, Tew GN, Minter LM. Protein Kinase C Theta Modulates PCMT1 through hnRNPL to Regulate FOXP3 Stability in Regulatory T Cells. Mol Ther 2020; 28:2220-2236. [PMID: 32592691 DOI: 10.1016/j.ymthe.2020.06.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/21/2020] [Accepted: 06/10/2020] [Indexed: 10/24/2022] Open
Abstract
T cell receptor signaling, together with cytokine-induced signals, can differentially regulate RNA processing to influence T helper versus regulatory T cell fate. Protein kinase C family members have been shown to function in alternative splicing and RNA processing in various cell types. T cell-specific protein kinase C theta, a molecular regulator of T cell receptor downstream signaling, has been shown to phosphorylate splicing factors and affect post-transcriptional control of T cell gene expression. In this study, we explored how using a synthetic cell-penetrating peptide mimic for intracellular anti-protein kinase C theta delivery fine-tunes differentiation of induced regulatory T cells through its differential effects on RNA processing. We identified protein kinase C theta signaling as a critical modulator of two key RNA regulatory factors, heterogeneous nuclear ribonucleoprotein L (hnRNPL) and protein-l-isoaspartate O-methyltransferase-1 (PCMT1), and loss of protein kinase C theta function initiated a "switch" in post-transcriptional organization in induced regulatory T cells. More interestingly, we discovered that protein-l-isoaspartate O- methyltransferase-1 acts as an instability factor in induced regulatory T cells, by methylating the forkhead box P3 (FOXP3) promoter. Targeting protein-l-isoaspartate O-methyltransferase-1 using a cell-penetrating antibody revealed an efficient means of modulating RNA processing to confer a stable regulatory T cell phenotype.
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Affiliation(s)
- E Ilker Ozay
- Graduate Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Sudarvili Shanthalingam
- Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Joe A Torres
- Graduate Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Barbara A Osborne
- Graduate Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA; Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Gregory N Tew
- Graduate Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA; Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA; Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Lisa M Minter
- Graduate Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA; Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA.
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20
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Prieto C, Kharas MG. RNA Regulators in Leukemia and Lymphoma. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a034967. [PMID: 31615866 DOI: 10.1101/cshperspect.a034967] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Posttranscriptional regulation of mRNA is a powerful and tightly controlled process in which cells command the integrity, diversity, and abundance of their protein products. RNA-binding proteins (RBPs) are the principal players that control many intermediary steps of posttranscriptional regulation. Recent advances in this field have discovered the importance of RBPs in hematological diseases. Herein we will review a number of RBPs that have been determined to play critical functions in leukemia and lymphoma. Furthermore, we will discuss the potential therapeutic strategies that are currently being studied to specifically target RBPs in these diseases.
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Affiliation(s)
- Camila Prieto
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Michael G Kharas
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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21
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Shotwell CR, Cleary JD, Berglund JA. The potential of engineered eukaryotic RNA-binding proteins as molecular tools and therapeutics. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1573. [PMID: 31680457 DOI: 10.1002/wrna.1573] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/21/2019] [Accepted: 10/08/2019] [Indexed: 02/06/2023]
Abstract
Eukaroytic RNA-binding proteins (RBPs) recognize and process RNAs through recognition of their sequence motifs via RNA-binding domains (RBDs). RBPs usually consist of one or more RBDs and can include additional functional domains that modify or cleave RNA. Engineered RBPs have been used to answer basic biology questions, control gene expression, locate viral RNA in vivo, as well as many other tasks. Given the growing number of diseases associated with RNA and RBPs, engineered RBPs also have the potential to serve as therapeutics. This review provides an in depth description of recent advances in engineered RBPs and discusses opportunities and challenges in the field. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Methods > RNA Nanotechnology RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Carl R Shotwell
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida
| | - John D Cleary
- RNA Institute, University at Albany, Albany, New York
| | - J Andrew Berglund
- Department of Biological Sciences and RNA Institute, University at Albany, Albany, New York
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22
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Sajini AA, Choudhury NR, Wagner RE, Bornelöv S, Selmi T, Spanos C, Dietmann S, Rappsilber J, Michlewski G, Frye M. Loss of 5-methylcytosine alters the biogenesis of vault-derived small RNAs to coordinate epidermal differentiation. Nat Commun 2019; 10:2550. [PMID: 31186410 PMCID: PMC6560067 DOI: 10.1038/s41467-019-10020-7] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/09/2019] [Indexed: 12/20/2022] Open
Abstract
The presence and absence of RNA modifications regulates RNA metabolism by modulating the binding of writer, reader, and eraser proteins. For 5-methylcytosine (m5C) however, it is largely unknown how it recruits or repels RNA-binding proteins. Here, we decipher the consequences of m5C deposition into the abundant non-coding vault RNA VTRNA1.1. Methylation of cytosine 69 in VTRNA1.1 occurs frequently in human cells, is exclusively mediated by NSUN2, and determines the processing of VTRNA1.1 into small-vault RNAs (svRNAs). We identify the serine/arginine rich splicing factor 2 (SRSF2) as a novel VTRNA1.1-binding protein that counteracts VTRNA1.1 processing by binding the non-methylated form with higher affinity. Both NSUN2 and SRSF2 orchestrate the production of distinct svRNAs. Finally, we discover a functional role of svRNAs in regulating the epidermal differentiation programme. Thus, our data reveal a direct role for m5C in the processing of VTRNA1.1 that involves SRSF2 and is crucial for efficient cellular differentiation.
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Affiliation(s)
- Abdulrahim A Sajini
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
- Department of Biomedical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates
- Department of Medical Laboratory Technology, University of Tabuk, Tabuk, P.O. Box 71491, Saudi Arabia
| | - Nila Roy Choudhury
- Division of Infection and Pathway Medicine, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Rebecca E Wagner
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Susanne Bornelöv
- Wellcome MRC Cambridge Stem Cell Institute, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Tommaso Selmi
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Christos Spanos
- Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Sabine Dietmann
- Wellcome MRC Cambridge Stem Cell Institute, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh, EH9 3BF, UK
- Department of Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Gracjan Michlewski
- Division of Infection and Pathway Medicine, University of Edinburgh, The Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK.
- Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh, EH9 3BF, UK.
- ZJU-UoE Institute, Zhejiang University, 718 East Haizhou Road, Haining, Zhejiang, 314400, P.R. China.
| | - Michaela Frye
- Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.
- German Cancer Research Centre (Deutsches Krebsforschungszentrum, DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.
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23
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Amberg N, Sotiropoulou PA, Heller G, Lichtenberger BM, Holcmann M, Camurdanoglu B, Baykuscheva-Gentscheva T, Blanpain C, Sibilia M. EGFR Controls Hair Shaft Differentiation in a p53-Independent Manner. iScience 2019; 15:243-256. [PMID: 31082735 PMCID: PMC6515155 DOI: 10.1016/j.isci.2019.04.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/15/2019] [Accepted: 04/15/2019] [Indexed: 12/31/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) signaling controls skin development and homeostasis in mice and humans, and its deficiency causes severe skin inflammation, which might affect epidermal stem cell behavior. Here, we describe the inflammation-independent effects of EGFR deficiency during skin morphogenesis and in adult hair follicle stem cells. Expression and alternative splicing analysis of RNA sequencing data from interfollicular epidermis and outer root sheath indicate that EGFR controls genes involved in epidermal differentiation and also in centrosome function, DNA damage, cell cycle, and apoptosis. Genetic experiments employing p53 deletion in EGFR-deficient epidermis reveal that EGFR signaling exhibits p53-dependent functions in proliferative epidermal compartments, as well as p53-independent functions in differentiated hair shaft keratinocytes. Loss of EGFR leads to absence of LEF1 protein specifically in the innermost epithelial hair layers, resulting in disorganization of medulla cells. Thus, our results uncover important spatial and temporal features of cell-autonomous EGFR functions in the epidermis.
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Affiliation(s)
- Nicole Amberg
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria
| | - Panagiota A Sotiropoulou
- Interdisciplinary Research Institute (IRIBHM), Université Libre Bruxelles, Bruxelles 1070, Belgium
| | - Gerwin Heller
- Department of Medicine I, Comprehensive Cancer Center, Clinical Division of Oncology, Medical University of Vienna, Vienna 1090, Austria
| | - Beate M Lichtenberger
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria
| | - Martin Holcmann
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria
| | - Bahar Camurdanoglu
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria
| | - Temenuschka Baykuscheva-Gentscheva
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria
| | - Cedric Blanpain
- Interdisciplinary Research Institute (IRIBHM), Université Libre Bruxelles, Bruxelles 1070, Belgium; WELBIO, Interdisciplinary Research Institute (IRIBHM), Université Libre Bruxelles, Bruxelles 1070, Belgium
| | - Maria Sibilia
- Institute of Cancer Research, Department of Internal Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna 1090, Austria.
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24
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Zhou X, Wang R, Li X, Yu L, Hua D, Sun C, Shi C, Luo W, Rao C, Jiang Z, Feng Y, Wang Q, Yu S. Splicing factor SRSF1 promotes gliomagenesis via oncogenic splice-switching of MYO1B. J Clin Invest 2019; 129:676-693. [PMID: 30481162 DOI: 10.1172/jci120279] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 11/20/2018] [Indexed: 02/06/2023] Open
Abstract
Abnormal alternative splicing (AS) caused by alterations to splicing factors contributes to tumor progression. Serine/arginine splicing factor 1 (SRSF1) has emerged as a key oncodriver in numerous solid tumors, leaving its roles and mechanisms largely obscure in glioma. Here, we demonstrate that SRSF1 is increased in glioma tissues and cell lines. Moreover, its expression was correlated positively with tumor grade and Ki-67 index, but inversely with patient survival. Using RNA-Seq, we comprehensively screened and identified multiple SRSF1-affected AS events. Motif analysis revealed a position-dependent modulation of AS by SRSF1 in glioma. Functionally, we verified that SRSF1 promoted cell proliferation, survival, and invasion by specifically switching the AS of the myosin IB (MYO1B) gene and facilitating the expression of the oncogenic and membrane-localized isoform, MYO1B-fl. Strikingly, MYO1B splicing was dysregulated in parallel with SRSF1 expression in gliomas and predicted the poor prognosis of the patients. Further investigation revealed that SRSF1-guided AS of the MYO1B gene increased the tumorigenic potential of glioma cells through the PDK1/AKT and PAK/LIMK pathways. Taken together, we identify SRSF1 as an important oncodriver that integrates AS control of MYO1B into promotion of gliomagenesis and represents a potential prognostic biomarker and target for glioma therapy.
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Affiliation(s)
- Xuexia Zhou
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Run Wang
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Xuebing Li
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Environment, Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China
| | - Lin Yu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences of Tianjin Medical University, Tianjin, China
| | - Dan Hua
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Cuiyun Sun
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Cuijuan Shi
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Wenjun Luo
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Chun Rao
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Zhendong Jiang
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Ying Feng
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Qian Wang
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Shizhu Yu
- Department of Neuropathology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Injuries, Variations and Regeneration of the Nervous System, Tianjin, China.,Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
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25
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Mao M, Hu Y, Yang Y, Qian Y, Wei H, Fan W, Yang Y, Li X, Wang Z. Modeling and Predicting the Activities of Trans-Acting Splicing Factors with Machine Learning. Cell Syst 2018; 7:510-520.e4. [PMID: 30414922 DOI: 10.1016/j.cels.2018.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 05/10/2018] [Accepted: 09/19/2018] [Indexed: 02/06/2023]
Abstract
Alternative splicing (AS) is generally regulated by trans-splicing factors that specifically bind to cis-elements in pre-mRNAs. The human genome encodes ∼1,500 RNA binding proteins (RBPs) that potentially regulate AS, yet their functions remain largely unknown. To explore their potential activities, we fused the putative functional domains of RBPs to a sequence-specific RNA-binding domain and systemically analyzed how these engineered factors affect splicing. We discovered that ∼80% of low-complexity domains in endogenous RBPs displayed distinct context-dependent activities in regulating splicing, indicating that AS is under more extensive regulation than previously expected. We developed a machine learning approach to classify and predict the activities of RBPs based on their sequence compositions and further validated this model using endogenous RBPs and synthetic polypeptides. These results represent a systematic inspection, modeling, prediction, and validation of how RBP sequences affect their activities in controlling splicing, paving the way for de novo engineering of artificial splicing factors.
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Affiliation(s)
- Miaowei Mao
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China; Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Yue Hu
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yun Yang
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yajie Qian
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Huanhuan Wei
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Wei Fan
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Yi Yang
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaoling Li
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Zefeng Wang
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China.
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26
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Jang HN, Liu Y, Choi N, Oh J, Ha J, Zheng X, Shen H. Binding of SRSF4 to a novel enhancer modulates splicing of exon 6 of Fas pre-mRNA. Biochem Biophys Res Commun 2018; 506:703-708. [PMID: 30376989 DOI: 10.1016/j.bbrc.2018.10.123] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 10/20/2018] [Indexed: 11/29/2022]
Abstract
Alternative splicing of exon 6 in Fas pre-mRNA generates a membrane bound pro-apoptotic isoform or soluble anti-apoptotic isoform. SRSF4 is a member of Arginine-Serine rich (SR) protein family. Here we demonstrate that increased SRSF4 expression stimulates exon 6 inclusion, and that reduced SRSF4 expression promotes exon 6 exclusion. We also show that weaker but not stronger 5' splice-site strength of exon 6 abolishes the SRSF4 effects on exon 6 splicing. Furthermore, we identified a novel enhancer on exon 6, on which SRSF4 interacts functionally and physically. Our results illustrate a novel regulatory mechanism of Fas pre-mRNA splicing.
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Affiliation(s)
- Ha Na Jang
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea
| | - Yongchao Liu
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea
| | - Namjeong Choi
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea
| | - Jagyeong Oh
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea
| | - Jiyeon Ha
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea
| | - Xuexiu Zheng
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea.
| | - Haihong Shen
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 500-712, South Korea.
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27
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SRSF2 mutations drive oncogenesis by activating a global program of aberrant alternative splicing in hematopoietic cells. Leukemia 2018; 32:2659-2671. [PMID: 29858584 PMCID: PMC6274620 DOI: 10.1038/s41375-018-0152-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 03/20/2018] [Accepted: 04/20/2018] [Indexed: 01/30/2023]
Abstract
Recurrent mutations in the splicing factor SRSF2 are associated with poor clinical outcomes in myelodysplastic syndromes (MDS). Their high frequency suggests these mutations drive oncogenesis, yet the molecular explanation for this process is unclear. SRSF2 mutations could directly affect pre-mRNA splicing of a vital gene product; alternatively, a whole network of gene products could be affected. Here we determine how SRSF2 mutations globally affect RNA binding and splicing in vivo using HITS-CLIP. Remarkably, the majority of differential binding events do not translate into alternative splicing of exons with SRSF2P95H binding sites. Alternative splice alterations appear to be dominated by indirect effects. Importantly, SRSF2P95H targets are enriched in RNA processing and splicing genes, including several members of the hnRNP and SR families of proteins, suggesting a "splicing-cascade" phenotype wherein mutation of a single splicing factor leads to widespread modifications in multiple RNA processing and splicing proteins. We show that splice alteration of HNRNPA2B1, a splicing factor differentially bound and spliced by SRSF2P95H, impairs hematopoietic differentiation in vivo. Our data suggests a model whereby the recurrent mutations in splicing factors set off a cascade of gene regulatory events that together affect hematopoiesis and drive cancer.
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28
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Alternative splicing and cancer metastasis: prognostic and therapeutic applications. Clin Exp Metastasis 2018; 35:393-402. [PMID: 29845349 DOI: 10.1007/s10585-018-9905-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/22/2018] [Indexed: 12/12/2022]
Abstract
Metastatic cells exhibit an extraordinary phenotypic plasticity, not only in adapting to unfamiliar microenvironments but also in surviving aggressive treatments and immune responses. A major source of phenotypic variability is alternative splicing (AS) of the pre-messenger RNA. This process is catalyzed by one of the most complex pieces of cellular molecular regulatory events, the spliceosome, which is composed of ribonucleoproteins and polypeptides termed spliceosome factors. With strong evidence indicating that AS affects nearly all genes encoded by the human genome, aberrant AS programs have a significant impact on cancer cell development and progression. In this review, we present insights about the genomic and epigenomic factors affecting AS, summarize the most recent findings linking aberrant AS to metastatic progression, and highlight potential prognostic and therapeutic applications.
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29
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Arbab Jafari P, Ayatollahi H, Sadeghi R, Sheikhi M, Asghari A. Prognostic significance of SRSF2 mutations in myelodysplastic syndromes and chronic myelomonocytic leukemia: a meta-analysis. ACTA ACUST UNITED AC 2018; 23:778-784. [PMID: 29757120 DOI: 10.1080/10245332.2018.1471794] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
OBJECTIVE Serine/arginine-rich splicing factor 2 (SRSF2) mutations were detected frequently in myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) patients. However, its prognostic value has not yet been fully clarified. METHODS In this meta-analysis, Hazard Ratio (HR) and 95% confidence interval (CI) for overall-survival (OS) were chosen to evaluate the prognostic impact of SRSF2 mutations and to compare SRSF2 mutations to those with wild-type. RESULTS A total of 2056 patients from 12 studies were obtained. The pooled HRs for OSsuggested that patients with MDS had a poorer prognosis (HR = 1.780, 95% CI (1.410-2.249)), while analysis on SRSF2 mutations revealed no significant effect on the prognosis of CMML patients (HR = 1.091, 95% CI (0.925-1.286)). The frequency of SRSF2 mutations was found to be 11.5% and 39.8% in patients with MDS and CMML, respectively. DISCUSSION This meta-analysis suggests that SRSF2 has a poor prognosis in patients with MDS, but no prognosis impact on patients with CMML. CONCLUSION In conclusion, SRSF2 mutations were significantly related to the shorter OS in patients with MDS which may consider as an adverse prognostic risk factor. Whereas, analysis did not show any prognostic effect on OS of CMML patients with SRSF2 mutations.
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Affiliation(s)
- Pourya Arbab Jafari
- a Department of Hematology and Blood Banking, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Hossein Ayatollahi
- a Department of Hematology and Blood Banking, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Ramin Sadeghi
- b Department of Nuclear Medicine, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Maryam Sheikhi
- c Cancer Molecular Pathology Research Center, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
| | - Amir Asghari
- d Department of Physiology, Faculty of Medicine , Mashhad University of Medical Sciences , Mashhad , Iran
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30
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Lin P, Luo Y, Zhu S, Maggio D, Yang H, Hu C, Wang J, Zhang H, Ren Y, Zhou X, Mei C, Ma L, Xu W, Ye L, Zhuang Z, Jin J, Tong H. Isocitrate dehydrogenase 2 mutations correlate with leukemic transformation and are predicted by 2-hydroxyglutarate in myelodysplastic syndromes. J Cancer Res Clin Oncol 2018; 144:1037-1047. [PMID: 29549529 DOI: 10.1007/s00432-018-2627-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/12/2018] [Indexed: 12/01/2022]
Abstract
PURPOSE The myelodysplastic syndromes (MDS) are a group of hematologic disorders characterized by the presence of somatically mutated hematopoietic stem cells (HSCs) that increase the risk of progression to secondary acute myeloid leukemia (sAML). Mutations in isocitrate dehydrogenase (IDHmut) are thought to correlate with the increased production of the oncogenic protein 2-hydroxyglutarate (2-HG) in AML. The aim of this study was to examine whether serum 2-HG has utility as a prognostic biomarker, and whether elevated 2-HG levels are predictive of IDH mutations in patients with MDS. METHODS Genetic profiling was utilized to determine the genetic composition of a large cohort of MDS patients, including the presence or absence of IDH1 or IDH2 mutations (n = 281). Serum 2-HG levels were detected by liquid chromatography-tandem mass spectrometry. RESULTS In the current study of MDS patients, elevated serum 2-HG levels were predictive of inferior overall- and leukemia-free survival irrespective of IPSS risk grouping. Higher serum 2-HG levels predicted the presence of IDH mutations. IDH2mut patients had a higher risk of leukemic transformation. The co-occurrence of DNMT3A or SRSF2 mutations was found to be increased in IDH2mut patients. IDH2 mutations were associated with significantly worse OS and LFS amongst patients with low-risk MDS by IPSS grouping. CONCLUSIONS The noted predictive value of serum 2-HG levels and IDH2 mutations on OS and LFS support the use of biomarkers and/or underlying cytogenetics in novel prognostic scoring systems for MDS.
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Affiliation(s)
- Peipei Lin
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Yingwan Luo
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Shuanghong Zhu
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Dominic Maggio
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Haiyang Yang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Chao Hu
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Jinghan Wang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Hua Zhang
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Yanling Ren
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Xinping Zhou
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Chen Mei
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Liya Ma
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Weilai Xu
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Li Ye
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Zhengping Zhuang
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Jie Jin
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Hongyan Tong
- Department of Hematology, The First Affiliated Hospital, Zhejiang University, No. 79 Qingchun Road, Hangzhou, 310003, People's Republic of China. .,Myelodysplastic Syndromes Diagnosis and Therapy center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China. .,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.
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31
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Lim CS, Brown CM. Know Your Enemy: Successful Bioinformatic Approaches to Predict Functional RNA Structures in Viral RNAs. Front Microbiol 2018; 8:2582. [PMID: 29354101 PMCID: PMC5758548 DOI: 10.3389/fmicb.2017.02582] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/11/2017] [Indexed: 12/14/2022] Open
Abstract
Structured RNA elements may control virus replication, transcription and translation, and their distinct features are being exploited by novel antiviral strategies. Viral RNA elements continue to be discovered using combinations of experimental and computational analyses. However, the wealth of sequence data, notably from deep viral RNA sequencing, viromes, and metagenomes, necessitates computational approaches being used as an essential discovery tool. In this review, we describe practical approaches being used to discover functional RNA elements in viral genomes. In addition to success stories in new and emerging viruses, these approaches have revealed some surprising new features of well-studied viruses e.g., human immunodeficiency virus, hepatitis C virus, influenza, and dengue viruses. Some notable discoveries were facilitated by new comparative analyses of diverse viral genome alignments. Importantly, comparative approaches for finding RNA elements embedded in coding and non-coding regions differ. With the exponential growth of computer power we have progressed from stem-loop prediction on single sequences to cutting edge 3D prediction, and from command line to user friendly web interfaces. Despite these advances, many powerful, user friendly prediction tools and resources are underutilized by the virology community.
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Affiliation(s)
- Chun Shen Lim
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Chris M Brown
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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32
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Mahas A, Neal Stewart C, Mahfouz MM. Harnessing CRISPR/Cas systems for programmable transcriptional and post-transcriptional regulation. Biotechnol Adv 2018; 36:295-310. [DOI: 10.1016/j.biotechadv.2017.11.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/03/2017] [Accepted: 11/27/2017] [Indexed: 12/26/2022]
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33
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Physiological Srsf2 P95H expression causes impaired hematopoietic stem cell functions and aberrant RNA splicing in mice. Blood 2017; 131:621-635. [PMID: 29146882 DOI: 10.1182/blood-2017-01-762393] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 11/09/2017] [Indexed: 12/15/2022] Open
Abstract
Splicing factor mutations are characteristic of myelodysplastic syndromes (MDS) and related myeloid neoplasms and implicated in their pathogenesis, but their roles in the development of MDS have not been fully elucidated. In the present study, we investigated the consequence of mutant Srsf2 expression using newly generated Vav1-Cre-mediated conditional knockin mice. Mice carrying a heterozygous Srsf2 P95H mutation showed significantly reduced numbers of hematopoietic stem and progenitor cells (HSPCs) and differentiation defects both in the steady-state condition and transplantation settings. Srsf2-mutated hematopoietic stem cells (HSCs) showed impaired long-term reconstitution compared with control mice in competitive repopulation assays. Although the Srsf2 mutant mice did not develop MDS under the steady-state condition, when their stem cells were transplanted into lethally irradiated mice, the recipients developed anemia, leukopenia, and erythroid dysplasia, which suggests the role of replicative stress in the development of an MDS-like phenotype in Srsf2-mutated mice. RNA sequencing of the Srsf2-mutated HSPCs revealed a number of abnormal splicing events and differentially expressed genes, including several potential targets implicated in the pathogenesis of hematopoietic malignancies, such as Csf3r, Fyn, Gnas, Nsd1, Hnrnpa2b1, and Trp53bp1 Among the mutant Srsf2-associated splicing events, most commonly observed were the enhanced inclusion and/or exclusion of cassette exons, which were caused by the altered consensus motifs for the recognition of exonic splicing enhancers. Our findings suggest that the mutant Srsf2 leads to a compromised HSC function by causing abnormal RNA splicing and expression, contributing to the deregulated hematopoiesis that recapitulates the MDS phenotypes, possibly as a result of additional genetic and/or environmental insults.
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34
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Armstrong RN, Steeples V, Singh S, Sanchi A, Boultwood J, Pellagatti A. Splicing factor mutations in the myelodysplastic syndromes: target genes and therapeutic approaches. Adv Biol Regul 2017; 67:13-29. [PMID: 28986033 DOI: 10.1016/j.jbior.2017.09.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 09/19/2017] [Accepted: 09/21/2017] [Indexed: 10/25/2022]
Abstract
Mutations in splicing factor genes (SF3B1, SRSF2, U2AF1 and ZRSR2) are frequently found in patients with myelodysplastic syndromes (MDS), suggesting that aberrant spliceosome function plays a key role in the pathogenesis of MDS. Splicing factor mutations have been shown to result in aberrant splicing of many downstream target genes. Recent functional studies have begun to characterize the splicing dysfunction in MDS, identifying some key aberrantly spliced genes that are implicated in disease pathophysiology. These findings have led to the development of therapeutic strategies using splicing-modulating agents and rapid progress is being made in this field. Splicing inhibitors are promising agents that exploit the preferential sensitivity of splicing factor-mutant cells to these compounds. Here, we review the known target genes associated with splicing factor mutations in MDS, and discuss the potential of splicing-modulating therapies for these disorders.
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Affiliation(s)
- Richard N Armstrong
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK
| | - Violetta Steeples
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK
| | - Shalini Singh
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK
| | - Andrea Sanchi
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK
| | - Jacqueline Boultwood
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK.
| | - Andrea Pellagatti
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and Oxford BRC Haematology Theme, Oxford, UK.
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35
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Mutations of RNA splicing factors in hematological malignancies. Cancer Lett 2017; 409:1-8. [PMID: 28888996 DOI: 10.1016/j.canlet.2017.08.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/22/2017] [Accepted: 08/28/2017] [Indexed: 01/01/2023]
Abstract
Systematic large-scale cancer genomic studies have produced numerous significant findings. These studies have not only revealed new cancer-promoting genes, but they also have identified cancer-promoting functions of previously known "housekeeping" genes. These studies have identified numerous mutations in genes which play a fundamental role in nuclear precursor mRNA splicing. Somatic mutations and copy number variation in many of the splicing factors which participate in the formation of multiple spliceosomal complexes appear to play a role in many cancers and in particular in myelodysplastic syndromes (MDS). Mutated proteins seem to interfere with the recognition of the authentic splice sites (SS) leading to utilization of suboptimal alternative splicing sites generating aberrantly spliced mRNA isoforms. This short review is focusing on the function of the splice factors involved in the formation of splicing complexes and potential mechanisms which affect usage of the authentic splice site recognition.
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Pnrc2 regulates 3'UTR-mediated decay of segmentation clock-associated transcripts during zebrafish segmentation. Dev Biol 2017. [PMID: 28648842 DOI: 10.1016/j.ydbio.2017.06.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Vertebrate segmentation is controlled by the segmentation clock, a molecular oscillator that regulates gene expression and cycles rapidly. The expression of many genes oscillates during segmentation, including hairy/Enhancer of split-related (her or Hes) genes, which encode transcriptional repressors that auto-inhibit their own expression, and deltaC (dlc), which encodes a Notch ligand. We previously identified the tortuga (tor) locus in a zebrafish forward genetic screen for genes involved in cyclic transcript regulation and showed that cyclic transcripts accumulate post-splicing in tor mutants. Here we show that cyclic mRNA accumulation in tor mutants is due to loss of pnrc2, which encodes a proline-rich nuclear receptor co-activator implicated in mRNA decay. Using an inducible in vivo reporter system to analyze transcript stability, we find that the her1 3'UTR confers Pnrc2-dependent instability to a heterologous transcript. her1 mRNA decay is Dicer-independent and likely employs a Pnrc2-Upf1-containing mRNA decay complex. Surprisingly, despite accumulation of cyclic transcripts in pnrc2-deficient embryos, we find that cyclic protein is expressed normally. Overall, we show that Pnrc2 promotes 3'UTR-mediated decay of developmentally-regulated segmentation clock transcripts and we uncover an additional post-transcriptional regulatory layer that ensures oscillatory protein expression in the absence of cyclic mRNA decay.
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Wei HH, Liu Y, Wang Y, Lu Q, Yang X, Li J, Wang Z. Engineering Artificial Factors to Specifically Manipulate Alternative Splicing in Human Cells. J Vis Exp 2017. [PMID: 28518098 DOI: 10.3791/54967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The processing of most eukaryotic RNAs is mediated by RNA Binding Proteins (RBPs) with modular configurations, including an RNA recognition module, which specifically binds the pre-mRNA target and an effector domain. Previously, we have taken advantage of the unique RNA binding mode of the PUF domain in human Pumilio 1 to generate a programmable RNA binding scaffold, which was used to engineer various artificial RBPs to manipulate RNA metabolism. Here, a detailed protocol is described to construct Engineered Splicing Factors (ESFs) that are specifically designed to modulate the alternative splicing of target genes. The protocol includes how to design and construct a customized PUF scaffold for a specific RNA target, how to construct an ESF expression plasmid by fusing a designer PUF domain and an effector domain, and how to use ESFs to manipulate the splicing of target genes. In the representative results of this method, we have also described the common assays of ESF activities using splicing reporters, the application of ESF in cultured human cells, and the subsequent effect of splicing changes. By following the detailed protocols in this report, it is possible to design and generate ESFs for the regulation of different types of Alternative Splicing (AS), providing a new strategy to study splicing regulation and the function of different splicing isoforms. Moreover, by fusing different functional domains with a designed PUF domain, researchers can engineer artificial factors that target specific RNAs to manipulate various steps of RNA processing.
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Affiliation(s)
- Huan-Huan Wei
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS)
| | - Yuanlong Liu
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS)
| | - Yang Wang
- Institute of Cancer Stem Cell, Second Affiliated Hospital, Cancer Center, Dalian Medical University
| | - Qianyun Lu
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS)
| | - Xuerong Yang
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS)
| | - Jiefu Li
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS)
| | - Zefeng Wang
- Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences (SIBS);
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Wu W, Zong J, Wei N, Cheng J, Zhou X, Cheng Y, Chen D, Guo Q, Zhang B, Feng Y. CASH: a constructing comprehensive splice site method for detecting alternative splicing events. Brief Bioinform 2017; 19:905-917. [DOI: 10.1093/bib/bbx034] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Indexed: 01/03/2023] Open
Affiliation(s)
- Wenwu Wu
- The State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Lin’an, Hangzhou, China
| | - Jie Zong
- Novel Bioinformatics Co., Ltd, Shanghai, China
| | - Ning Wei
- Institute for Nutritional Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Jian Cheng
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Xuexia Zhou
- Tianjin Medical University General Hospital, China
| | - Yuanming Cheng
- Institute for Nutritional Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Dai Chen
- Novel Bioinformatics Co., Ltd, Shanghai, China
| | - Qinghua Guo
- Novel Bioinformatics Co., Ltd, Shanghai, China
| | - Bo Zhang
- Novel Bioinformatics Co., Ltd, Shanghai, China
| | - Ying Feng
- Institute for Nutritional Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
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Yan Q, Xia X, Sun Z, Fang Y. Depletion of Arabidopsis SC35 and SC35-like serine/arginine-rich proteins affects the transcription and splicing of a subset of genes. PLoS Genet 2017; 13:e1006663. [PMID: 28273088 PMCID: PMC5362245 DOI: 10.1371/journal.pgen.1006663] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 03/22/2017] [Accepted: 02/28/2017] [Indexed: 12/23/2022] Open
Abstract
Serine/arginine-rich (SR) proteins are important splicing factors which play significant roles in spliceosome assembly and splicing regulation. However, little is known regarding their biological functions in plants. Here, we analyzed the phenotypes of mutants upon depleting different subfamilies of Arabidopsis SR proteins. We found that loss of the functions of SC35 and SC35-like (SCL) proteins cause pleiotropic changes in plant morphology and development, including serrated leaves, late flowering, shorter roots and abnormal silique phyllotaxy. Using RNA-seq, we found that SC35 and SCL proteins play roles in the pre-mRNA splicing. Motif analysis revealed that SC35 and SCL proteins preferentially bind to a specific RNA sequence containing the AGAAGA motif. In addition, the transcriptions of a subset of genes are affected by the deletion of SC35 and SCL proteins which interact with NRPB4, a specific subunit of RNA polymerase II. The splicing of FLOWERING LOCUS C (FLC) intron1 and transcription of FLC were significantly regulated by SC35 and SCL proteins to control Arabidopsis flowering. Therefore, our findings provide mechanistic insight into the functions of plant SC35 and SCL proteins in the regulation of splicing and transcription in a direct or indirect manner to maintain the proper expression of genes and development. SR proteins were identified to be important splicing factors. This work generated mutants of different subfamilies of the classic Arabidopsis SR proteins. Genetic analysis revealed that loss of the function of SC35/SCL proteins influences the plant development. This study revealed SC35/SCL proteins regulate alternative splicing, preferentially bind a specific RNA motif, interact with NRPB4, and affect the transcription of a subset of genes. This study further revealed that SC35/SCL proteins control flowering by regulating the splicing and transcription of FLC. These results shed light on the functions of SR proteins in plants.
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Affiliation(s)
- Qingqing Yan
- National key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Xi Xia
- National key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Zhenfei Sun
- National key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Yuda Fang
- National key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
- * E-mail:
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40
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Splicing factor gene mutations in hematologic malignancies. Blood 2016; 129:1260-1269. [PMID: 27940478 DOI: 10.1182/blood-2016-10-692400] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/25/2016] [Indexed: 01/27/2023] Open
Abstract
Alternative splicing generates a diversity of messenger RNA (mRNA) transcripts from a single mRNA precursor and contributes to the complexity of our proteome. Splicing is perturbed by a variety of mechanisms in cancer. Recurrent mutations in splicing factors have emerged as a hallmark of several hematologic malignancies. Splicing factor mutations tend to occur in the founding clone of myeloid cancers, and these mutations have recently been identified in blood cells from normal, healthy elderly individuals with clonal hematopoiesis who are at increased risk of subsequently developing a hematopoietic malignancy, suggesting that these mutations contribute to disease initiation. Splicing factor mutations change the pattern of splicing in primary patient and mouse hematopoietic cells and alter hematopoietic differentiation and maturation in animal models. Recent developments in this field are reviewed here, with an emphasis on the clinical consequences of splicing factor mutations, mechanistic insights from animal models, and implications for development of novel therapies targeting the precursor mRNA splicing pathway.
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41
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Hillebrand F, Peter JO, Brillen AL, Otte M, Schaal H, Erkelenz S. Differential hnRNP D isoform incorporation may confer plasticity to the ESSV-mediated repressive state across HIV-1 exon 3. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1860:205-217. [PMID: 27919832 DOI: 10.1016/j.bbagrm.2016.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 11/22/2016] [Accepted: 12/01/2016] [Indexed: 11/27/2022]
Abstract
Even though splicing repression by hnRNP complexes bound to exonic sequences is well-documented, the responsible effector domains of hnRNP proteins have been described for only a select number of hnRNP constituents. Thus, there is only limited information available for possible varying silencer activities amongst different hnRNP proteins and composition changes within possible hnRNP complex assemblies. In this study, we identified the glycine-rich domain (GRD) of hnRNP proteins as a unifying feature in splice site repression. We also show that all four hnRNP D isoforms can act as genuine splicing repressors when bound to exonic positions. The presence of an extended GRD, however, seemed to potentiate the hnRNP D silencer activity of isoforms p42 and p45. Moreover, we demonstrate that hnRNP D proteins associate with the HIV-1 ESSV silencer complex, probably through direct recognition of "UUAG" sequences overlapping with the previously described "UAGG" motifs bound by hnRNP A1. Consequently, this spatial proximity seems to cause mutual interference between hnRNP A1 and hnRNP D. This interplay between hnRNP A1 and D facilitates a dynamic regulation of the repressive state of HIV-1 exon 3 which manifests as fluctuating relative levels of spliced vpr- and unspliced gag/pol-mRNAs.
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Affiliation(s)
- Frank Hillebrand
- Institute of Virology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jan Otto Peter
- Institute of Virology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anna-Lena Brillen
- Institute of Virology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Marianne Otte
- Institute of Evolutionary Genetics, Heinrich-Heine-University Duesseldorf, Duesseldorf, Germany
| | - Heiner Schaal
- Institute of Virology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Steffen Erkelenz
- Institute of Virology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany; Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
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42
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Larsen SC, Sylvestersen KB, Mund A, Lyon D, Mullari M, Madsen MV, Daniel JA, Jensen LJ, Nielsen ML. Proteome-wide analysis of arginine monomethylation reveals widespread occurrence in human cells. Sci Signal 2016; 9:rs9. [DOI: 10.1126/scisignal.aaf7329] [Citation(s) in RCA: 187] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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43
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Zhang J, Loyd MR, Randall MS, Morris JJ, Shah JG, Ney PA. Repression by RB1 characterizes genes involved in the penultimate stage of erythroid development. Cell Cycle 2016; 14:3441-53. [PMID: 26397180 DOI: 10.1080/15384101.2015.1090067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Retinoblastoma-1 (RB1), and the RB1-related proteins p107 and p130, are key regulators of the cell cycle. Although RB1 is required for normal erythroid development in vitro, it is largely dispensable for erythropoiesis in vivo. The modest phenotype caused by RB1 deficiency in mice raises questions about redundancy within the RB1 family, and the role of RB1 in erythroid differentiation. Here we show that RB1 is the major pocket protein that regulates terminal erythroid differentiation. Erythroid cells lacking all pocket proteins exhibit the same cell cycle defects as those deficient for RB1 alone. RB1 has broad repressive effects on gene transcription in erythroid cells. As a group, RB1-repressed genes are generally well expressed but downregulated at the final stage of erythroid development. Repression correlates with E2F binding, implicating E2Fs in the recruitment of RB1 to repressed genes. Merging differential and time-dependent changes in expression, we define a group of approximately 800 RB1-repressed genes. Bioinformatics analysis shows that this list is enriched for terms related to the cell cycle, but also for terms related to terminal differentiation. Some of these have not been previously linked to RB1. These results expand the range of processes potentially regulated by RB1, and suggest that a principal role of RB1 in development is coordinating the events required for terminal differentiation.
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Affiliation(s)
- Ji Zhang
- a Department of Biochemistry ; St. Jude Children's Research Hospital ; Memphis , TN USA.,b Current address: Cancer Biology & Genetics; Memorial Sloan-Kettering Cancer Center ; New York , NY USA
| | - Melanie R Loyd
- a Department of Biochemistry ; St. Jude Children's Research Hospital ; Memphis , TN USA.,c Hartwell Center for Bioinformatics and Biotechnology; St. Jude Children's Research Hospital ; Memphis , TN USA
| | - Mindy S Randall
- a Department of Biochemistry ; St. Jude Children's Research Hospital ; Memphis , TN USA
| | - John J Morris
- c Hartwell Center for Bioinformatics and Biotechnology; St. Jude Children's Research Hospital ; Memphis , TN USA
| | - Jayesh G Shah
- d Cell & Molecular Biology; Lindsley F. Kimball Research Institute; New York Blood Center ; New York , NY USA
| | - Paul A Ney
- a Department of Biochemistry ; St. Jude Children's Research Hospital ; Memphis , TN USA.,d Cell & Molecular Biology; Lindsley F. Kimball Research Institute; New York Blood Center ; New York , NY USA.,e Current address: 1735 York Ave., New York , NY USA
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44
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Pellagatti A, Boultwood J. Splicing factor gene mutations in the myelodysplastic syndromes: impact on disease phenotype and therapeutic applications. Adv Biol Regul 2016; 63:59-70. [PMID: 27639445 DOI: 10.1016/j.jbior.2016.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 08/18/2016] [Accepted: 08/18/2016] [Indexed: 01/05/2023]
Abstract
Splicing factor gene mutations are the most frequent mutations found in patients with the myeloid malignancy myelodysplastic syndrome (MDS), suggesting that spliceosomal dysfunction plays a major role in disease pathogenesis. The aberrantly spliced target genes and deregulated cellular pathways associated with the commonly mutated splicing factor genes in MDS (SF3B1, SRSF2 and U2AF1) are being identified, illuminating the molecular mechanisms underlying MDS. Emerging data from mouse modeling studies indicate that the presence of splicing factor gene mutations can lead to bone marrow hematopoietic stem/myeloid progenitor cell expansion, impaired hematopoiesis and dysplastic differentiation that are hallmarks of MDS. Importantly, recent evidence suggests that spliceosome inhibitors and splicing modulators may have therapeutic value in the treatment of splicing factor mutant myeloid malignancies.
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Affiliation(s)
- Andrea Pellagatti
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford; NIHR Biomedical Research Centre, Oxford, UK.
| | - Jacqueline Boultwood
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford; NIHR Biomedical Research Centre, Oxford, UK.
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45
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Abstract
The recent genomic characterization of cancers has revealed recurrent somatic point mutations and copy number changes affecting genes encoding RNA splicing factors. Initial studies of these 'spliceosomal mutations' suggest that the proteins bearing these mutations exhibit altered splice site and/or exon recognition preferences relative to their wild-type counterparts, resulting in cancer-specific mis-splicing. Such changes in the splicing machinery may create novel vulnerabilities in cancer cells that can be therapeutically exploited using compounds that can influence the splicing process. Further studies to dissect the biochemical, genomic and biological effects of spliceosomal mutations are crucial for the development of cancer therapies targeted at these mutations.
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Affiliation(s)
- Heidi Dvinge
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Eunhee Kim
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Leukemia Service, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Robert K. Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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46
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Inoue D, Bradley RK, Abdel-Wahab O. Spliceosomal gene mutations in myelodysplasia: molecular links to clonal abnormalities of hematopoiesis. Genes Dev 2016; 30:989-1001. [PMID: 27151974 PMCID: PMC4863743 DOI: 10.1101/gad.278424.116] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Genomic analyses of the myeloid malignancies and clonal disorders of hematopoiesis that may give rise to these disorders have identified that mutations in genes encoding core spliceosomal proteins and accessory regulatory splicing factors are among the most common targets of somatic mutations. These spliceosomal mutations often occur in a mutually exclusive manner with one another and, in aggregate, account for the most frequent class of mutations in patients with myelodysplastic syndromes (MDSs) in particular. Although substantial progress has been made in understanding the effects of several of these mutations on splicing and splice site recognition, functional connections linking the mechanistic changes in splicing induced by these mutations to the phenotypic consequences of clonal and aberrant hematopoiesis are not yet well defined. This review describes our current understanding of the mechanistic and biological effects of spliceosomal gene mutations in MDSs as well as the regulation of splicing throughout normal hematopoiesis.
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Affiliation(s)
- Daichi Inoue
- Human Oncology and Pathogenesis Program, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Robert K Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA; Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA; Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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47
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HIV-1 and M-PMV RNA Nuclear Export Elements Program Viral Genomes for Distinct Cytoplasmic Trafficking Behaviors. PLoS Pathog 2016; 12:e1005565. [PMID: 27070420 PMCID: PMC4829213 DOI: 10.1371/journal.ppat.1005565] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/21/2016] [Indexed: 12/15/2022] Open
Abstract
Retroviruses encode cis-acting RNA nuclear export elements that override nuclear retention of intron-containing viral mRNAs including the full-length, unspliced genomic RNAs (gRNAs) packaged into assembling virions. The HIV-1 Rev-response element (RRE) recruits the cellular nuclear export receptor CRM1 (also known as exportin-1/XPO1) using the viral protein Rev, while simple retroviruses encode constitutive transport elements (CTEs) that directly recruit components of the NXF1(Tap)/NXT1(p15) mRNA nuclear export machinery. How gRNA nuclear export is linked to trafficking machineries in the cytoplasm upstream of virus particle assembly is unknown. Here we used long-term (>24 h), multicolor live cell imaging to directly visualize HIV-1 gRNA nuclear export, translation, cytoplasmic trafficking, and virus particle production in single cells. We show that the HIV-1 RRE regulates unique, en masse, Rev- and CRM1-dependent "burst-like" transitions of mRNAs from the nucleus to flood the cytoplasm in a non-localized fashion. By contrast, the CTE derived from Mason-Pfizer monkey virus (M-PMV) links gRNAs to microtubules in the cytoplasm, driving them to cluster markedly to the centrosome that forms the pericentriolar core of the microtubule-organizing center (MTOC). Adding each export element to selected heterologous mRNAs was sufficient to confer each distinct export behavior, as was directing Rev/CRM1 or NXF1/NXT1 transport modules to mRNAs using a site-specific RNA tethering strategy. Moreover, multiple CTEs per transcript enhanced MTOC targeting, suggesting that a cooperative mechanism links NXF1/NXT1 to microtubules. Combined, these results reveal striking, unexpected features of retroviral gRNA nucleocytoplasmic transport and demonstrate roles for mRNA export elements that extend beyond nuclear pores to impact gRNA distribution in the cytoplasm.
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48
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Lee JM, Nobumori C, Tu Y, Choi C, Yang SH, Jung HJ, Vickers TA, Rigo F, Bennett CF, Young SG, Fong LG. Modulation of LMNA splicing as a strategy to treat prelamin A diseases. J Clin Invest 2016; 126:1592-602. [PMID: 26999604 DOI: 10.1172/jci85908] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 01/14/2016] [Indexed: 01/08/2023] Open
Abstract
The alternatively spliced products of LMNA, lamin C and prelamin A (the precursor to lamin A), are produced in similar amounts in most tissues and have largely redundant functions. This redundancy suggests that diseases, such as Hutchinson-Gilford progeria syndrome (HGPS), that are caused by prelamin A-specific mutations could be treated by shifting the output of LMNA more toward lamin C. Here, we investigated mechanisms that regulate LMNA mRNA alternative splicing and assessed the feasibility of reducing prelamin A expression in vivo. We identified an exon 11 antisense oligonucleotide (ASO) that increased lamin C production at the expense of prelamin A when transfected into mouse and human fibroblasts. The same ASO also reduced the expression of progerin, the mutant prelamin A protein in HGPS, in fibroblasts derived from patients with HGPS. Mechanistic studies revealed that the exon 11 sequences contain binding sites for serine/arginine-rich splicing factor 2 (SRSF2), and SRSF2 knockdown lowered lamin A production in cells and in murine tissues. Moreover, administration of the exon 11 ASO reduced lamin A expression in wild-type mice and progerin expression in an HGPS mouse model. Together, these studies identify ASO-mediated reduction of prelamin A as a potential strategy to treat prelamin A-specific diseases.
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49
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Wang Y, Wang Z. Design of RNA-Binding Proteins: Manipulate Alternative Splicing in Human Cells with Artificial Splicing Factors. Methods Mol Biol 2016; 1421:227-41. [PMID: 26965269 DOI: 10.1007/978-1-4939-3591-8_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The majority of human genes undergo alternative splicing to produce multiple isoforms with distinct functions. The dysregulations of alternative splicing have been found to be closely associated with various human diseases; thus new approaches to modulate disease-associated splicing events will provide great therapeutic potentials. Here we report protocols for constructing novel artificial splicing factors that can be designed to specifically modulate alternative splicing of target genes. By following the method outlined in this protocol, it is possible to design and generate artificial splicing factors with diverse activities in regulating different types of alternative splicing. The artificial splicing factors can be used to change splicing of either minigenes or endogenous genes in cultured human cells, providing a new strategy to study the regulation of alternative splicing and function of alternatively spliced products.
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Affiliation(s)
- Yang Wang
- Institute of Cancer Stem Cell, Cancer Center, Dalian Medical University, Dalian, 116044, China
| | - Zefeng Wang
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, CB # 7365, 120 Mason Farm Road, Chapel Hill, NC, 27599, USA.
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50
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Tethered Function Assays as Tools to Elucidate the Molecular Roles of RNA-Binding Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:61-88. [PMID: 27256382 DOI: 10.1007/978-3-319-29073-7_3] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Dynamic regulation of RNA molecules is critical to the survival and development of cells. Messenger RNAs are transcribed in the nucleus as intron-containing pre-mRNAs and bound by RNA-binding proteins, which control their fate by regulating RNA stability, splicing, polyadenylation, translation, and cellular localization. Most RBPs have distinct mRNA-binding and functional domains; thus, the function of an RBP can be studied independently of RNA-binding by artificially recruiting the RBP to a reporter RNA and then measuring the effect of RBP recruitment on reporter splicing, stability, translational efficiency, or intracellular trafficking. These tethered function assays therefore do not require prior knowledge of the RBP's endogenous RNA targets or its binding sites within these RNAs. Here, we provide an overview of the experimental strategy and the strengths and limitations of common tethering systems. We illustrate specific examples of the application of the assay in elucidating the function of various classes of RBPs. We also discuss how classic tethering assay approaches and insights gained from them have been empowered by more recent technological advances, including efficient genome editing and high-throughput RNA-sequencing.
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