1
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Nian Q, Li Y, Li J, Zhao L, Rodrigues Lima F, Zeng J, Liu R, Ye Z. U2AF1 in various neoplastic diseases and relevant targeted therapies for malignant cancers with complex mutations (Review). Oncol Rep 2024; 51:5. [PMID: 37975232 PMCID: PMC10688450 DOI: 10.3892/or.2023.8664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023] Open
Abstract
U2 small nuclear RNA auxiliary factor 1 (U2AF1) is a multifunctional protein that plays a crucial role in the regulation of RNA splicing during eukaryotic gene expression. U2AF1 belongs to the SR family of splicing factors and is involved in the removal of introns from mRNAs and exon-exon binding. Mutations in U2AF1 are frequently observed in myelodysplastic syndrome, primary myelofibrosis, chronic myelomonocytic leukaemia, hairy cell leukaemia and other solid tumours, particularly in lung, pancreatic, and ovarian carcinomas. Therefore, targeting U2AF1 for therapeutic interventions may be a viable strategy for treating malignant diseases. In the present review, the pathogenic mechanisms associated with U2AF1 in different malignant diseases were summarized, and the potential of related targeting agents was discussed. Additionally, the feasibility of natural product-based therapies directed against U2AF1 was explored.
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Affiliation(s)
- Qing Nian
- Department of Transfusion, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, P.R. China
| | - Yihui Li
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, P.R. China
| | - Jingwei Li
- Department of Transfusion, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, P.R. China
| | - Liyun Zhao
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, P.R. China
| | - Fernando Rodrigues Lima
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, 75013 Paris, France
| | - Jinhao Zeng
- Department of Gastroenterology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610000, P.R. China
| | - Rongxing Liu
- Department of Pharmacy, The Second Affiliated Hospital, Army Medical University, Chongqing 400000, P.R. China
| | - Zhijun Ye
- Department of Clinical Nutrition, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, P.R. China
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2
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Liu J, Chen Y, Nong B, Luo X, Cui K, Li Z, Zhang P, Tan W, Yang Y, Ma W, Liang P, Songyang Z. CRISPR-assisted transcription activation by phase-separation proteins. Protein Cell 2023; 14:874-887. [PMID: 36905356 PMCID: PMC10691850 DOI: 10.1093/procel/pwad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/11/2023] [Indexed: 03/12/2023] Open
Abstract
The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system has been widely used for genome engineering and transcriptional regulation in many different organisms. Current CRISPR-activation (CRISPRa) platforms often require multiple components because of inefficient transcriptional activation. Here, we fused different phase-separation proteins to dCas9-VPR (dCas9-VP64-P65-RTA) and observed robust increases in transcriptional activation efficiency. Notably, human NUP98 (nucleoporin 98) and FUS (fused in sarcoma) IDR domains were best at enhancing dCas9-VPR activity, with dCas9-VPR-FUS IDR (VPRF) outperforming the other CRISPRa systems tested in this study in both activation efficiency and system simplicity. dCas9-VPRF overcomes the target strand bias and widens gRNA designing windows without affecting the off-target effect of dCas9-VPR. These findings demonstrate the feasibility of using phase-separation proteins to assist in the regulation of gene expression and support the broad appeal of the dCas9-VPRF system in basic and clinical applications.
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Affiliation(s)
- Jiaqi Liu
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yuxi Chen
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Baoting Nong
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
| | - Xiao Luo
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Kaixin Cui
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhan Li
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Pengfei Zhang
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | | | - Yue Yang
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Wenbin Ma
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Puping Liang
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhou Songyang
- State Key Laboratory of Biocontrol, MOE Key Laboratory of Gene Function and Regulation and Guangzhou Key Laboratory of Healthy Aging Research, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
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3
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Bonner EA, Lee SC. Therapeutic Targeting of RNA Splicing in Cancer. Genes (Basel) 2023; 14:1378. [PMID: 37510283 PMCID: PMC10379351 DOI: 10.3390/genes14071378] [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] [Received: 06/06/2023] [Revised: 06/25/2023] [Accepted: 06/27/2023] [Indexed: 07/30/2023] Open
Abstract
RNA splicing is a key regulatory step in the proper control of gene expression. It is a highly dynamic process orchestrated by the spliceosome, a macro-molecular machinery that consists of protein and RNA components. The dysregulation of RNA splicing has been observed in many human pathologies ranging from neurodegenerative diseases to cancer. The recent identification of recurrent mutations in the core components of the spliceosome in hematologic malignancies has advanced our knowledge of how splicing alterations contribute to disease pathogenesis. This review article will discuss our current understanding of how aberrant RNA splicing regulation drives tumor initiation and progression. We will also review current therapeutic modalities and highlight emerging technologies designed to target RNA splicing for cancer treatment.
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Affiliation(s)
- Elizabeth A. Bonner
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA;
- Translational Science and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Stanley C. Lee
- Translational Science and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98195, USA
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4
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Glasser E, Maji D, Biancon G, Puthenpeedikakkal A, Cavender C, Tebaldi T, Jenkins J, Mathews D, Halene S, Kielkopf C. Pre-mRNA splicing factor U2AF2 recognizes distinct conformations of nucleotide variants at the center of the pre-mRNA splice site signal. Nucleic Acids Res 2022; 50:5299-5312. [PMID: 35524551 PMCID: PMC9128377 DOI: 10.1093/nar/gkac287] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/03/2022] [Accepted: 04/12/2022] [Indexed: 11/24/2022] Open
Abstract
The essential pre-mRNA splicing factor U2AF2 (also called U2AF65) identifies polypyrimidine (Py) tract signals of nascent transcripts, despite length and sequence variations. Previous studies have shown that the U2AF2 RNA recognition motifs (RRM1 and RRM2) preferentially bind uridine-rich RNAs. Nonetheless, the specificity of the RRM1/RRM2 interface for the central Py tract nucleotide has yet to be investigated. We addressed this question by determining crystal structures of U2AF2 bound to a cytidine, guanosine, or adenosine at the central position of the Py tract, and compared U2AF2-bound uridine structures. Local movements of the RNA site accommodated the different nucleotides, whereas the polypeptide backbone remained similar among the structures. Accordingly, molecular dynamics simulations revealed flexible conformations of the central, U2AF2-bound nucleotide. The RNA binding affinities and splicing efficiencies of structure-guided mutants demonstrated that U2AF2 tolerates nucleotide substitutions at the central position of the Py tract. Moreover, enhanced UV-crosslinking and immunoprecipitation of endogenous U2AF2 in human erythroleukemia cells showed uridine-sensitive binding sites, with lower sequence conservation at the central nucleotide positions of otherwise uridine-rich, U2AF2-bound splice sites. Altogether, these results highlight the importance of RNA flexibility for protein recognition and take a step towards relating splice site motifs to pre-mRNA splicing efficiencies.
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Affiliation(s)
- Eliezra Glasser
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
| | - Debanjana Maji
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
| | - Giulia Biancon
- Section of Hematology, Department of Internal Medicine and
Yale Cancer Center, Yale University School of Medicine,
New Haven,
CT 06520, USA
| | | | - Chapin E Cavender
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
| | - Toma Tebaldi
- Section of Hematology, Department of Internal Medicine and
Yale Cancer Center, Yale University School of Medicine,
New Haven,
CT 06520, USA
- Department of Cellular, Computational and Integrative Biology
(CIBIO), University of
Trento, Trento, Italy
| | - Jermaine L Jenkins
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
| | - David H Mathews
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
| | - Stephanie Halene
- Section of Hematology, Department of Internal Medicine and
Yale Cancer Center, Yale University School of Medicine,
New Haven,
CT 06520, USA
- Yale Center for RNA Science and Medicine, Yale University
School of Medicine, New Haven,
CT 06520, USA
- Department of Pathology, Yale University School of
Medicine, New Haven,
CT 06520, USA
| | - Clara L Kielkopf
- Department of Biochemistry and Biophysics, and the Center for
RNA Biology, University of Rochester School of Medicine and
Dentistry, Rochester,
NY 14642, USA
- Wilmot Cancer Institute, University of Rochester School of
Medicine and Dentistry, Rochester,
NY 14642, USA
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5
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Fujita KI, Ishizuka T, Mitsukawa M, Kurata M, Masuda S. Regulating Divergent Transcriptomes through mRNA Splicing and Its Modulation Using Various Small Compounds. Int J Mol Sci 2020; 21:ijms21062026. [PMID: 32188117 PMCID: PMC7139312 DOI: 10.3390/ijms21062026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/11/2020] [Accepted: 03/12/2020] [Indexed: 12/14/2022] Open
Abstract
Human transcriptomes are more divergent than genes and contribute to the sophistication of life. This divergence is derived from various isoforms arising from alternative splicing. In addition, alternative splicing regulated by spliceosomal factors and RNA structures, such as the RNA G-quadruplex, is important not only for isoform diversity but also for regulating gene expression. Therefore, abnormal splicing leads to serious diseases such as cancer and neurodegenerative disorders. In the first part of this review, we describe the regulation of divergent transcriptomes using alternative mRNA splicing. In the second part, we present the relationship between the disruption of splicing and diseases. Recently, various compounds with splicing inhibitor activity were established. These splicing inhibitors are recognized as a biological tool to investigate the molecular mechanism of splicing and as a potential therapeutic agent for cancer treatment. Food-derived compounds with similar functions were found and are expected to exhibit anticancer effects. In the final part, we describe the compounds that modulate the messenger RNA (mRNA) splicing process and their availability for basic research and future clinical potential.
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6
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Sun C. The SF3b complex: splicing and beyond. Cell Mol Life Sci 2020; 77:3583-3595. [PMID: 32140746 PMCID: PMC7452928 DOI: 10.1007/s00018-020-03493-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/13/2020] [Accepted: 02/20/2020] [Indexed: 12/17/2022]
Abstract
The SF3b complex is an intrinsic component of the functional U2 small nuclear ribonucleoprotein (snRNP). As U2 snRNP enters nuclear pre-mRNA splicing, SF3b plays key roles in recognizing the branch point sequence (BPS) and facilitating spliceosome assembly and activation. Since the discovery of SF3b, substantial progress has been made in elucidating its molecular mechanism during splicing. In addition, numerous recent studies indicate that SF3b and its components are engaged in various molecular and cellular events that are beyond the canonical role in splicing. This review summarizes the current knowledge on the SF3b complex and highlights its multiple roles in splicing and beyond.
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Affiliation(s)
- Chengfu Sun
- Non-coding RNA and Drug Discovery Key Laboratory of Sichuan Province, Chengdu Medical College, Chengdu, 610500, China.
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7
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Taylor J, Lee SC. Mutations in spliceosome genes and therapeutic opportunities in myeloid malignancies. Genes Chromosomes Cancer 2019; 58:889-902. [PMID: 31334570 PMCID: PMC6852509 DOI: 10.1002/gcc.22784] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 07/17/2019] [Indexed: 12/21/2022] Open
Abstract
Since the discovery of RNA splicing more than 40 years ago, our comprehension of the molecular events orchestrating constitutive and alternative splicing has greatly improved. Dysregulation of pre-mRNA splicing has been observed in many human diseases including neurodegenerative diseases and cancer. The recent identification of frequent somatic mutations in core components of the spliceosome in myeloid malignancies and functional analysis using model systems has advanced our knowledge of how splicing alterations contribute to disease pathogenesis. In this review, we summarize our current understanding on the mechanisms of how mutant splicing factors impact splicing and the resulting functional and pathophysiological consequences. We also review recent advances to develop novel therapeutic approaches targeting splicing catalysis and splicing regulatory proteins, and discuss emerging technologies using oligonucleotide-based therapies to modulate pathogenically spliced isoforms.
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Affiliation(s)
- Justin Taylor
- Human Oncology and Pathogenesis ProgramMemorial Sloan Kettering Cancer CenterNew YorkNew York
- Leukemia Service, Department of MedicineMemorial Sloan Kettering Cancer CenterNew YorkNew York
| | - Stanley C. Lee
- Human Oncology and Pathogenesis ProgramMemorial Sloan Kettering Cancer CenterNew YorkNew York
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8
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Desterro J, Bak-Gordon P, Carmo-Fonseca M. Targeting mRNA processing as an anticancer strategy. Nat Rev Drug Discov 2019; 19:112-129. [PMID: 31554928 DOI: 10.1038/s41573-019-0042-3] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2019] [Indexed: 12/19/2022]
Abstract
Discoveries in the past decade have highlighted the potential of mRNA as a therapeutic target for cancer. Specifically, RNA sequencing revealed that, in addition to gene mutations, alterations in mRNA can contribute to the initiation and progression of cancer. Indeed, precursor mRNA processing, which includes the removal of introns by splicing and the formation of 3' ends by cleavage and polyadenylation, is frequently altered in tumours. These alterations result in numerous cancer-specific mRNAs that generate altered levels of normal proteins or proteins with new functions, leading to the activation of oncogenes or the inactivation of tumour-suppressor genes. Abnormally spliced and polyadenylated mRNAs are also associated with resistance to cancer treatment and, unexpectedly, certain cancers are highly sensitive to the pharmacological inhibition of splicing. This Review summarizes recent progress in our understanding of how splicing and polyadenylation are altered in cancer and highlights how this knowledge has been translated for drug discovery, resulting in the production of small molecules and oligonucleotides that modulate the spliceosome and are in clinical trials for the treatment of cancer.
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Affiliation(s)
- Joana Desterro
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto Português de Oncologia de Lisboa, Serviço de Hematologia, Lisboa, Portugal
| | - Pedro Bak-Gordon
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
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9
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Palangat M, Anastasakis DG, Fei DL, Lindblad KE, Bradley R, Hourigan CS, Hafner M, Larson DR. The splicing factor U2AF1 contributes to cancer progression through a noncanonical role in translation regulation. Genes Dev 2019; 33:482-497. [PMID: 30842218 PMCID: PMC6499322 DOI: 10.1101/gad.319590.118] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 02/15/2019] [Indexed: 01/07/2023]
Abstract
Palangat et al. uncovered a noncanonical function of U2AF1, showing that it directly binds mature mRNA in the cytoplasm and negatively regulates mRNA translation. Somatic mutations in the genes encoding components of the spliceosome occur frequently in human neoplasms, including myeloid dysplasias and leukemias, and less often in solid tumors. One of the affected factors, U2AF1, is involved in splice site selection, and the most common change, S34F, alters a conserved nucleic acid-binding domain, recognition of the 3′ splice site, and alternative splicing of many mRNAs. However, the role that this mutation plays in oncogenesis is still unknown. Here, we uncovered a noncanonical function of U2AF1, showing that it directly binds mature mRNA in the cytoplasm and negatively regulates mRNA translation. This splicing-independent role of U2AF1 is altered by the S34F mutation, and polysome profiling indicates that the mutation affects translation of hundreds of mRNA. One functional consequence is increased synthesis of the secreted chemokine interleukin 8, which contributes to metastasis, inflammation, and cancer progression in mice and humans.
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Affiliation(s)
- Murali Palangat
- Laboratory of Receptor Biology and Gene Expression, National Cancer Insitute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Dimitrios G Anastasakis
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | | - Katherine E Lindblad
- Laboratory of Myeloid Malignancies, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Robert Bradley
- Computational Biology Program, Public Health Sciences and Biological Sciences, Fred Hutchinson Cancer Center, Seattle, Washington 98109, USA
| | - Christopher S Hourigan
- Laboratory of Myeloid Malignancies, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Markus Hafner
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Daniel R Larson
- Laboratory of Receptor Biology and Gene Expression, National Cancer Insitute, National Institutes of Health, Bethesda, Maryland 20892, USA
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10
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Aujla A, Linder K, Iragavarapu C, Karass M, Liu D. SRSF2 mutations in myelodysplasia/myeloproliferative neoplasms. Biomark Res 2018; 6:29. [PMID: 30275952 PMCID: PMC6158887 DOI: 10.1186/s40364-018-0142-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 08/27/2018] [Indexed: 12/12/2022] Open
Abstract
Recurrent gene mutations have been described with varying frequencies in myelodysplasia (MDS) /myeloproliferative neoplasm (MPN) overlap syndromes (MMOS). Recent work has placed significant focus on understanding the role of gene lesions involving the spliceosomal machinery in leukemogeneis. SRSF2 is a gene encoding critical spliceosomal proteins. SRSF2 mutations appear to play an important role in pathogenesis of MMOS, particularly in chronic myelomonocytic leukemia. Inhibition of splicing may be a new therapeutic approach. E7107, a spliceosome inhibitor, has been shown to differentially inhibit splicing more in SRSF2-mutant cells leading to decreased leukemia burden in mice. H3B-8800 is a small molecule modulator of spliceosome complex and has been shown to lower leukemia burden in SRSF2-P95H mutant mice. This review focuses on the incidence of mutant SRSF2 across various MMOS as well as recent clinical development of spliceosome inhibitors.
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Affiliation(s)
- Amandeep Aujla
- 1Department of Medicine, New York Medical College and Westchester Medical Center, Valhalla, NY USA
| | - Katherine Linder
- 2Section of Hematology-Oncology, Department of Medicine, Baylor College of Medicine, Houston, TX USA
| | - Chaitanya Iragavarapu
- 3Division of Blood and Marrow Transplantation, Department of Medicine, Stanford University, Stanford, CA USA
| | - Michael Karass
- 1Department of Medicine, New York Medical College and Westchester Medical Center, Valhalla, NY USA
| | - Delong Liu
- 1Department of Medicine, New York Medical College and Westchester Medical Center, Valhalla, NY USA.,4The affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, 127 Dongming Road, Zhengzhou, 450008 China
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11
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Abstract
During erythropoiesis, hematopoietic stem and progenitor cells transition to erythroblasts en route to terminal differentiation into enucleated red blood cells. Transcriptome-wide changes underlie distinct morphological and functional characteristics at each cell division during this process. Many studies of gene expression have historically been carried out in erythroblasts, and the biogenesis of β-globin mRNA—the most highly expressed transcript in erythroblasts—was the focus of many seminal studies on the mechanisms of pre-mRNA splicing. We now understand that pre-mRNA splicing plays an important role in shaping the transcriptome of developing erythroblasts. Recent advances have provided insight into the role of alternative splicing and intron retention as important regulatory mechanisms of erythropoiesis. However, dysregulation of splicing during erythropoiesis is also a cause of several hematological diseases, including β-thalassemia and myelodysplastic syndromes. With a growing understanding of the role that splicing plays in these diseases, we are well poised to develop gene-editing treatments. In this review, we focus on changes in the developing erythroblast transcriptome caused by alternative splicing, the molecular basis of splicing-related blood diseases, and therapeutic advances in disease treatment using CRISPR/Cas9 gene editing.
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Affiliation(s)
- Kirsten A Reimer
- Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, 06520, USA
| | - Karla M Neugebauer
- Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, 06520, USA
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12
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Carrocci TJ, Paulson JC, Hoskins AA. Functional analysis of Hsh155/SF3b1 interactions with the U2 snRNA/branch site duplex. RNA (NEW YORK, N.Y.) 2018; 24:1028-1040. [PMID: 29752352 PMCID: PMC6049509 DOI: 10.1261/rna.065664.118] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/10/2018] [Indexed: 05/25/2023]
Abstract
SF3b1 is an essential component of the U2 snRNP implicated in branch site (BS) recognition and found to be frequently mutated in several human cancers. While recent structures of yeast and human SF3b1 have revealed its molecular architecture, the importance of specific RNA:protein contacts and conformational changes remains largely uncharacterized. Here, we performed mutational analysis of yeast SF3b1, guided by recent structures of the spliceosome. We find that conserved amino acids contacting the U2 snRNA backbone of the U2/BS duplex are nonessential, and that yeast can tolerate truncation of the HEAT repeats containing these amino acids. The pocket housing the branchpoint adenosine (BP-A) is also amenable to mutation despite strong conservation. However, mutations that support viability can still lead to defects in splicing pre-mRNAs with nonconsensus BS substitutions found at -3, -2, -1, and +1 positions relative to the BP-A or at the branchpoint position. Through the generation of yeast and human chimeric proteins, we further defined the functionally conserved regions of Hsh155 as well as identify changes in BS usage resulting from inclusion of human SF3b1 HEAT repeats. Moreover, these chimeric proteins confer a sensitivity to small molecule inhibition by pladienolide B to yeast splicing. Together, these data reveal the importance of individual contacts of Hsh155/SF3b1 to the U2/BS duplex and define their contribution to BS usage by the spliceosome.
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Affiliation(s)
- Tucker J Carrocci
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Joshua C Paulson
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Aaron A Hoskins
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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13
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Tefferi A, Finke CM, Lasho TL, Hanson CA, Ketterling RP, Gangat N, Pardanani A. U2AF1 mutation types in primary myelofibrosis: phenotypic and prognostic distinctions. Leukemia 2018. [PMID: 29535431 PMCID: PMC6170397 DOI: 10.1038/s41375-018-0078-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Ayalew Tefferi
- Division of Hematology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA.
| | - Christy M Finke
- Division of Hematology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Terra L Lasho
- Division of Hematology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Curtis A Hanson
- Division of Hematopathology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Rhett P Ketterling
- Division of Cytogenetics, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Naseema Gangat
- Division of Hematology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Animesh Pardanani
- Division of Hematology, Departments of Medicine and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
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