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Gleneadie HJ, Fernandez-Ruiz B, Sardini A, Van de Pette M, Dimond A, Prinjha RK, McGinty J, French PMW, Bagci H, Merkenschlager M, Fisher AG. Endogenous bioluminescent reporters reveal a sustained increase in utrophin gene expression upon EZH2 and ERK1/2 inhibition. Commun Biol 2023; 6:318. [PMID: 36966198 PMCID: PMC10039851 DOI: 10.1038/s42003-023-04666-9] [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: 12/16/2022] [Accepted: 03/06/2023] [Indexed: 03/27/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked disorder caused by loss of function mutations in the dystrophin gene (Dmd), resulting in progressive muscle weakening. Here we modelled the longitudinal expression of endogenous Dmd, and its paralogue Utrn, in mice and in myoblasts by generating bespoke bioluminescent gene reporters. As utrophin can partially compensate for Dmd-deficiency, these reporters were used as tools to ask whether chromatin-modifying drugs can enhance Utrn expression in developing muscle. Myoblasts treated with different PRC2 inhibitors showed significant increases in Utrn transcripts and bioluminescent signals, and these responses were independently verified by conditional Ezh2 deletion. Inhibition of ERK1/2 signalling provoked an additional increase in Utrn expression that was also seen in Dmd-mutant cells, and maintained as myoblasts differentiate. These data reveal PRC2 and ERK1/2 to be negative regulators of Utrn expression and provide specialised molecular imaging tools to monitor utrophin expression as a therapeutic strategy for DMD.
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Affiliation(s)
- Hannah J Gleneadie
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Beatriz Fernandez-Ruiz
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Alessandro Sardini
- Whole Animal Physiology and Imaging Facility, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Mathew Van de Pette
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
- MRC Toxicology Unit, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Andrew Dimond
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Rab K Prinjha
- Immunology and Epigenetics Research Unit, Research, GlaxoSmithKline, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - James McGinty
- Photonics Group, Department of Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
| | - Paul M W French
- Photonics Group, Department of Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
| | - Hakan Bagci
- Lymphocyte Development Group, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Matthias Merkenschlager
- Lymphocyte Development Group, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Amanda G Fisher
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK.
- Department of Biochemistry, University of Oxford, South Parks Road, OX1 3QU, Oxford, UK.
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Georgieva AM, Guo X, Bartkuhn M, Günther S, Künne C, Smolka C, Atzberger A, Gärtner U, Mamchaoui K, Bober E, Zhou Y, Yuan X, Braun T. Inactivation of Sirt6 ameliorates muscular dystrophy in mdx mice by releasing suppression of utrophin expression. Nat Commun 2022; 13:4184. [PMID: 35859073 PMCID: PMC9300598 DOI: 10.1038/s41467-022-31798-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/30/2022] [Indexed: 11/18/2022] Open
Abstract
The NAD+-dependent SIRT1-7 family of protein deacetylases plays a vital role in various molecular pathways related to stress response, DNA repair, aging and metabolism. Increased activity of individual sirtuins often exerts beneficial effects in pathophysiological conditions whereas reduced activity is usually associated with disease conditions. Here, we demonstrate that SIRT6 deacetylates H3K56ac in myofibers to suppress expression of utrophin, a dystrophin-related protein stabilizing the sarcolemma in absence of dystrophin. Inactivation of Sirt6 in dystrophin-deficient mdx mice reduced damage of myofibers, ameliorated dystrophic muscle pathology, and improved muscle function, leading to attenuated activation of muscle stem cells (MuSCs). ChIP-seq and locus-specific recruitment of SIRT6 using a CRISPR-dCas9/gRNA approach revealed that SIRT6 is critical for removal of H3K56ac at the Downstream utrophin Enhancer (DUE), which is indispensable for utrophin expression. We conclude that epigenetic manipulation of utrophin expression is a promising approach for the treatment of Duchenne Muscular Dystrophy (DMD). Utrophin is a dystrophin-related protein stabilizing the sarcolemma in absence of dystrophin. Here the authors report that inactivation of the protein deacetylase SIRT6, involved in the deacetylation of the epigenetic mark H3K56ac in muscle cells, increases expression of utrophin and ameliorates dystrophic muscle pathology in mice.
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Affiliation(s)
- Angelina M Georgieva
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Xinyue Guo
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Marek Bartkuhn
- Biomedical Informatics and Systems Medicine, Justus Liebig University, Giessen, Germany
| | - Stefan Günther
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Carsten Künne
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Christian Smolka
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Ann Atzberger
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Ulrich Gärtner
- Institute for Anatomy and Cell Biology, University of Giessen, Giessen, Germany
| | - Kamel Mamchaoui
- Sorbonne Université, Inserm, Institut de Myologie, Centre de Recherche en Myologie, F-75013, Paris, France
| | - Eva Bober
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Yonggang Zhou
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany
| | - Xuejun Yuan
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany.
| | - Thomas Braun
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany.
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Nogami K, Maruyama Y, Elhussieny A, Sakai-Takemura F, Tanihata J, Kira JI, Miyagoe-Suzuki Y, Takeda S. iNOS is not responsible for RyR1 S-nitrosylation in mdx mice with truncated dystrophin. BMC Musculoskelet Disord 2020; 21:479. [PMID: 32693782 PMCID: PMC7374827 DOI: 10.1186/s12891-020-03501-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/13/2020] [Indexed: 11/30/2022] Open
Abstract
Background Previous research indicated that nitric oxide synthase (NOS) is the key molecule for S-nitrosylation of ryanodine receptor 1 (RyR1) in DMD model mice (mdx mice) and that both neuronal NOS (nNOS) and inducible NOS (iNOS) might contribute to the reaction because nNOS is mislocalized in the cytoplasm and iNOS expression is higher in mdx mice. We investigated the effect of iNOS on RyR1 S-nitrosylation in mdx mice and whether transgenic expression of truncated dystrophin reduced iNOS expression in mdx mice or not. Methods Three- to 4-month-old C57BL/6 J, mdx, and transgenic mdx mice expressing exon 45–55-deleted human dystrophin (Tg/mdx mice) were used. We also generated two double mutant mice, mdx iNOS KO and Tg/mdx iNOS KO to reveal the iNOS contribution to RyR1 S-nitrosylation. nNOS and iNOS expression levels in skeletal muscle of these mice were assessed by immunohistochemistry (IHC), qRT-PCR, and Western blotting. Total NOS activity was measured by a citrulline assay. A biotin-switch method was used for detection of RyR1 S-nitrosylation. Statistical differences were assessed by one-way ANOVA with Tukey-Kramer post-hoc analysis. Results mdx and mdx iNOS KO mice showed the same level of RyR1 S-nitrosylation. Total NOS activity was not changed in mdx iNOS KO mice compared with mdx mice. iNOS expression was undetectable in Tg/mdx mice expressing exon 45–55-deleted human dystrophin, but the level of RyR1 S-nitrosylation was the same in mdx and Tg/mdx mice. Conclusion Similar levels of RyR1 S-nitrosylation and total NOS activity in mdx and mdx iNOS KO demonstrated that the proportion of iNOS in total NOS activity was low, even in mdx mice. Exon 45–55-deleted dystrophin reduced the expression level of iNOS, but it did not correct the RyR1 S-nitrosylation. These results indicate that iNOS was not involved in RyR1 S-nitrosylation in mdx and Tg/mdx mice muscles.
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Affiliation(s)
- Ken'ichiro Nogami
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.,Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yusuke Maruyama
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Ahmed Elhussieny
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.,Department of Neurology, Faculty of Medicine, Minia University, Minia, Egypt
| | - Fusako Sakai-Takemura
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Jun Tanihata
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.,Department of Cell Physiology, The Jikei University School of Medicine, Tokyo, Japan
| | - Jun-Ichi Kira
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yuko Miyagoe-Suzuki
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
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Truncated dystrophin ameliorates the dystrophic phenotype of mdx mice by reducing sarcolipin-mediated SERCA inhibition. Biochem Biophys Res Commun 2018; 505:51-59. [PMID: 30236982 DOI: 10.1016/j.bbrc.2018.09.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 09/07/2018] [Indexed: 11/22/2022]
Abstract
Duchenne muscular dystrophy (DMD) and the less severe Becker muscular dystrophy (BMD) are due to mutations in the DMD gene. Previous reports show that in-frame deletion of exons 45-55 produces an internally shorted, but functional, dystrophin protein resulting in a very mild BMD phenotype. In order to elucidate the molecular mechanism leading to this phenotype, we generated exon 45-55 deleted dystrophin transgenic/mdx (Tg/mdx) mice. Muscular function of Tg/mdx mice was restored close to that of wild type (WT) mice but the localization of the neuronal type of nitric oxide synthase was changed from the sarcolemma to the cytosol. This led to hyper-nitrosylation of the ryanodine receptor 1 causing increased Ca2+ release from the sarcoplasmic reticulum. On the other hand, Ca2+ reuptake by the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) was restored to the level of WT mice, suggesting that the Ca2+ dysregulation had been compensated by SERCA activation. In line with this, expression of sarcolipin (SLN), a SERCA-inhibitory peptide, was upregulated in mdx mice, but strongly reduced in Tg/mdx mice. Furthermore, knockdown of SLN ameliorated the cytosolic Ca2+ homeostasis and the dystrophic phenotype in mdx mice. These findings suggest that SLN may be a novel target for DMD therapy.
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Ohe K, Yoshida M, Nakano-Kobayashi A, Hosokawa M, Sako Y, Sakuma M, Okuno Y, Usui T, Ninomiya K, Nojima T, Kataoka N, Hagiwara M. RBM24 promotes U1 snRNP recognition of the mutated 5' splice site in the IKBKAP gene of familial dysautonomia. RNA (NEW YORK, N.Y.) 2017; 23:1393-1403. [PMID: 28592461 PMCID: PMC5558909 DOI: 10.1261/rna.059428.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/25/2017] [Indexed: 06/07/2023]
Abstract
The 5' splice site mutation (IVS20+6T>C) of the inhibitor of κ light polypeptide gene enhancer in B cells, kinase complex-associated protein (IKBKAP) gene in familial dysautonomia (FD) is at the sixth intronic nucleotide of the 5' splice site. It is known to weaken U1 snRNP recognition and result in an aberrantly spliced mRNA product in neuronal tissue, but normally spliced mRNA in other tissues. Aberrantly spliced IKBKAP mRNA abrogates IKK complex-associated protein (IKAP)/elongator protein 1 (ELP1) expression and results in a defect of neuronal cell development in FD. To elucidate the tissue-dependent regulatory mechanism, we screened an expression library of major RNA-binding proteins (RBPs) with our mammalian dual-color splicing reporter system and identified RBM24 as a regulator. RBM24 functioned as a cryptic intronic splicing enhancer binding to an element (IVS20+13-29) downstream from the intronic 5' splice site mutation in the IKBKAP gene and promoted U1 snRNP recognition only to the mutated 5' splice site (and not the wild-type 5' splice site). Our results show that tissue-specific expression of RBM24 can explain the neuron-specific aberrant splicing of IKBKAP exon 20 in familial dysautonomia, and that ectopic expression of RBM24 in neuronal tissue could be a novel therapeutic target of the disease.
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Affiliation(s)
- Kenji Ohe
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
- Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mayumi Yoshida
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Akiko Nakano-Kobayashi
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Motoyasu Hosokawa
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiya Sako
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Maki Sakuma
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiko Okuno
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Tomomi Usui
- Laboratory of Gene Expression, School of Biomedical Science, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Kensuke Ninomiya
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takayuki Nojima
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Naoyuki Kataoka
- Laboratory for Malignancy Control Research, Medical Innovation Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507, Japan
- Laboratory of Cell Regulation, Departments of Applied Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
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Moorwood C, Khurana TS. Duchenne muscular dystrophy drug discovery - the application of utrophin promoter activation screening. Expert Opin Drug Discov 2013; 8:569-81. [PMID: 23473647 DOI: 10.1517/17460441.2013.777040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Duchenne muscular dystrophy (DMD) is a devastating genetic muscle wasting disease caused by mutations in the DMD gene that in turn lead to an absence of dystrophin. Currently, there is no definitive therapy for DMD. Gene- and cell-based therapies designed to replace dystrophin have met some degree of success, as have strategies that seek to improve the dystrophic pathology independent of dystrophin. AREAS COVERED In this review the authors focus on utrophin promoter activation-based strategies and their implications on potential therapeutics for DMD. These strategies in common are designed to identify drugs/small molecules that can activate the utrophin promoter and would allow the functional substitution of dystrophin by upregulating utrophin expression in dystrophic muscle. The authors provide an overview of utrophin biology with a focus on regulation of the utrophin promoter and discuss current attempts in identifying utrophin promoter-activating molecules using high-throughput screening (HTS). EXPERT OPINION The characterisation of utrophin promoter regulatory mechanisms coupled with advances in HTS have allowed researchers to undertake screens and identify a number of promising lead compounds that may prove useful for DMD. In principle, these pharmacological compounds offer significant advantages from a translational viewpoint for developing DMD therapeutics.
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Affiliation(s)
- Catherine Moorwood
- University of Pennsylvania School of Dental Medicine, Department of Anatomy & Cell Biology, 438 Levy Research Building, 240 S. 40th Street, Philadelphia, PA 19104, USA
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Wang Q, Cao DH, Jin CL, Lin CK, Ma HW, Wu YY. A Method of Utrophin Up-Regulation through RNAi-Mediated Knockdown of the Transcription Factor EN1. J Int Med Res 2011; 39:161-71. [PMID: 21672318 DOI: 10.1177/147323001103900117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The aim of this study was to induce up-regulation of the dystrophin-related gene UTRN that encodes the protein utrophin, to determine whether this could compensate for the lack of dystrophin function in Duchenne muscular dystrophy. The human UTRN promoter, which contains two putative binding sites for homeobox protein engrailed-1 (EN1), was analysed. It was found that EN1 binding site 2 in the UTRN gene promoter directly interacted with transcription factor EN1 in vitro. Chromatin immunoprecipitation assays of the EN1– UTRN promoter complex from rhabdomyosarcoma and HeLa cell lines confirmed that endogenous EN1 interacted with this region in vivo. The findings suggest that EN1 directly interacts with the UTRN promoter. Small interfering RNA was used to inhibit EN1 gene expression. Higher utrophin mRNA levels were observed in EN1-inhibited cells compared with controls. The increase in utrophin mRNA in rhabdomyosarcoma cells and HeLa cells may have resulted from inhibition of EN1 expression.
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Affiliation(s)
- Q Wang
- Senior Profession College, China Medical University, Shenyang, China
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - D-H Cao
- Department of Laboratory Medicine, No. 202 Hospital of the People's Liberation Army, Shenyang, China
| | - C-L Jin
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - C-K Lin
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - H-W Ma
- Department of Paediatrics, Shengjing Hospital, China Medical University, Shenyang, China
| | - Y-Y Wu
- Department of Paediatrics, Shengjing Hospital, China Medical University, Shenyang, China
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Miura P, Coriati A, Bélanger G, De Repentigny Y, Lee J, Kothary R, Holcik M, Jasmin BJ. The utrophin A 5'-UTR drives cap-independent translation exclusively in skeletal muscles of transgenic mice and interacts with eEF1A2. Hum Mol Genet 2010; 19:1211-20. [PMID: 20053670 DOI: 10.1093/hmg/ddp591] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The molecular mechanisms regulating expression of utrophin A are of therapeutic interest since upregulating its expression at the sarcolemma can compensate for the lack of dystrophin in animal models of Duchenne Muscular Dystrophy (DMD). The 5'-UTR of utrophin A has been previously shown to drive cap-independent internal ribosome entry site (IRES)-mediated translation in response to muscle regeneration and glucocorticoid treatment. To determine whether the utrophin A IRES displays tissue specific activity, we generated transgenic mice harboring control (CMV/betaGAL/CAT) or utrophin A 5'-UTR (CMV/betaGAL/UtrA/CAT) bicistronic reporter transgenes. Examination of multiple tissues from two CMV/betaGAL/UtrA/CAT lines revealed that the utrophin A 5'-UTR drives cap-independent translation of the reporter gene exclusively in skeletal muscles and no other examined tissues. This expression pattern suggested that skeletal muscle-specific factors are involved in IRES-mediated translation of utrophin A. We performed RNA-affinity chromatography experiments combined with mass spectrometry to identify trans-factors that bind the utrophin A 5'-UTR and identified eukaryotic elongation factor 1A2 (eEF1A2). UV-crosslinking experiments confirmed the specificity of this interaction. Regions of the utrophin A 5'-UTR that bound eEF1A2 also mediated cap-independent translation in C2C12 muscle cells. Cultured cells lacking eEF1A2 had reduced IRES activity compared with cells overexpressing eEF1A2. Together, these results suggest an important role for eEF1A2 in driving cap-independent translation of utrophin A in skeletal muscle. The trans-factors and signaling pathways driving skeletal-muscle specific IRES-mediated translation of utrophin A could provide unique targets for developing pharmacological-based DMD therapies.
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Affiliation(s)
- P Miura
- Department of Cellular & Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
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