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Ouyang Z, Zhu H, Liu Z, Tu C, Qu J, Lu Q, Xu M. Curcumin inhibits the proliferation and migration of osteosarcoma by regulating the expression of super -enhancer -associated genes. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2024; 49:541-552. [PMID: 39019783 PMCID: PMC11255199 DOI: 10.11817/j.issn.1672-7347.2024.230224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Indexed: 07/19/2024]
Abstract
OBJECTIVES Super-enhancer-associated genes may be closely related to the progression of osteosarcoma, curcumin exhibits a certain inhibitory effect on tumors such as osteosarcoma. This study aims to investigate the effects of curcumin on osteosarcoma in vitro and in vivo, and to determine whether curcumin can inhibit the progression of osteosarcoma by suppressing the expression of super-enhancer-associated genes LIM and senescent cell antigen-like-containing domain 1 (LIMS1), secreted protein acidic and rich in cysteine (SPARC), and sterile alpha motif domain containing 4A (SAMD4A). METHODS Human osteosarcoma cell lines (MG63 cells or U2OS cells) were treated with 5 to 50 μmol/L curcumin for 24, 48, and 72 hours, followed by the methyl thiazolyl tetrazolium (MTT) assay to detect cell viability. Cells were incubated with dimethyl sulfoxide (DMSO) or curcumin (2.5, 5.0 μmol/L) for 7 days, and a colony formation assay was used to measure in vitro cell proliferation. After treatment with DMSO or curcumin (10, 15 μmol/L), a scratch healing assay and a transwell migration assay were performed to evaluate cell migration ability. Real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and Western blotting were used to detect mRNA and protein expression levels of LIMS1, SPARC, and SAMD4A in the cells. An osteosarcoma-bearing nude mouse model was established, and curcumin was administered via gavage for 14 days to assess the impact of curcumin on tumor volume and weight in vivo. Real-time RT-PCR was used to measure mRNA expression levels of LIMS1, SPARC, and SAMD4A in the cancer and adjacent tissues from 12 osteosarcoma patients. RESULTS After treating cells with different concentrations of curcumin for 24, 48, and 72 hours, cell viability were all significantly decreased. Compared with the DMSO group, the colony formation rates in the 2.5 μmol/L and 5.0 μmol/L curcumin groups significantly declined (both P<0.01). The scratch healing assay showed that, compared with the DMSO group, the migration rates of cells in the 10 μmol/L and 15 μmol/L curcumin groups were significantly reduced. The exception was the 10 μmol/L curcumin group at 24 h, where the migration rate of U2OS cells did not show a statistically significant difference (P>0.05), while all other differences were statistically significant (P<0.01 or P<0.001). The transwell migration assay results showed that the number of migrating cells in the 10 μmol/L and 15 μmol/L curcumin groups was significantly lower than that in the DMSO group (both P<0.001). In the in vivo tumor-bearing mouse experiment, the curcumin group showed a reduction in tumor mass (P<0.01) and a significant reduction in tumor volume (P<0.001) compared with the control group. Compared with the DMSO group, the mRNA expression levels of LIMS1, SPARC, and SAMD4A in the 10 μmol/L and 15 μmol/L curcumin groups were significantly down-regulated (all P<0.05). Additionally, the protein expression level of LIMS1 in U2OS cells in the 10 μmol/L curcumin group was significantly lower than that in the DMSO group (P<0.05). Compared with adjacent tissues, the mRNA expression level of SPARC in osteosarcoma tissues was significantly increased (P<0.001), while the mRNA expression levels of LIMS1 and SAMD4A did not show statistically significant differences (both P>0.05). CONCLUSIONS Curcumin inhibits the proliferation and migration of osteosarcoma both in vitro and in vivo, which may be associated with the inactivation of super-enhancer-associated gene LIMS1.
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Affiliation(s)
- Zhanbo Ouyang
- Department of Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011.
- Institute of Clinical Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011.
- Department of Pharmacy, Yueyang Central Hospital, Yueyang Hunan 414000.
| | - Haihong Zhu
- Department of Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Clinical Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
| | - Zhongyue Liu
- Department of Orthopaedics, Second Xiangya Hospital, Central South University, Changsha 410011
| | - Chao Tu
- Department of Orthopaedics, Second Xiangya Hospital, Central South University, Changsha 410011
| | - Jian Qu
- Department of Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Clinical Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
| | - Qiong Lu
- Department of Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
- Institute of Clinical Pharmacy, Second Xiangya Hospital, Central South University, Changsha 410011
| | - Min Xu
- Department of Critical Care Medicine, Second Xiangya Hospital, Central South University, Changsha 410011, China.
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Engquist EN, Greco A, Joosten LAB, van Engelen BGM, Zammit PS, Banerji CRS. FSHD muscle shows perturbation in fibroadipogenic progenitor cells, mitochondrial function and alternative splicing independently of inflammation. Hum Mol Genet 2024; 33:182-197. [PMID: 37856562 PMCID: PMC10772042 DOI: 10.1093/hmg/ddad175] [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: 04/13/2023] [Revised: 09/25/2023] [Accepted: 10/10/2023] [Indexed: 10/21/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is a prevalent, incurable myopathy. FSHD is highly heterogeneous, with patients following a variety of clinical trajectories, complicating clinical trials. Skeletal muscle in FSHD undergoes fibrosis and fatty replacement that can be accelerated by inflammation, adding to heterogeneity. Well controlled molecular studies are thus essential to both categorize FSHD patients into distinct subtypes and understand pathomechanisms. Here, we further analyzed RNA-sequencing data from 24 FSHD patients, each of whom donated a biopsy from both a non-inflamed (TIRM-) and inflamed (TIRM+) muscle, and 15 FSHD patients who donated peripheral blood mononucleated cells (PBMCs), alongside non-affected control individuals. Differential gene expression analysis identified suppression of mitochondrial biogenesis and up-regulation of fibroadipogenic progenitor (FAP) gene expression in FSHD muscle, which was particularly marked on inflamed samples. PBMCs demonstrated suppression of antigen presentation in FSHD. Gene expression deconvolution revealed FAP expansion as a consistent feature of FSHD muscle, via meta-analysis of 7 independent transcriptomic datasets. Clustering of muscle biopsies separated patients in an unbiased manner into clinically mild and severe subtypes, independently of known disease modifiers (age, sex, D4Z4 repeat length). Lastly, the first genome-wide analysis of alternative splicing in FSHD muscle revealed perturbation of autophagy, BMP2 and HMGB1 signalling. Overall, our findings reveal molecular subtypes of FSHD with clinical relevance and identify novel pathomechanisms for this highly heterogeneous condition.
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Affiliation(s)
- Elise N Engquist
- Randall Centre for Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, United Kingdom
| | - Anna Greco
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
- Department of Internal Medicine, Radboud Institute of Molecular Life Sciences (RIMLS) and Radboud Center of Infectious Diseases (RCI), Radboud University Medical Center, Geert Grooteplein Zuid 10, Nijmegen 6525 GA, The Netherlands
| | - Leo A B Joosten
- Department of Internal Medicine, Radboud Institute of Molecular Life Sciences (RIMLS) and Radboud Center of Infectious Diseases (RCI), Radboud University Medical Center, Geert Grooteplein Zuid 10, Nijmegen 6525 GA, The Netherlands
- Department of Medical Genetics, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania
| | - Baziel G M van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Peter S Zammit
- Randall Centre for Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, United Kingdom
| | - Christopher R S Banerji
- Randall Centre for Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, United Kingdom
- The Alan Turing Institute, The British Library, 96 Euston Road, London NW1 2DB, United Kingdom
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Souidi A, Nakamori M, Zmojdzian M, Jagla T, Renaud Y, Jagla K. Deregulations of miR-1 and its target Multiplexin promote dilated cardiomyopathy associated with myotonic dystrophy type 1. EMBO Rep 2023; 24:e56616. [PMID: 36852954 PMCID: PMC10074075 DOI: 10.15252/embr.202256616] [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: 12/06/2022] [Revised: 02/03/2023] [Accepted: 02/14/2023] [Indexed: 03/01/2023] Open
Abstract
Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy in adults. It is caused by the excessive expansion of noncoding CTG repeats, which when transcribed affects the functions of RNA-binding factors with adverse effects on alternative splicing, processing, and stability of a large set of muscular and cardiac transcripts. Among these effects, inefficient processing and down-regulation of muscle- and heart-specific miRNA, miR-1, have been reported in DM1 patients, but the impact of reduced miR-1 on DM1 pathogenesis has been unknown. Here, we use Drosophila DM1 models to explore the role of miR-1 in cardiac dysfunction in DM1. We show that miR-1 down-regulation in the heart leads to dilated cardiomyopathy (DCM), a DM1-associated phenotype. We combined in silico screening for miR-1 targets with transcriptional profiling of DM1 cardiac cells to identify miR-1 target genes with potential roles in DCM. We identify Multiplexin (Mp) as a new cardiac miR-1 target involved in DM1. Mp encodes a collagen protein involved in cardiac tube formation in Drosophila. Mp and its human ortholog Col15A1 are both highly enriched in cardiac cells of DCM-developing DM1 flies and in heart samples from DM1 patients with DCM, respectively. When overexpressed in the heart, Mp induces DCM, whereas its attenuation rescues the DCM phenotype of aged DM1 flies. Reduced levels of miR-1 and consecutive up-regulation of its target Mp/Col15A1 might be critical in DM1-associated DCM.
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Affiliation(s)
- Anissa Souidi
- iGReD Genetics Reproduction and Development Institute, Clermont Auvergne University, Clermont-Ferrand, France
| | - Masayuki Nakamori
- Department of Neurology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Monika Zmojdzian
- iGReD Genetics Reproduction and Development Institute, Clermont Auvergne University, Clermont-Ferrand, France
| | - Teresa Jagla
- iGReD Genetics Reproduction and Development Institute, Clermont Auvergne University, Clermont-Ferrand, France
| | - Yoan Renaud
- iGReD Genetics Reproduction and Development Institute, Clermont Auvergne University, Clermont-Ferrand, France
| | - Krzysztof Jagla
- iGReD Genetics Reproduction and Development Institute, Clermont Auvergne University, Clermont-Ferrand, France
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Wang XY, Zhang LN. RNA binding protein SAMD4: current knowledge and future perspectives. Cell Biosci 2023; 13:21. [PMID: 36732864 PMCID: PMC9893680 DOI: 10.1186/s13578-023-00968-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/22/2023] [Indexed: 02/04/2023] Open
Abstract
SAMD4 protein family is a class of novel RNA-binding proteins that can mediate post-transcriptional regulation and translation repression in eukaryotes, which are highly conserved from yeast to humans during evolution. In mammalian cells, SAMD4 protein family consists of two members including SAMD4A/Smaug1 and SAMD4B/Smaug2, both of which contain common SAM domain that can specifically bind to different target mRNAs through stem-loop structures, also known as Smaug recognition elements (SREs), and regulate the mRNA stability, degradation and translation. In addition, SAMD4 can form the cytoplasmic mRNA silencing foci and regulate the translation of SRE-containing mRNAs in neurons. SAMD4 also can form the cytosolic membrane-less organelles (MLOs), termed as Smaug1 bodies, and regulate mitochondrial function. Importantly, many studies have identified that SAMD4 family members are involved in various pathological processes including myopathy, bone development, neural development, and cancer occurrence and progression. In this review, we mainly summarize the structural characteristics, biological functions and molecular regulatory mechanisms of SAMD4 protein family members, which will provide a basis for further research and clinical application of SAMD4 protein family.
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Affiliation(s)
- Xin-Ya Wang
- grid.28703.3e0000 0000 9040 3743Beijing International Science and Technology Cooperation Base of Antivirus Drug, Faculty of Environment and Life, Beijing University of Technology, 100124 Beijing, People’s Republic of China
| | - Li-Na Zhang
- grid.28703.3e0000 0000 9040 3743Beijing International Science and Technology Cooperation Base of Antivirus Drug, Faculty of Environment and Life, Beijing University of Technology, 100124 Beijing, People’s Republic of China
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5
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In heart failure reactivation of RNA-binding proteins is associated with the expression of 1,523 fetal-specific isoforms. PLoS Comput Biol 2022; 18:e1009918. [PMID: 35226669 PMCID: PMC8912908 DOI: 10.1371/journal.pcbi.1009918] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 03/10/2022] [Accepted: 02/10/2022] [Indexed: 01/03/2023] Open
Abstract
Reactivation of fetal-specific genes and isoforms occurs during heart failure. However, the underlying molecular mechanisms and the extent to which the fetal program switch occurs remains unclear. Limitations hindering transcriptome-wide analyses of alternative splicing differences (i.e. isoform switching) in cardiovascular system (CVS) tissues between fetal, healthy adult and heart failure have included both cellular heterogeneity across bulk RNA-seq samples and limited availability of fetal tissue for research. To overcome these limitations, we have deconvoluted the cellular compositions of 996 RNA-seq samples representing heart failure, healthy adult (heart and arteria), and fetal-like (iPSC-derived cardiovascular progenitor cells) CVS tissues. Comparison of the expression profiles revealed that reactivation of fetal-specific RNA-binding proteins (RBPs), and the accompanied re-expression of 1,523 fetal-specific isoforms, contribute to the transcriptome differences between heart failure and healthy adult heart. Of note, isoforms for 20 different RBPs were among those that reverted in heart failure to the fetal-like expression pattern. We determined that, compared with adult-specific isoforms, fetal-specific isoforms encode proteins that tend to have more functions, are more likely to harbor RBP binding sites, have canonical sequences at their splice sites, and contain typical upstream polypyrimidine tracts. Our study suggests that compared with healthy adult, fetal cardiac tissue requires stricter transcriptional regulation, and that during heart failure reversion to this stricter transcriptional regulation occurs. Furthermore, we provide a resource of cardiac developmental stage-specific and heart failure-associated genes and isoforms, which are largely unexplored and can be exploited to investigate novel therapeutics for heart failure. Heart failure is a chronic condition in which the heart does not pump enough blood. It has been shown that in heart failure, the adult heart reverts to a fetal-like metabolic state and oxygen consumption. Additionally, genes and isoforms that are expressed in the heart only during fetal development (i.e. not in the healthy adult heart) are turned on in heart failure. However, the underlying molecular mechanisms and the extent to which the switch to a fetal gene program occurs remains unclear. In this study, we initially characterized the differences between the fetal and adult heart transcriptomes (entire set of expressed genes and isoforms). We found that RNA binding proteins (RBPs), a family of genes that regulate multiple aspects of a transcript’s maturation, including transcription, splicing and post-transcriptional modifications, play a central role in the differences between fetal and adult heart tissues. We observed that many RBPs that are only expressed in the heart during fetal development become reactivated in heart failure, resulting in the expression of 1,523 fetal-specific isoforms. These findings suggest that reactivation of fetal-specific RBPs in heart failure drives a transcriptome-wide switch to expression of fetal-specific isoforms; and hence that RBPs could potentially serve as novel therapeutic targets.
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6
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Fernández-Alvarez AJ, Thomas MG, Pascual ML, Habif M, Pimentel J, Corbat AA, Pessoa JP, La Spina PE, Boscaglia L, Plessis A, Carmo-Fonseca M, Grecco HE, Casado M, Boccaccio GL. Smaug1 membrane-less organelles respond to AMPK/mTOR and affect mitochondrial function‡. J Cell Sci 2021; 135:273619. [PMID: 34859817 DOI: 10.1242/jcs.253591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 11/15/2021] [Indexed: 11/20/2022] Open
Abstract
Smaug is a conserved translational regulator that binds numerous mRNAs, including nuclear transcripts that encode mitochondrial enzymes. Smaug orthologs form cytosolic membrane-less organelles (MLOs) in several organisms and cell types. We have performed single-molecule FISH assays that revealed that SDHB and UQCRC1 mRNAs associate with Smaug1 bodies in U2OS cells. Loss of function of Smaug1 and Smaug2 affected both mitochondrial respiration and morphology of the mitochondrial network. Phenotype rescue by Smaug1 transfection depends on the presence of its RNA binding domain. Moreover, we identified specific Smaug1 domains involved in MLO formation, and found that impaired Smaug1 MLO condensation correlates with mitochondrial defects. Mitochondrial Complex I inhibition by rotenone -but not strong mitochondrial uncoupling by CCCP- rapidly induced Smaug1 MLOs dissolution. Metformin and rapamycin elicited similar effects, which were blocked by pharmacological inhibition of AMPK. Finally, we found that Smaug1 MLO dissolution weakens the interaction with target mRNAs, thus enabling their release. We propose that mitochondrial respiration and the AMPK/mTOR balance controls the condensation and dissolution of Smaug1 MLOs, thus regulating nuclear mRNAs that encode key mitochondrial proteins.
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Affiliation(s)
- Ana J Fernández-Alvarez
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - María Gabriela Thomas
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Malena L Pascual
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Martín Habif
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - Jerónimo Pimentel
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Agustín A Corbat
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - João P Pessoa
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Pablo E La Spina
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | | | - Anne Plessis
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, F-75205 Paris, France
| | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Hernán E Grecco
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - Marta Casado
- Instituto de Biomedicina de Valencia, IBV-CSIC, Valencia 46010, Spain, and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid 28029, Spain
| | - Graciela L Boccaccio
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina.,Department of Molecular and Cellular Biology and Physiology (FBMyC), Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, C1428EHA Buenos Aires, Argentina
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Alexander MS, Hightower RM, Reid AL, Bennett AH, Iyer L, Slonim DK, Saha M, Kawahara G, Kunkel LM, Kopin AS, Gupta VA, Kang PB, Draper I. hnRNP L is essential for myogenic differentiation and modulates myotonic dystrophy pathologies. Muscle Nerve 2021; 63:928-940. [PMID: 33651408 DOI: 10.1002/mus.27216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 02/25/2021] [Accepted: 02/28/2021] [Indexed: 12/12/2022]
Abstract
INTRODUCTION RNA-binding proteins (RBPs) play an important role in skeletal muscle development and disease by regulating RNA splicing. In myotonic dystrophy type 1 (DM1), the RBP MBNL1 (muscleblind-like) is sequestered by toxic CUG repeats, leading to missplicing of MBNL1 targets. Mounting evidence from the literature has implicated other factors in the pathogenesis of DM1. Herein we sought to evaluate the functional role of the splicing factor hnRNP L in normal and DM1 muscle cells. METHODS Co-immunoprecipitation assays using hnRNPL and MBNL1 expression constructs and splicing profiling in normal and DM1 muscle cell lines were performed. Zebrafish morpholinos targeting hnrpl and hnrnpl2 were injected into one-cell zebrafish for developmental and muscle analysis. In human myoblasts downregulation of hnRNP L was achieved with shRNAi. Ascochlorin administration to DM1 myoblasts was performed and expression of the CUG repeats, DM1 splicing biomarkers, and hnRNP L expression levels were evaluated. RESULTS Using DM1 patient myoblast cell lines we observed the formation of abnormal hnRNP L nuclear foci within and outside the expanded CUG repeats, suggesting a role for this factor in DM1 pathology. We showed that the antiviral and antitumorigenic isoprenoid compound ascochlorin increased MBNL1 and hnRNP L expression levels. Drug treatment of DM1 muscle cells with ascochlorin partially rescued missplicing of established early biomarkers of DM1 and improved the defective myotube formation displayed by DM1 muscle cells. DISCUSSION Together, these studies revealed that hnRNP L can modulate DM1 pathologies and is a potential therapeutic target.
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Affiliation(s)
- Matthew S Alexander
- Division of Neurology, Department of Pediatrics, University of Alabama at Birmingham and Children's of Alabama, Birmingham, Alabama, USA.,Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Civitan International Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Rylie M Hightower
- Division of Neurology, Department of Pediatrics, University of Alabama at Birmingham and Children's of Alabama, Birmingham, Alabama, USA.,Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Andrea L Reid
- Division of Neurology, Department of Pediatrics, University of Alabama at Birmingham and Children's of Alabama, Birmingham, Alabama, USA
| | - Alexis H Bennett
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Lakshmanan Iyer
- Department of Neuroscience, Tufts University, Boston, Massachusetts, USA
| | - Donna K Slonim
- Department of Computer Science, Tufts University, Medford, Massachusetts, USA
| | - Madhurima Saha
- Division of Pediatric Neurology, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Genri Kawahara
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Louis M Kunkel
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts, USA.,Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA.,Harvard Stem Cell Institute, Cambridge, Massachusetts, USA.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Alan S Kopin
- Department of Medicine, Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts, USA
| | - Vandana A Gupta
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Peter B Kang
- Division of Pediatric Neurology, Department of Pediatrics, University of Florida College of Medicine, Gainesville, Florida, USA.,Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, Florida, USA.,Department of Neurology, University of Florida College of Medicine, Gainesville, Florida, USA.,Genetics Institute and Myology Institute, University of Florida, Gainesville, Florida, USA.,Paul and Sheila Wellstone Muscular Dystrophy Center, University of Minnesota Medical School, Minneapolis, Minnesota, USA.,Neurology Department, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Isabelle Draper
- Department of Medicine, Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts, USA
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8
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Bruzzone L, Argüelles C, Sanial M, Miled S, Alvisi G, Gonçalves-Antunes M, Qasrawi F, Holmgren RA, Smibert CA, Lipshitz HD, Boccaccio GL, Plessis A, Bécam I. Regulation of the RNA-binding protein Smaug by the GPCR Smoothened via the kinase Fused. EMBO Rep 2020; 21:e48425. [PMID: 32383557 DOI: 10.15252/embr.201948425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 03/17/2020] [Accepted: 04/14/2020] [Indexed: 12/13/2022] Open
Abstract
From fly to mammals, the Smaug/Samd4 family of prion-like RNA-binding proteins control gene expression by destabilizing and/or repressing the translation of numerous target transcripts. However, the regulation of its activity remains poorly understood. We show that Smaug's protein levels and mRNA repressive activity are downregulated by Hedgehog signaling in tissue culture cells. These effects rely on the interaction of Smaug with the G-protein coupled receptor Smoothened, which promotes the phosphorylation of Smaug by recruiting the kinase Fused. The activation of Fused and its binding to Smaug are sufficient to suppress its ability to form cytosolic bodies and to antagonize its negative effects on endogenous targets. Importantly, we demonstrate in vivo that HH reduces the levels of smaug mRNA and increases the level of several mRNAs downregulated by Smaug. Finally, we show that Smaug acts as a positive regulator of Hedgehog signaling during wing morphogenesis. These data constitute the first evidence for a post-translational regulation of Smaug and reveal that the fate of several mRNAs bound to Smaug is modulated by a major signaling pathway.
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Affiliation(s)
- Lucia Bruzzone
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Matthieu Sanial
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Samia Miled
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Giorgia Alvisi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Fairouz Qasrawi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Robert A Holmgren
- Department of Mol. Biosci., Northwestern University, Evanston, IL, USA
| | - Craig A Smibert
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Graciela L Boccaccio
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Anne Plessis
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Isabelle Bécam
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
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SAMD4 family members suppress human hepatitis B virus by directly binding to the Smaug recognition region of viral RNA. Cell Mol Immunol 2020; 18:1032-1044. [PMID: 32341522 PMCID: PMC7223975 DOI: 10.1038/s41423-020-0431-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 03/26/2020] [Indexed: 12/16/2022] Open
Abstract
HBV infection initiates hepatitis B and promotes liver cirrhosis and hepatocellular carcinoma. IFN-α is commonly used in hepatitis B therapy, but how it inhibits HBV is not fully understood. We screened 285 human interferon-stimulated genes (ISGs) for anti-HBV activity using a cell-based assay, which revealed several anti-HBV ISGs. Among these ISGs, SAMD4A was the strongest suppressor of HBV replication. We found the binding site of SAMD4A in HBV RNA, which was a previously unidentified Smaug recognition region (SRE) sequence conserved in HBV variants. SAMD4A binds to the SRE site in viral RNA to trigger its degradation. The SAM domain in SAMD4A is critical for RNA binding and the C-terminal domain of SAMD4A is required for SAMD4A anti-HBV function. Human SAMD4B is a homolog of human SAMD4A but is not an ISG, and the murine genome encodes SAMD4. All these SAMD4 proteins suppressed HBV replication when overexpressed in vitro and in vivo. We also showed that knocking out the Samd4 gene in hepatocytes led to a higher level of HBV replication in mice and AAV-delivered SAMD4A expression reduced the virus titer in HBV-producing transgenic mice. In addition, a database analysis revealed a negative correlation between the levels of SAMD4A/B and HBV in patients. Our data suggest that SAMD4A is an important anti-HBV ISG for use in IFN therapy of hepatitis B and that the levels of SAMD4A/B expression are related to HBV sensitivity in humans.
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10
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Pandey PR, Yang JH, Tsitsipatis D, Panda AC, Noh JH, Kim KM, Munk R, Nicholson T, Hanniford D, Argibay D, Yang X, Martindale JL, Chang MW, Jones SW, Hernando E, Sen P, De S, Abdelmohsen K, Gorospe M. circSamd4 represses myogenic transcriptional activity of PUR proteins. Nucleic Acids Res 2020; 48:3789-3805. [PMID: 31980816 PMCID: PMC7144931 DOI: 10.1093/nar/gkaa035] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 01/06/2020] [Accepted: 01/13/2020] [Indexed: 02/02/2023] Open
Abstract
By interacting with proteins and nucleic acids, the vast family of mammalian circRNAs is proposed to influence many biological processes. Here, RNA sequencing analysis of circRNAs differentially expressed during myogenesis revealed that circSamd4 expression increased robustly in mouse C2C12 myoblasts differentiating into myotubes. Moreover, silencing circSamd4, which is conserved between human and mouse, delayed myogenesis and lowered the expression of myogenic markers in cultured myoblasts from both species. Affinity pulldown followed by mass spectrometry revealed that circSamd4 associated with PURA and PURB, two repressors of myogenesis that inhibit transcription of the myosin heavy chain (MHC) protein family. Supporting the hypothesis that circSamd4 might complex with PUR proteins and thereby prevent their interaction with DNA, silencing circSamd4 enhanced the association of PUR proteins with the Mhc promoter, while overexpressing circSamd4 interfered with the binding of PUR proteins to the Mhc promoter. These effects were abrogated when using a mutant circSamd4 lacking the PUR binding site. Our results indicate that the association of PUR proteins with circSamd4 enhances myogenesis by contributing to the derepression of MHC transcription.
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Affiliation(s)
- Poonam R Pandey
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Jen-Hao Yang
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Dimitrios Tsitsipatis
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Amaresh C Panda
- Institute of Life Sciences, Nalco Square, Bhubaneswar, Odisha, India
| | - Ji Heon Noh
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
- Department of Biotechnology, Chonnam National University, Yeosu, Chonnam, Republic of Korea
| | - Kyoung Mi Kim
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
- Department of Biological Sciences, Chungnam National University, Daejeon, Republic of Korea
| | - Rachel Munk
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Thomas Nicholson
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, UK
| | - Douglas Hanniford
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Diana Argibay
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Xiaoling Yang
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Jennifer L Martindale
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Ming-Wen Chang
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Simon W Jones
- Institute of Inflammation and Ageing, MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, UK
| | - Eva Hernando
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Payel Sen
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Supriyo De
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Kotb Abdelmohsen
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
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11
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Nikonova E, Kao SY, Ravichandran K, Wittner A, Spletter ML. Conserved functions of RNA-binding proteins in muscle. Int J Biochem Cell Biol 2019; 110:29-49. [PMID: 30818081 DOI: 10.1016/j.biocel.2019.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 02/21/2019] [Accepted: 02/23/2019] [Indexed: 12/13/2022]
Abstract
Animals require different types of muscle for survival, for example for circulation, motility, reproduction and digestion. Much emphasis in the muscle field has been placed on understanding how transcriptional regulation generates diverse types of muscle during development. Recent work indicates that alternative splicing and RNA regulation are as critical to muscle development, and altered function of RNA-binding proteins causes muscle disease. Although hundreds of genes predicted to bind RNA are expressed in muscles, many fewer have been functionally characterized. We present a cross-species view summarizing what is known about RNA-binding protein function in muscle, from worms and flies to zebrafish, mice and humans. In particular, we focus on alternative splicing regulated by the CELF, MBNL and RBFOX families of proteins. We discuss the systemic nature of diseases associated with loss of RNA-binding proteins in muscle, focusing on mis-regulation of CELF and MBNL in myotonic dystrophy. These examples illustrate the conservation of RNA-binding protein function and the marked utility of genetic model systems in understanding mechanisms of RNA regulation.
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Affiliation(s)
- Elena Nikonova
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Shao-Yen Kao
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Keshika Ravichandran
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Anja Wittner
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Maria L Spletter
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany; Center for Integrated Protein Science Munich (CIPSM) at the Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany.
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12
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Souidi A, Zmojdzian M, Jagla K. Dissecting Pathogenetic Mechanisms and Therapeutic Strategies in Drosophila Models of Myotonic Dystrophy Type 1. Int J Mol Sci 2018; 19:E4104. [PMID: 30567354 PMCID: PMC6321436 DOI: 10.3390/ijms19124104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 12/08/2018] [Accepted: 12/13/2018] [Indexed: 12/16/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1), the most common cause of adult-onset muscular dystrophy, is autosomal dominant, multisystemic disease with characteristic symptoms including myotonia, heart defects, cataracts and testicular atrophy. DM1 disease is being successfully modelled in Drosophila allowing to identify and validate new pathogenic mechanisms and potential therapeutic strategies. Here we provide an overview of insights gained from fruit fly DM1 models, either: (i) fundamental with particular focus on newly identified gene deregulations and their link with DM1 symptoms; or (ii) applied via genetic modifiers and drug screens to identify promising therapeutic targets.
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Affiliation(s)
- Anissa Souidi
- GReD, INSERM U1103, CNRS, UMR6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France.
| | - Monika Zmojdzian
- GReD, INSERM U1103, CNRS, UMR6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France.
| | - Krzysztof Jagla
- GReD, INSERM U1103, CNRS, UMR6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France.
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13
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Ueyama M, Nagai Y. Repeat Expansion Disease Models. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1076:63-78. [PMID: 29951815 DOI: 10.1007/978-981-13-0529-0_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Repeat expansion disorders are a group of inherited neuromuscular diseases, which are caused by expansion mutations of repeat sequences in the disease-causing genes. Repeat expansion disorders include a class of diseases caused by repeat expansions in the coding region of the genes, producing mutant proteins with amino acid repeats, mostly the polyglutamine (polyQ) diseases, and another class of diseases caused by repeat expansions in the noncoding regions, producing aberrant RNA with expanded repeats, which are called noncoding repeat expansion diseases. A variety of Drosophila disease models have been established for both types of diseases, and they have made significant contributions toward elucidating the molecular mechanisms of and developing therapies for these neuromuscular diseases.
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Affiliation(s)
- Morio Ueyama
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yoshitaka Nagai
- Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Osaka, Japan.
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14
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Picchio L, Legagneux V, Deschamps S, Renaud Y, Chauveau S, Paillard L, Jagla K. Bruno-3 regulates sarcomere component expression and contributes to muscle phenotypes of myotonic dystrophy type 1. Dis Model Mech 2018; 11:dmm.031849. [PMID: 29716962 PMCID: PMC5992612 DOI: 10.1242/dmm.031849] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 04/18/2018] [Indexed: 01/22/2023] Open
Abstract
Steinert disease, or myotonic dystrophy type 1 (DM1), is a multisystemic disorder caused by toxic noncoding CUG repeat transcripts, leading to altered levels of two RNA binding factors, MBNL1 and CELF1. The contribution of CELF1 to DM1 phenotypes is controversial. Here, we show that the Drosophila CELF1 family member, Bru-3, contributes to pathogenic muscle defects observed in a Drosophila model of DM1. Bru-3 displays predominantly cytoplasmic expression in muscles and its muscle-specific overexpression causes a range of phenotypes also observed in the fly DM1 model, including affected motility, fiber splitting, reduced myofiber length and altered myoblast fusion. Interestingly, comparative genome-wide transcriptomic analyses revealed that Bru-3 negatively regulates levels of mRNAs encoding a set of sarcomere components, including Actn transcripts. Conversely, it acts as a positive regulator of Actn translation. As CELF1 displays predominantly cytoplasmic expression in differentiating C2C12 myotubes and binds to Actn mRNA, we hypothesize that it might exert analogous functions in vertebrate muscles. Altogether, we propose that cytoplasmic Bru-3 contributes to DM1 pathogenesis in a Drosophila model by regulating sarcomeric transcripts and protein levels.
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Affiliation(s)
- Lucie Picchio
- GReD (Genetics, Reproduction and Development Laboratory), INSERM 1103, CNRS 6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Vincent Legagneux
- IGDR (Institut de Génétique et Développement de Rennes), UMR 6290 CNRS, Université de Rennes, 2 Avenue Léon Bernard, 35000 Rennes, France.,Inserm UMR1085 IRSET, Université de Rennes 1, 35000 Rennes, France.,CNRS-Université de Rennes1-INRIA, UMR6074 IRISA, 35000 Rennes, France
| | - Stephane Deschamps
- IGDR (Institut de Génétique et Développement de Rennes), UMR 6290 CNRS, Université de Rennes, 2 Avenue Léon Bernard, 35000 Rennes, France
| | - Yoan Renaud
- GReD (Genetics, Reproduction and Development Laboratory), INSERM 1103, CNRS 6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Sabine Chauveau
- GReD (Genetics, Reproduction and Development Laboratory), INSERM 1103, CNRS 6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Luc Paillard
- IGDR (Institut de Génétique et Développement de Rennes), UMR 6290 CNRS, Université de Rennes, 2 Avenue Léon Bernard, 35000 Rennes, France
| | - Krzysztof Jagla
- GReD (Genetics, Reproduction and Development Laboratory), INSERM 1103, CNRS 6293, University of Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
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15
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Januchowski R, Sterzyńska K, Zawierucha P, Ruciński M, Świerczewska M, Partyka M, Bednarek-Rajewska K, Brązert M, Nowicki M, Zabel M, Klejewski A. Microarray-based detection and expression analysis of new genes associated with drug resistance in ovarian cancer cell lines. Oncotarget 2017; 8:49944-49958. [PMID: 28611294 PMCID: PMC5564819 DOI: 10.18632/oncotarget.18278] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 04/24/2017] [Indexed: 12/24/2022] Open
Abstract
PURPOSE The present study is to discover a new genes associated with drug resistance development in ovarian cancer. METHODS We used microarray analysis to determine alterations in the level of expression of genes in cisplatin- (CisPt), doxorubicin- (Dox), topotecan- (Top), and paclitaxel- (Pac) resistant variants of W1 and A2780 ovarian cancer cell lines. Immunohistochemistry assay was used to determine protein expression in ovarian cancer patients. RESULTS We observed alterations in the expression of 22 genes that were common to all three cell lines that were resistant to the same cytostatic drug. The level of expression of 13 genes was upregulated and that of nine genes was downregulated. In the CisPt-resistant cell line, we observed downregulated expression of ABCC6, BST2, ERAP2 and MCTP1; in the Pac-resistant cell line, we observe upregulated expression of ABCB1, EPHA7 and RUNDC3B and downregulated expression of LIPG, MCTP1, NSBP1, PCDH9, PTPRK and SEMA3A. The expression levels of three genes, ABCB1, ABCB4 and IFI16, were upregulated in the Dox-resistant cell lines. In the Top-resistant cell lines, we observed increased expression levels of ABCG2, HERC5, IFIH1, MYOT, S100A3, SAMD4A, SPP1 and TGFBI and decreased expression levels of MCTP1 and PTPRK. The expression of EPHA7, IFI16, SPP1 and TGFBI was confirmed at protein level in analyzed ovarian cancer patients.. CONCLUSIONS The expression profiles of the investigated cell lines indicated that new candidate genes are related to the development of resistance to the cytostatic drugs that are used in first- and second-line chemotherapy of ovarian cancer.
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Affiliation(s)
- Radosław Januchowski
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Karolina Sterzyńska
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Piotr Zawierucha
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
- Department of Anatomy, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Marcin Ruciński
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Monika Świerczewska
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Małgorzata Partyka
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | | | - Maciej Brązert
- Division of Infertility and Reproductive Endocrinology, Department of Gynecology, Obstetrics and Gynecological Oncology, Poznań University of Medical Sciences, Poznań, 60-535, Poland
| | - Michał Nowicki
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Maciej Zabel
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
- Department of Histology and Embryology, Wrocław Medical University, Wrocław, 50-368, Poland
| | - Andrzej Klejewski
- Department of Nursing, Poznań University of Medical Sciences, Poznań, 60-179, Poland
- Departament of Obstetrics and Womens Dieseases, Poznań University of Medical Sciences, Poznań, 60-535, Poland
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16
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Koon AC, Chan HYE. Drosophila melanogaster As a Model Organism to Study RNA Toxicity of Repeat Expansion-Associated Neurodegenerative and Neuromuscular Diseases. Front Cell Neurosci 2017; 11:70. [PMID: 28377694 PMCID: PMC5359753 DOI: 10.3389/fncel.2017.00070] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 02/27/2017] [Indexed: 12/14/2022] Open
Abstract
For nearly a century, the fruit fly, Drosophila melanogaster, has proven to be a valuable tool in our understanding of fundamental biological processes, and has empowered our discoveries, particularly in the field of neuroscience. In recent years, Drosophila has emerged as a model organism for human neurodegenerative and neuromuscular disorders. In this review, we highlight a number of recent studies that utilized the Drosophila model to study repeat-expansion associated diseases (READs), such as polyglutamine diseases, fragile X-associated tremor/ataxia syndrome (FXTAS), myotonic dystrophy type 1 (DM1) and type 2 (DM2), and C9ORF72-associated amyotrophic lateral sclerosis/frontotemporal dementia (C9-ALS/FTD). Discoveries regarding the possible mechanisms of RNA toxicity will be focused here. These studies demonstrate Drosophila as an excellent in vivo model system that can reveal novel mechanistic insights into human disorders, providing the foundation for translational research and therapeutic development.
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Affiliation(s)
- Alex C Koon
- Laboratory of Drosophila ResearchHong Kong, Hong Kong; Biochemistry ProgramHong Kong, Hong Kong
| | - Ho Yin Edwin Chan
- Laboratory of Drosophila ResearchHong Kong, Hong Kong; Biochemistry ProgramHong Kong, Hong Kong; Cell and Molecular Biology ProgramHong Kong, Hong Kong; Molecular Biotechnology Program, Faculty of Science, School of Life SciencesHong Kong, Hong Kong; School of Life Sciences, Gerald Choa Neuroscience Centre, The Chinese University of Hong KongHong Kong, Hong Kong
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17
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RNA-binding protein SAMD4 regulates skeleton development through translational inhibition of Mig6 expression. Cell Discov 2017; 3:16050. [PMID: 28163927 PMCID: PMC5259697 DOI: 10.1038/celldisc.2016.50] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 12/05/2016] [Indexed: 12/11/2022] Open
Abstract
Protein translation regulation has essential roles in inflammatory responses, cancer initiation and the pathogenesis of several neurodegenerative disorders. However, the role of the regulation of protein translation in mammalian skeleton development has been rarely elaborated. Here we report that the lack of the RNA-binding protein sterile alpha motif domain containing protein 4 (SAMD4) resulted in multiple developmental defects in mice, including delayed bone development and decreased osteogenesis. Samd4-deficient mesenchymal progenitors exhibit impaired osteoblast differentiation and function. Mechanism study demonstrates that SAMD4 binds the Mig6 mRNA and inhibits MIG6 protein synthesis. Consistent with this, Samd4-deficient cells have increased MIG6 protein level and knockdown of Mig6 rescues the impaired osteogenesis in Samd4-deficient cells. Furthermore, Samd4-deficient mice also display chondrocyte defects, which is consistent with the regulation of MIG6 protein level by SAMD4. These findings define SAMD4 as a previously unreported key regulator of osteoblastogenesis and bone development, implying that regulation of protein translation is an important mechanism governing skeletogenesis and that control of protein translation could have therapeutic potential in metabolic bone diseases, such as osteoporosis.
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18
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Fernández-Alvarez AJ, Pascual ML, Boccaccio GL, Thomas MG. Smaug variants in neural and non-neuronal cells. Commun Integr Biol 2016; 9:e1139252. [PMID: 27195061 PMCID: PMC4857778 DOI: 10.1080/19420889.2016.1139252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/02/2016] [Accepted: 01/04/2016] [Indexed: 10/25/2022] Open
Abstract
Mammalian Smaug1/Samd4a is an mRNA regulator involved in synapse plasticity and additional non-neuronal functions. Here we analyzed the expression of Smaug1/Samd4a variants and Smaug2/Samd4b in primary hippocampal neurons and non-neuronal cell lines. We found that multiple Smaug proteins are present in several mammalian cell lines, including a canonical full length Smaug1, a Smaug1 variant that lacks the third exon, termed ΔEIII, and Smaug2, the product of a highly homologous gene. These three major isoforms are expressed differentially along neuron development and form cytosolic bodies when transfected in cell lines. By using luciferase reporters, we found that the ΔEIII isoform, which lacks 10 amino acids in the sterile α motif involved in RNA binding, shows a RNA-binding capacity and repressor activity comparable to that of the full length Smaug1. These observations are an important groundwork for molecular studies of the Smaug post-transcriptional pathway, which is relevant to neuron development, mitochondrial function and muscle physiology in health and disease.
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Affiliation(s)
- Ana Julia Fernández-Alvarez
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Malena Lucía Pascual
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Graciela Lidia Boccaccio
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - María Gabriela Thomas
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
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19
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Krishnan P, Ghosh S, Wang B, Li D, Narasimhan A, Berendt R, Graham K, Mackey JR, Kovalchuk O, Damaraju S. Next generation sequencing profiling identifies miR-574-3p and miR-660-5p as potential novel prognostic markers for breast cancer. BMC Genomics 2015; 16:735. [PMID: 26416693 PMCID: PMC4587870 DOI: 10.1186/s12864-015-1899-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/07/2015] [Indexed: 12/14/2022] Open
Abstract
Background Prognostication of Breast Cancer (BC) relies largely on traditional clinical factors and biomarkers such as hormone or growth factor receptors. Due to their suboptimal specificities, it is challenging to accurately identify the subset of patients who are likely to undergo recurrence and there remains a major need for markers of higher utility to guide therapeutic decisions. MicroRNAs (miRNAs) are small non-coding RNAs that function as post-transcriptional regulators of gene expression and have shown promise as potential prognostic markers in several cancer types including BC. Results In our study, we sequenced miRNAs from 104 BC samples and 11 apparently healthy normal (reduction mammoplasty) breast tissues. We used Case–control (CC) and Case-only (CO) statistical paradigm to identify prognostic markers. Cox-proportional hazards regression model was employed and risk score analysis was performed to identify miRNA signature independent of potential confounders. Representative miRNAs were validated using qRT-PCR. Gene targets for prognostic miRNAs were identified using in silico predictions and in-house BC transcriptome dataset. Gene ontology terms were identified using DAVID bioinformatics v6.7. A total of 1,423 miRNAs were captured. In the CC approach, 126 miRNAs were retained with predetermined criteria for good read counts, from which 80 miRNAs were differentially expressed. Of these, four and two miRNAs were significant for Overall Survival (OS) and Recurrence Free Survival (RFS), respectively. In the CO approach, from 147 miRNAs retained after filtering, 11 and 4 miRNAs were significant for OS and RFS, respectively. In both the approaches, the risk scores were significant after adjusting for potential confounders. The miRNAs associated with OS identified in our cohort were validated using an external dataset from The Cancer Genome Atlas (TCGA) project. Targets for the identified miRNAs were enriched for cell proliferation, invasion and migration. Conclusions The study identified twelve non-redundant miRNAs associated with OS and/or RFS. These signatures include those that were reported by others in BC or other cancers. Importantly we report for the first time two new candidate miRNAs (miR-574-3p and miR-660-5p) as promising prognostic markers. Independent validation of signatures (for OS) using an external dataset from TCGA further strengthened the study findings. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1899-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Preethi Krishnan
- Department of Laboratory Medicine and Pathology, University of Alberta, 11560-University Avenue, Edmonton, AB, T6G 1Z2, Canada.
| | - Sunita Ghosh
- Department of Oncology, University of Alberta, Edmonton, AB, Canada. .,Cross Cancer Institute, Edmonton, AB, Canada.
| | - Bo Wang
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, Canada.
| | - Dongping Li
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, Canada.
| | - Ashok Narasimhan
- Department of Laboratory Medicine and Pathology, University of Alberta, 11560-University Avenue, Edmonton, AB, T6G 1Z2, Canada.
| | - Richard Berendt
- Department of Oncology, University of Alberta, Edmonton, AB, Canada. .,Cross Cancer Institute, Edmonton, AB, Canada.
| | - Kathryn Graham
- Department of Oncology, University of Alberta, Edmonton, AB, Canada.
| | - John R Mackey
- Department of Oncology, University of Alberta, Edmonton, AB, Canada. .,Cross Cancer Institute, Edmonton, AB, Canada.
| | - Olga Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, Canada.
| | - Sambasivarao Damaraju
- Department of Laboratory Medicine and Pathology, University of Alberta, 11560-University Avenue, Edmonton, AB, T6G 1Z2, Canada. .,Cross Cancer Institute, Edmonton, AB, Canada.
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20
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Plantié E, Migocka-Patrzałek M, Daczewska M, Jagla K. Model organisms in the fight against muscular dystrophy: lessons from drosophila and Zebrafish. Molecules 2015; 20:6237-53. [PMID: 25859781 PMCID: PMC6272363 DOI: 10.3390/molecules20046237] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 03/31/2015] [Accepted: 04/01/2015] [Indexed: 01/01/2023] Open
Abstract
Muscular dystrophies (MD) are a heterogeneous group of genetic disorders that cause muscle weakness, abnormal contractions and muscle wasting, often leading to premature death. More than 30 types of MD have been described so far; those most thoroughly studied are Duchenne muscular dystrophy (DMD), myotonic dystrophy type 1 (DM1) and congenital MDs. Structurally, physiologically and biochemically, MDs affect different types of muscles and cause individual symptoms such that genetic and molecular pathways underlying their pathogenesis thus remain poorly understood. To improve our knowledge of how MD-caused muscle defects arise and to find efficacious therapeutic treatments, different animal models have been generated and applied. Among these, simple non-mammalian Drosophila and zebrafish models have proved most useful. This review discusses how zebrafish and Drosophila MD have helped to identify genetic determinants of MDs and design innovative therapeutic strategies with a special focus on DMD, DM1 and congenital MDs.
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Affiliation(s)
- Emilie Plantié
- GReD (Genetics, Reproduction and Development laboratory), INSERM U1103, CNRS UMR6293, University of Clermont-Ferrand, 28 place Henri-Dunant, 63000 Clermont-Ferrand, France; E-Mail:
| | - Marta Migocka-Patrzałek
- Department of Animal Developmental Biology, Institute of Experimental Biology, University of Wroclaw, 21 Sienkiewicza Street, 50-335 Wroclaw, Poland; E-Mails: (M.M.-P.); (M.D.)
| | - Małgorzata Daczewska
- Department of Animal Developmental Biology, Institute of Experimental Biology, University of Wroclaw, 21 Sienkiewicza Street, 50-335 Wroclaw, Poland; E-Mails: (M.M.-P.); (M.D.)
| | - Krzysztof Jagla
- GReD (Genetics, Reproduction and Development laboratory), INSERM U1103, CNRS UMR6293, University of Clermont-Ferrand, 28 place Henri-Dunant, 63000 Clermont-Ferrand, France; E-Mail:
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21
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Chartier A, Klein P, Pierson S, Barbezier N, Gidaro T, Casas F, Carberry S, Dowling P, Maynadier L, Bellec M, Oloko M, Jardel C, Moritz B, Dickson G, Mouly V, Ohlendieck K, Butler-Browne G, Trollet C, Simonelig M. Mitochondrial dysfunction reveals the role of mRNA poly(A) tail regulation in oculopharyngeal muscular dystrophy pathogenesis. PLoS Genet 2015; 11:e1005092. [PMID: 25816335 PMCID: PMC4376527 DOI: 10.1371/journal.pgen.1005092] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 02/23/2015] [Indexed: 01/25/2023] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD), a late-onset disorder characterized by progressive degeneration of specific muscles, results from the extension of a polyalanine tract in poly(A) binding protein nuclear 1 (PABPN1). While the roles of PABPN1 in nuclear polyadenylation and regulation of alternative poly(A) site choice are established, the molecular mechanisms behind OPMD remain undetermined. Here, we show, using Drosophila and mouse models, that OPMD pathogenesis depends on affected poly(A) tail lengths of specific mRNAs. We identify a set of mRNAs encoding mitochondrial proteins that are down-regulated starting at the earliest stages of OPMD progression. The down-regulation of these mRNAs correlates with their shortened poly(A) tails and partial rescue of their levels when deadenylation is genetically reduced improves muscle function. Genetic analysis of candidate genes encoding RNA binding proteins using the Drosophila OPMD model uncovers a potential role of a number of them. We focus on the deadenylation regulator Smaug and show that it is expressed in adult muscles and specifically binds to the down-regulated mRNAs. In addition, the first step of the cleavage and polyadenylation reaction, mRNA cleavage, is affected in muscles expressing alanine-expanded PABPN1. We propose that impaired cleavage during nuclear cleavage/polyadenylation is an early defect in OPMD. This defect followed by active deadenylation of specific mRNAs, involving Smaug and the CCR4-NOT deadenylation complex, leads to their destabilization and mitochondrial dysfunction. These results broaden our understanding of the role of mRNA regulation in pathologies and might help to understand the molecular mechanisms underlying neurodegenerative disorders that involve mitochondrial dysfunction. Oculopharyngeal muscular dystrophy is a genetic disease characterized by progressive degeneration of specific muscles, leading to ptosis (eyelid drooping), dysphagia (swallowing difficulties) and proximal limb weakness. The disease results from mutations in a nuclear protein called poly(A) binding protein nuclear 1 that is involved in polyadenylation of messenger RNAs (mRNAs) and poly(A) site selection. To address the molecular mechanisms involved in the disease, we have used two animal models (Drosophila and mouse) that recapitulate the features of this disorder. We show that oculopharyngeal muscular dystrophy pathogenesis depends on defects in poly(A) tail length regulation of specific mRNAs. Because poly(A) tails play an essential role in mRNA stability, these defects result in accelerated decay of these mRNAs. The affected mRNAs encode mitochondrial proteins, and mitochondrial activity is impaired in diseased muscles. These findings have important implications for the development of potential therapies for oculopharyngeal muscular dystrophy, and might be relevant to decipher the molecular mechanisms underlying other disorders that involve mitochondrial dysfunction.
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Affiliation(s)
- Aymeric Chartier
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
| | - Pierre Klein
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - Stéphanie Pierson
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
| | - Nicolas Barbezier
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
| | - Teresa Gidaro
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - François Casas
- INRA, UMR 866 Différenciation cellulaire et croissance, Montpellier, France
| | - Steven Carberry
- Department of Biology, National University of Ireland, Maynooth, Ireland
| | - Paul Dowling
- Department of Biology, National University of Ireland, Maynooth, Ireland
| | - Laurie Maynadier
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
| | - Maëlle Bellec
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
| | - Martine Oloko
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - Claude Jardel
- Service de Biochimie Métabolique et Centre de Génétique moléculaire et chromosomique, INSERM U1016, Institut Cochin, CNRS UMR 8104, AP-HP, GHU Pitié-Salpêtrière, Paris, France
| | - Bodo Moritz
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - George Dickson
- School of Biological Sciences, Royal Holloway - University of London, Egham, Surrey, United Kingdom
| | - Vincent Mouly
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - Kay Ohlendieck
- Department of Biology, National University of Ireland, Maynooth, Ireland
| | - Gillian Butler-Browne
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - Capucine Trollet
- Sorbonne Universités, UPMC Univ Paris 06, UM76, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, Paris, France
| | - Martine Simonelig
- mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR1142, Montpellier, France
- * E-mail:
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22
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Mutation of mouse Samd4 causes leanness, myopathy, uncoupled mitochondrial respiration, and dysregulated mTORC1 signaling. Proc Natl Acad Sci U S A 2014; 111:7367-72. [PMID: 24799716 DOI: 10.1073/pnas.1406511111] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Sterile alpha motif domain containing protein 4 (Samd4) is an RNA binding protein that mediates translational repression. We identified a Samd4 missense mutation, designated supermodel, that caused leanness and kyphosis associated with myopathy and adipocyte defects in C57BL/6J mice. The supermodel mutation protected homozygous mice from high fat diet-induced obesity, likely by promoting enhanced energy expenditure through uncoupled mitochondrial respiration. Glucose tolerance was impaired due to diminished insulin release in homozygous mutant mice. The defects of metabolism in supermodel mice may be explained by dysregulated mechanistic target of rapamycin complex 1 (mTORC1) signaling, evidenced by hypophosphorylation of 4E-BP1 and S6 in muscle and adipose tissues of homozygous mice. Samd4 may interface with mTORC1 signaling through an interaction with 14-3-3 proteins and with Akt, which phosphorylates Samd4 in vitro.
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