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Xiao Y, Xie S, Li HD, Liu Y, Zhang H, Zuo X, Zhu H, Li Y, Luo H. Characterised intron retention profiles in muscle tissue of idiopathic inflammatory myopathy subtypes. Ann Rheum Dis 2024; 83:901-914. [PMID: 38302260 DOI: 10.1136/ard-2023-225035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 01/23/2024] [Indexed: 02/03/2024]
Abstract
OBJECTIVES Idiopathic inflammatory myopathies (IIMs) are a group of heterogeneous autoimmune diseases. Intron retention (IR) serves as an important post-transcriptional and translational regulatory mechanism. This study aims to identify changes in IR profiles in IIM subtypes, investigating their influence on proteins and their correlations with clinical features. METHODS RNA sequencing and liquid chromatography-tandem mass spectrometry were performed on muscle tissues obtained from 174 patients with IIM and 19 controls, following QC procedures. GTFtools and iREAD software were used for IR identification. An analysis of differentially expressed IRs (DEIs), exons and proteins was carried out using edgeR or DEP. Functional analysis was performed with clusterProfiler, and SPIRON was used to assess splicing factors. RESULTS A total of 6783 IRs located in 3111 unique genes were identified in all IIM subtypes compared with controls. IIM subtype-specific DEIs were associated with the pathogenesis of respective IIM subtypes. Splicing factors YBX1 and HSPA2 exhibited the most changes in dermatomyositis and immune-mediated necrotising myopathy. Increased IR was associated with reduced protein expression. Some of the IIM-specific DEIs were correlated with clinical parameters (skin rash, MMT-8 scores and muscle enzymes) and muscle histopathological features (myofiber necrosis, regeneration and inflammation). IRs in IFIH1 and TRIM21 were strongly correlated with anti-MDA5+ antibody, while IRs in SRP14 were associated with anti-SRP+ antibody. CONCLUSION This study revealed distinct IRs and specific splicing factors associated with IIM subtypes, which might be contributing to the pathogenesis of IIM. We also emphasised the potential impact of IR on protein expression in IIM muscles.
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Affiliation(s)
- Yizhi Xiao
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
| | - Shasha Xie
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
| | - Hong-Dong Li
- School of Computer Science and Engineering, Central South University, Changsha, Hunan, China PR
| | - Yanjuan Liu
- Institute of Emergency Medicine, Hunan Provincial People's Hospital/The First Affiliated Hospital of Hunan Normal University, Changsha, Hunan, China PR
| | - Huali Zhang
- Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha, Hunan, China PR
| | - Xiaoxia Zuo
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
| | - Honglin Zhu
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
| | - Yisha Li
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
| | - Hui Luo
- Department of Rheumatology and Immunology, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- Provincial Clinical Research Center for Rheumatic and Immunologic Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China PR
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García-Cruz C, Aragón J, Lourdel S, Annan A, Roger JE, Montanez C, Vaillend C. Tissue- and cell-specific whole-transcriptome meta-analysis from brain and retina reveals differential expression of dystrophin complexes and new dystrophin spliced isoforms. Hum Mol Genet 2022; 32:659-676. [PMID: 36130212 PMCID: PMC9896479 DOI: 10.1093/hmg/ddac236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 02/07/2023] Open
Abstract
The large DMD gene encodes a group of dystrophin proteins in brain and retina, produced from multiple promoters and alternative splicing events. Dystrophins are core components of different scaffolding complexes in distinct cell types. Their absence may thus alter several cellular pathways, which might explain the heterogeneous genotype-phenotype relationships underlying central comorbidities in Duchenne muscular dystrophy (DMD). However, the cell-specific expression of dystrophins and associated proteins (DAPs) is still largely unknown. The present study provides a first RNA-Seq-based reference showing tissue- and cell-specific differential expression of dystrophins, splice variants and DAPs in mouse brain and retina. We report that a cell type may express several dystrophin complexes, perhaps due to expression in separate cell subdomains and/or subpopulations, some of which with differential expression at different maturation stages. We also identified new splicing events in addition to the common exon-skipping events. These include a new exon within intron 51 (E51b) in frame with the flanking exons in retina, as well as inclusions of intronic sequences with stop codons leading to the presence of transcripts with elongated exons 40 and/or 41 (E40e, E41e) in both retina and brain. PCR validations revealed that the new exons may affect several dystrophins. Moreover, immunoblot experiments using a combination of specific antibodies and dystrophin-deficient mice unveiled that the transcripts with stop codons are translated into truncated proteins lacking their C-terminus, which we called N-Dp427 and N-Dp260. This study thus uncovers a range of new findings underlying the complex neurobiology of DMD.
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Affiliation(s)
| | | | - Sophie Lourdel
- Institut des Neurosciences Paris Saclay, Université Paris-Saclay, CNRS, 91400 Saclay, France
| | - Ahrmad Annan
- Institut des Neurosciences Paris Saclay, Université Paris-Saclay, CNRS, 91400 Saclay, France
| | - Jérôme E Roger
- To whom correspondence should be addressed. E-mail: (C.V.); (C.M.); (J.E.R.)
| | - Cecilia Montanez
- To whom correspondence should be addressed. E-mail: (C.V.); (C.M.); (J.E.R.)
| | - Cyrille Vaillend
- To whom correspondence should be addressed. E-mail: (C.V.); (C.M.); (J.E.R.)
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3
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Niba ETE, Awano H, Lee T, Takeshima Y, Shinohara M, Nishio H, Matsuo M. Dystrophin Dp71 Subisoforms Localize to the Mitochondria of Human Cells. Life (Basel) 2021; 11:life11090978. [PMID: 34575126 PMCID: PMC8468555 DOI: 10.3390/life11090978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 11/26/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by deficiency in dystrophin, a protein product encoded by the DMD gene. Mitochondrial dysfunction is now attracting much attention as a central player in DMD pathology. However, dystrophin has never been explored in human mitochondria. Here, we analyzed dystrophin in cDNAs and mitochondrial fractions of human cells. Mitochondrial fraction was obtained using a magnetic-associated cell sorting (MACS) technology. Dystrophin was analyzed by reverse transcription (RT)-PCR and western blotting using an antibody against the dystrophin C-terminal. In isolated mitochondrial fraction from HEK293 cells, dystrophin was revealed as a band corresponding to Dp71b and Dp71ab subisoforms. Additionally, in mitochondria from HeLa, SH-SY5Y, CCL-136 and HepG2 cells, signals for Dp71b and Dp71ab were revealed as well. Concomitantly, dystrophin mRNAs encoding Dp71b and Dp71ab were disclosed by RT-PCR in these cells. Primary cultured myocytes from three dystrophinopathy patients showed various levels of mitochondrial Dp71 expression. Coherently, levels of mRNA were different in all cells reflecting the protein content, which indicated predominant accumulation of Dp71. Dystrophin was demonstrated to be localized to human mitochondrial fraction, specifically as Dp71 subisoforms. Myocytes derived from dystrophinopathy patients manifested different levels of mitochondrial Dp71, with higher expression revealed in myocytes from Becker muscular dystrophy (BMD) patient-derived myocytes.
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Affiliation(s)
- Emma Tabe Eko Niba
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan;
- Correspondence: ; Tel.: +81-78-382-5543
| | - Hiroyuki Awano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan;
| | - Tomoko Lee
- Department of Pediatrics, Hyogo College of Medicine, Nishinomiya 663-8501, Japan; (T.L.); (Y.T.)
| | - Yasuhiro Takeshima
- Department of Pediatrics, Hyogo College of Medicine, Nishinomiya 663-8501, Japan; (T.L.); (Y.T.)
| | - Masakazu Shinohara
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan;
| | - Hisahide Nishio
- Department of Occupational Therapy, Faculty of Rehabilitation, Kobe Gakuin University, Kobe 651-2180, Japan;
| | - Masafumi Matsuo
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, Kobe 651-2180, Japan;
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Teramoto N, Sugihara H, Yamanouchi K, Nakamura K, Kimura K, Okano T, Shiga T, Shirakawa T, Matsuo M, Nagata T, Daimon M, Matsuwaki T, Nishihara M. Pathological evaluation of rats carrying in-frame mutations in the dystrophin gene: a new model of Becker muscular dystrophy. Dis Model Mech 2020; 13:dmm044701. [PMID: 32859695 PMCID: PMC7541341 DOI: 10.1242/dmm.044701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 08/18/2020] [Indexed: 01/10/2023] Open
Abstract
Dystrophin, encoded by the DMD gene on the X chromosome, stabilizes the sarcolemma by linking the actin cytoskeleton with the dystrophin-glycoprotein complex (DGC). In-frame mutations in DMD cause a milder form of X-linked muscular dystrophy, called Becker muscular dystrophy (BMD), characterized by the reduced expression of truncated dystrophin. So far, no animal model with in-frame mutations in Dmd has been established. As a result, the effect of in-frame mutations on the dystrophin expression profile and disease progression of BMD remains unclear. In this study, we established a novel rat model carrying in-frame Dmd gene mutations (IF rats) and evaluated the pathology. We found that IF rats exhibited reduced expression of truncated dystrophin in a proteasome-independent manner. This abnormal dystrophin expression caused dystrophic changes in muscle tissues but did not lead to functional deficiency. We also found that the expression of additional dystrophin named dpX, which forms the DGC in the sarcolemma, was associated with the appearance of truncated dystrophin. In conclusion, the outcomes of this study contribute to the further understanding of BMD pathology and help elucidate the efficiency of dystrophin recovery treatments in Duchenne muscular dystrophy, a more severe form of X-linked muscular dystrophy.
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Affiliation(s)
- Naomi Teramoto
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Hidetoshi Sugihara
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Keitaro Yamanouchi
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Katsuyuki Nakamura
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Koichi Kimura
- Department of General Medicine, The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, 108-8639, Japan
- Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Tomoko Okano
- Department of Laboratory Medicine, The University of Tokyo Hospital, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Takanori Shiga
- Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Taku Shirakawa
- Research Center for Locomotion Biology, Kobe Gakuin University, Nishi, Kobe, 651-2180, Japan
- KNC Department of Nucleic Acid Drug Discovery, Faculty of Rehabilitation, Kobe Gakuin University, Nishi, Kobe, 651-2180, Japan
| | - Masafumi Matsuo
- Research Center for Locomotion Biology, Kobe Gakuin University, Nishi, Kobe, 651-2180, Japan
- KNC Department of Nucleic Acid Drug Discovery, Faculty of Rehabilitation, Kobe Gakuin University, Nishi, Kobe, 651-2180, Japan
| | - Tetsuya Nagata
- Department of Neurology and Neurological Science, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Masao Daimon
- Department of Laboratory Medicine, The University of Tokyo Hospital, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Takashi Matsuwaki
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Masugi Nishihara
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan
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Yamamoto T, Miura A, Itoh K, Takeshima Y, Nishio H. RNA sequencing reveals abnormal LDB3 splicing in sudden cardiac death. Forensic Sci Int 2019; 302:109906. [DOI: 10.1016/j.forsciint.2019.109906] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 07/21/2019] [Indexed: 02/07/2023]
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Detection of Dystrophin Dp71 in Human Skeletal Muscle Using an Automated Capillary Western Assay System. Int J Mol Sci 2018; 19:ijms19061546. [PMID: 29789502 PMCID: PMC6032138 DOI: 10.3390/ijms19061546] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 12/26/2022] Open
Abstract
Background: Dystrophin Dp71 is one of the isoforms produced by the DMD gene which is mutated in patients with Duchenne muscular dystrophy (DMD). Although Dp71 is expressed ubiquitously, it has not been detected in normal skeletal muscle. This study was performed to assess the expression of Dp71 in human skeletal muscle. Methods: Human skeletal muscle RNA and tissues were obtained commercially. Mouse skeletal muscle was obtained from normal and DMDmdx mice. Dp71 mRNA and protein were determined by reverse-transcription PCR and an automated capillary Western assay system, the Simple Western, respectively. Dp71 was over-expressed or suppressed using a plasmid expressing Dp71 or antisense oligonucleotide, respectively. Results: Full-length Dp71 cDNA was PCR amplified as a single product from human skeletal muscle RNA. A ca. 70 kDa protein peak detected by the Simple Western was determined as Dp71 by over-expressing Dp71 in HEK293 cells, or suppressing Dp71 expression with antisense oligonucleotide in rhabdomyosarcoma cells. The Simple Western assay detected Dp71 in the skeletal muscles of both normal and DMD mice. In human skeletal muscle, Dp71 was also detected. The ratio of Dp71 to vinculin of human skeletal muscle samples varied widely, indicating various levels of Dp71 expression. Conclusions: Dp71 protein was detected in human skeletal muscle using a highly sensitive capillary Western blotting system.
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Normal and altered pre-mRNA processing in the DMD gene. Hum Genet 2017; 136:1155-1172. [DOI: 10.1007/s00439-017-1820-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 06/02/2017] [Indexed: 12/11/2022]
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Niba ETE, Yamanaka R, Rani AQM, Awano H, Matsumoto M, Nishio H, Matsuo M. DMD transcripts in CRL-2061 rhabdomyosarcoma cells show high levels of intron retention by intron-specific PCR amplification. Cancer Cell Int 2017; 17:58. [PMID: 28546788 PMCID: PMC5442858 DOI: 10.1186/s12935-017-0428-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 05/16/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The DMD gene encoding dystrophin is mutated in Duchenne muscular dystrophy, a fatal progressive muscle wasting disease. DMD has also been shown to act as a tumor suppressor gene. Rhabdomyosarcoma (RMS) is a mesodermal sarcoma that shares characteristics of skeletal muscle precursors. Products of the DMD gene in RMS have not yet been fully clarified. Here, DMD products were analyzed in CRL-2061 cells established from alveolar RMS. METHODS The 14-kb long DMD cDNA was PCR amplified as 20 separated fragments, as were nine short intron regions. Dystrophin was analyzed by Western blotting using an antibody against the C-terminal region of dystrophin. RESULTS Sixteen of the 20 DMD cDNA fragments could be amplified from CRL-2061 cells as muscle cDNA. Three fragments included aberrant gene products, including one in which exon 71 was omitted and one each with retention of introns 40 and 58. In one fragment, extending from exon 70 to 79, no normally spliced product was obtained. Rather, six alternatively spliced products were identified, including a new product deleting exon 73, with the most abundant product showing deletion of exon 78. Although dystrophin expression was expected in CRL-2061 cells, western blotting of cell lysates showed no evidence of dystrophin, suggesting that translation of full-length DMD mRNA was inhibited by intron retention that generated a premature stop codon. Intron specific PCR amplification of nine short introns, showed retention of introns 40, 58, and 70, which constituted about 60, 25 and 9%, respectively, of the total PCR amplified products. The most abundant DMD transcript contained two abnormalities, intron 40 retention and exon 78 skipping. CONCLUSIONS Intron-specific PCR amplification showed that DMD transcripts contained high levels of introns 40, 58 and 70. Retention of these introns may have been responsible for the lack of dystrophin expression by CRL-2061 cells, thereby abolishing the tumor suppressor activity of dystrophin.
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Affiliation(s)
- Emma Tabe Eko Niba
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 6512180 Japan
| | - Ryo Yamanaka
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 6512180 Japan
| | - Abdul Qawee Mahyoob Rani
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 6512180 Japan.,Department of Pediatrics, Kobe University Graduate School of Medicine, Chuo, Kobe, 6500017 Japan
| | - Hiroyuki Awano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Chuo, Kobe, 6500017 Japan
| | - Masaaki Matsumoto
- Department of Pediatrics, Kobe University Graduate School of Medicine, Chuo, Kobe, 6500017 Japan
| | - Hisahide Nishio
- Department of Community Medicine and Social Healthcare Sciences, Kobe University Graduate School of Medicine, Chuo, Kobe, 6500017 Japan
| | - Masafumi Matsuo
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 6512180 Japan
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Nishida A, Minegishi M, Takeuchi A, Awano H, Niba ETE, Matsuo M. Neuronal SH-SY5Y cells use the C-dystrophin promoter coupled with exon 78 skipping and display multiple patterns of alternative splicing including two intronic insertion events. Hum Genet 2015; 134:993-1001. [PMID: 26152642 DOI: 10.1007/s00439-015-1581-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 06/27/2015] [Indexed: 01/01/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disease caused by mutations in the dystrophin gene. One-third of DMD cases are complicated by mental retardation. Here, we used reverse transcription PCR to analyze the pattern of dystrophin transcripts in neuronal SH-SY5Y cells. Among the three alternative promoters/first exons at the 5'-end, only transcripts containing the brain cortex-specific C1 exon could be amplified. The C-transcript appeared as two products: a major product of the expected size and a minor larger product that contained the cryptic exon 1a between exons C1 and 2. At the 3'-end there was complete exon 78 skipping. Together, these findings indicate that SH-SY5Y cells have neuron-specific characteristics with regard to both promoter activation and alternative splicing. We also revealed partial skipping of exons 9 and 71. Four amplified products were obtained from a fragment covering exons 36-41: a strong expected product, two weak products lacking either exon 37 or exon 38, and a second strong larger product with a 568-bp insertion between exons 40 and 41. The inserted sequence matched the 3'-end of intron 40 perfectly. We concluded that a cryptic splice site was activated in SH-SY5Y cells to create the novel, unusually large, exon 41e (751 bp). In total, we identified seven alternative splicing events in neuronal SH-SY5Y cells, and calculated that 32 dystrophin transcripts could be produced. Our results may provide clues in the analysis of transcriptype-phenotype correlations as regards mental retardation in DMD.
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Affiliation(s)
- Atsushi Nishida
- Department of Medical Rehabilitation, Faculty of Rehabilitation, Kobegakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 651-2180, Japan
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