{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:50:02Z","timestamp":1760151002104,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,24]],"date-time":"2022-01-24T00:00:00Z","timestamp":1642982400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education, Culture, Sports, Science and Technology, Japan","award":["20K08197"],"award-info":[{"award-number":["20K08197"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disease characterized by defects of lower motor neurons. Approximately 95% of SMA patients are homozygous for survival motor neuron 1 (SMN1) gene deletion, while ~5% carry an intragenic SMN1 mutation. Here, we investigated the stability and oligomerization ability of mutated SMN1 proteins. Plasmids containing wild- and mutant-type SMN1 cDNA were constructed and transfected into HeLa cells. Reverse transcription-polymerase chain reaction (RT-PCR) demonstrated similar abundances of transcripts from the plasmids containing SMN cDNA, but Western blotting showed different expression levels of mutated SMN1 proteins, reflecting the degree of their instability. A mutated SMN1 protein with T274YfsX32 exhibited a much lower expression level than other mutated SMN1 proteins with E134K, Y276H, or Y277C. In immunoprecipitation analysis, the mutated SMN1 protein with T274YfsX32 did not bind to endogenous SMN1 protein in HeLa cells, suggesting that this mutation completely blocks the oligomerization with full-length SMN2 protein in the patient. The patient with T274YfsX32 showed a much more severe phenotype than the other patients with different mutations. In conclusion, the stability and oligomerization ability of mutated SMN1 protein may determine the protein stability and may be associated with the clinical severity of SMA caused by intragenic SMN1 mutation.<\/jats:p>","DOI":"10.3390\/genes13020205","type":"journal-article","created":{"date-parts":[[2022,1,25]],"date-time":"2022-01-25T20:38:58Z","timestamp":1643143138000},"page":"205","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Stability and Oligomerization of Mutated SMN Protein Determine Clinical Severity of Spinal Muscular Atrophy"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1311-3448","authenticated-orcid":false,"given":"Emma","family":"Niba","sequence":"first","affiliation":[{"name":"Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6778-4511","authenticated-orcid":false,"given":"Hisahide","family":"Nishio","sequence":"additional","affiliation":[{"name":"Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan"},{"name":"Department of Occupational Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe 651-2180, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8066-9211","authenticated-orcid":false,"given":"Yogik","family":"Wijaya","sequence":"additional","affiliation":[{"name":"Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mawaddah","family":"Ar Rochmah","sequence":"additional","affiliation":[{"name":"Department of Neurology, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Jalan Farmako, Sekip Utara, Yogyakarta 55281, Indonesia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9993-4433","authenticated-orcid":false,"given":"Toru","family":"Takarada","sequence":"additional","affiliation":[{"name":"Laboratory of Functional Molecular Chemistry, Kobe Pharmaceutical University, 4-19-1 Motoyamakitamachi, Higashinada-ku, Kobe 658-8558, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7841-2783","authenticated-orcid":false,"given":"Atsuko","family":"Takeuchi","sequence":"additional","affiliation":[{"name":"Instrumental Analysis Center, Kobe Pharmaceutical University, 4-19-1 Motoyamakitamachi, Higashinada-ku, Kobe 658-8558, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2809-4670","authenticated-orcid":false,"given":"Tomokazu","family":"Kimizu","sequence":"additional","affiliation":[{"name":"Department of Pediatric Neurology, Osaka Women\u2019s and Children\u2019s Hospital, 840 Murodo-cho, Izumi 594-1101, Osaka, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5677-4222","authenticated-orcid":false,"given":"Kentaro","family":"Okamoto","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Ehime Prefectural Imabari Hospital, 4-5-5 Ishii-cho, Imabari 794-0006, Ehime, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Toshio","family":"Saito","sequence":"additional","affiliation":[{"name":"Department of Neurology, National Hospital Organization Osaka Toneyama Medical Center, 5-1-1 Toneyama, Toyonaka 560-8552, Osaka, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9846-4142","authenticated-orcid":false,"given":"Hiroyuki","family":"Awano","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6468-7185","authenticated-orcid":false,"given":"Yasuhiro","family":"Takeshima","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masakazu","family":"Shinohara","sequence":"additional","affiliation":[{"name":"Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Hyogo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/j.nmd.2017.11.005","article-title":"Diagnosis and Management of Spinal Muscular Atrophy: Part 1: Recommendations for Diagnosis, Rehabilitation, Orthopedic and Nutritional Care","volume":"28","author":"Mercuri","year":"2018","journal-title":"Neuromuscul. Disord."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1111\/ahg.12031","article-title":"Spinal Muscular Atrophy: From Gene Discovery to Clinical Trials: SMA Gene Discovery to Clinical Trials","volume":"77","author":"Nurputra","year":"2013","journal-title":"Ann. Hum. Genet."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1186\/s13023-017-0671-8","article-title":"Prevalence, Incidence and Carrier Frequency of 5q\u2013Linked Spinal Muscular Atrophy\u2014A Literature Review","volume":"12","author":"Verhaart","year":"2017","journal-title":"Orphanet. J. Rare Dis."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"7S9","DOI":"10.1016\/S0929-693X(20)30270-0","article-title":"Molecular Diagnosis and Genetic Counseling for Spinal Muscular Atrophy (SMA)","volume":"27","author":"Rouzier","year":"2020","journal-title":"Arch. P\u00e9diatr."},{"doi-asserted-by":"crossref","unstructured":"Kimizu, T., Ida, S., Okamoto, K., Awano, H., Niba, E.T.E., Wijaya, Y.O.S., Okazaki, S., Shimomura, H., Lee, T., and Tominaga, K. (2021). Spinal Muscular Atrophy: Diagnosis, Incidence, and Newborn Screening in Japan. IJNS, 7.","key":"ref_5","DOI":"10.3390\/ijns7030045"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1002\/mus.24497","article-title":"Spinal Muscular Atrophy: Diagnosis and Management in a New Therapeutic Era: Spinal Muscular Atrophy","volume":"51","author":"Arnold","year":"2015","journal-title":"Muscle Nerve"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"767","DOI":"10.1038\/344767a0","article-title":"Gene for Chronic Proximal Spinal Muscular Atrophies Maps to Chromosome 5q","volume":"344","author":"Melki","year":"1990","journal-title":"Nature"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/0092-8674(95)90460-3","article-title":"Identification and Characterization of a Spinal Muscular Atrophy-Determining Gene","volume":"80","author":"Lefebvre","year":"1995","journal-title":"Cell"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"6307","DOI":"10.1073\/pnas.96.11.6307","article-title":"A Single Nucleotide in the SMN Gene Regulates Splicing and Is Responsible for Spinal Muscular Atrophy","volume":"96","author":"Lorson","year":"1999","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1093\/hmg\/9.2.259","article-title":"An Exonic Enhancer Is Required for Inclusion of an Essential Exon in the SMA-Determining Gene SMN","volume":"9","author":"Lorson","year":"2000","journal-title":"Hum. Mol. Genet."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1107","DOI":"10.1128\/MCB.01262-08","article-title":"Regulation of SMN Protein Stability","volume":"29","author":"Burnett","year":"2009","journal-title":"Mol. 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Mutat."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1016\/j.braindev.2021.03.006","article-title":"Phenotypes of SMA Patients Retaining SMN1 with Intragenic Mutation","volume":"43","author":"Wijaya","year":"2021","journal-title":"Brain Dev."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1002\/mgg3.10","article-title":"A Homozygous Double Mutation in SMN 1: A Complicated Genetic Diagnosis of SMA","volume":"1","author":"Kirwin","year":"2013","journal-title":"Mol. Genet. Genom. Med."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1002\/humu.10245","article-title":"A Genetic and Phenotypic Analysis in Spanish Spinal Muscular Atrophy Patients with c.399_402del AGAG, the Most Frequently Found Subtle Mutation in the SMN1 Gene: Genotype-phenotype analysis in SMN1","volume":"22","author":"Baiget","year":"2003","journal-title":"Hum. Mutat."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1212\/WNL.0b013e318247ca69","article-title":"Genotype-Phenotype Relationship in 2 SMA III Patients with Novel Mutations in the Tudor Domain","volume":"78","author":"Fraidakis","year":"2012","journal-title":"Neurology"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"914","DOI":"10.1016\/j.braindev.2013.11.009","article-title":"Intragenic Mutations in SMN1 May Contribute More Significantly to Clinical Severity than SMN2 Copy Numbers in Some Spinal Muscular Atrophy (SMA) Patients","volume":"36","author":"Yamamoto","year":"2014","journal-title":"Brain Dev."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"624","DOI":"10.1007\/s00415-006-0410-x","article-title":"A Novel Mutation at the N-Terminal of SMN Tudor Domain Inhibits Its Interaction with Target Proteins","volume":"254","author":"Kotani","year":"2007","journal-title":"J. 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Genet."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"11167","DOI":"10.1073\/pnas.96.20.11167","article-title":"SMN Mutants of Spinal Muscular Atrophy Patients Are Defective in Binding to SnRNP Proteins","volume":"96","author":"Pellizzoni","year":"1999","journal-title":"Proc. Nat. Acad. Sci. USA"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"20185","DOI":"10.1074\/jbc.M115.667279","article-title":"Oligomeric Properties of Survival Motor Neuron\u00b7Gemin2 Complexes","volume":"290","author":"Gupta","year":"2015","journal-title":"J. Biol. Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"5543","DOI":"10.1128\/MCB.25.13.5543-5551.2005","article-title":"The Survival of Motor Neurons Protein Determines the Capacity for SnRNP Assembly: Biochemical Deficiency in Spinal Muscular Atrophy","volume":"25","author":"Wan","year":"2005","journal-title":"Mol. 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Nat. Acad. Sci. USA"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3914","DOI":"10.1523\/JNEUROSCI.3631-10.2011","article-title":"The Survival of Motor Neuron (SMN) Protein Interacts with the MRNA-Binding Protein HuD and Regulates Localization of Poly(A) MRNA in Primary Motor Neuron Axons","volume":"31","author":"Fallini","year":"2011","journal-title":"J. Neurosci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1093\/hmg\/ddq500","article-title":"HuD Interacts with Survival Motor Neuron Protein and Can Rescue Spinal Muscular Atrophy-like Neuronal Defects","volume":"20","author":"Hubers","year":"2011","journal-title":"Hum. Mol. Genet."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"11559","DOI":"10.1523\/JNEUROSCI.1528-17.2017","article-title":"HuD and the Survival Motor Neuron Protein Interact in Motoneurons and Are Essential for Motoneuron Development, Function, and MRNA Regulation","volume":"37","author":"Duy","year":"2017","journal-title":"J. Neurosci."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.semcdb.2014.04.026","article-title":"SMN Control of RNP Assembly: From Post-Transcriptional Gene Regulation to Motor Neuron Disease","volume":"32","author":"Li","year":"2014","journal-title":"Semin. Cell Dev. Biol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"3404","DOI":"10.1093\/hmg\/ddy251","article-title":"Mild SMN Missense Alleles Are Only Functional in the Presence of SMN2 in Mammals","volume":"27","author":"Iyer","year":"2018","journal-title":"Hum. Mol. Genet."}],"container-title":["Genes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4425\/13\/2\/205\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:06:21Z","timestamp":1760133981000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4425\/13\/2\/205"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,24]]},"references-count":43,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2022,2]]}},"alternative-id":["genes13020205"],"URL":"https:\/\/doi.org\/10.3390\/genes13020205","relation":{},"ISSN":["2073-4425"],"issn-type":[{"type":"electronic","value":"2073-4425"}],"subject":[],"published":{"date-parts":[[2022,1,24]]}}}