一般口演（Oral）

Oral ALS-1 一般口演 ALS-1

7月25日（木）9:00～9:15　第8会場（朱鷺メッセ　3F　303+304） 1O-08m1-1 Rab1A rescues mutant cyclin F-induced impairment of ER vesicular transport in ALS/FTD Audrey Marie Ragagnin（Ragagnin Audrey Marie），Vinod Sundaramoorthy（Sundaramoorthy Vinod），Sonam Parakh（Parakh Sonam），Emma Perri（Perri Emma），Angela Laird（Laird Angela），Julie Atkin（Atkin Julie） Macquarie University, Sydney, Australia Mutations in the CCNF gene encoding cyclin F are associated with sporadic and familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), but the underlying pathophysiological mechanisms are unknown. Proper functioning of the endoplasmic reticulum (ER) is essential for physiological cellular function. RabGTPases regulate cellular transport and other functions and Rab1A mediates multiple ER-related activities. Here, we demonstrate that cyclin F normally is present within the ER. Furthermore, mutant ALS/FTD-associated cyclin F dysregulates ER-Golgi transport by a mechanism involving aberrant ubiquitination activity of Sec31, leading to smaller ER-derived vesicles budding from the ER, which impedes transport of larger proteins (>100kDa). This perturbs ER-associated degradation, leading to ER stress, Golgi fragmentation and apoptosis. However, these events are prevented by over-expression of Rab1A. Moreover, Rab1A prevents axonopathy in zebrafish expressing ALS/FTD-associated mutant cyclin F. Together, these results demonstrate that ER dysfunction is a pathogenic pathway associated with ALS/FTD-variant cyclin F and that Rab1A-mediated ER-Golgi transport is a novel therapeutic target in ALS/FTD patients bearing CCNF mutations.		7月25日（木）9:15～9:30　第8会場（朱鷺メッセ　3F　303+304） 1O-08m1-2 日本の筋萎縮性側索硬化症におけるATXN8OS 遺伝子の非翻訳領域リピート延長の同定 Makito Hirano（平野牧人）¹，Makoto Samukawa（寒川真）¹，Chiharu Isono（磯野千春）²，Kazumasa Saigoh（西郷和真）¹，Yusaku Nakamura（中村雄作）³，Susumu Kusunoki（楠進）¹ ¹近畿大学神経内科 ²近畿大学リハビリテーション部 ³近畿大学地域医療連携学総合　神経内科部門 Non-coding repeat expansions in the C9ORF72 gene is frequently found in sporadic ALS in Western countries (4~21% of all sporadic ALS), but is rare in Japan (<0.5%). Spinocerebellar ataxia type 8 (SCA8) is a non-coding repeat disease caused by expanded CTA/CTG repeats in the ATXN8OS gene. Many patients had pure cerebellar ataxia, while some had parkinsonism. Several lines of evidence suggest the involvement of upper and lower motor neurons in SCA8, but a positive association between SCA8 and ALS remains unknown. Spinocerebellar ataxia type 36 (SCA36), characterized by motor neuron involvement, is another non-coding repeat disease caused by mutations in the NOP56 gene. We analyzed the ATXN8OS, C9ORF72, and NOP56 genes in 102 Japanese patients with sporadic ALS and in 10 patients with mutations in know ALS-genes. We found that three of the 102 patients with sporadic ALS (3%) had mutations in the ATXN8OS gene, while no patient had a mutation in the C9ORF72 or NOP56 gene. No patient had two different mutated genes. The mutation-positive patients were clinically characterized by neck weakness or bulbar-predominant symptoms. Fibroblasts of two of the three patients were available, and were susceptible to oxidative stress, the result of which was consistent with the reported finding for sporadic patients with unknown causes (Ann Neurol 43;452:1998). Three percent seems small, but is still relatively large for Japan, since the most commonly mutated genes, the SOD1 and SQSTM1 genes, only account for 2-3% of sporadic patients each. Our results for the first time suggest the importance of non-coding repeat expansions in Japanese patients with ALS, and extend the clinical phenotype of SCA8.

7月25日（木）9:30～9:45　第8会場（朱鷺メッセ　3F　303+304） 1O-08m1-3 ALS2疾患原因変異体の高次構造の変化はALS2が担うエンドソーム機能を喪失させる Kai Sato（佐藤海）¹，Asako Otomo（大友麻子）^1,2，Mahoko Takahashi Ueda（高橋ー上田真保子）²，Yui Hiratsuka（平塚結衣）¹，Kyoko Suzuki-Utsunomiya（鈴木―宇都宮恭子）¹，Junya Sugiyama（杉山純也）¹，Shuji Murakoshi（村越秀治）¹，Shun Mitsui（三井駿）¹，Suzuka Ono（小野鈴花）¹，So Nakagawa（中川草）^1,2，Hui-Fang Shang（Shang Hui-Fang）³，Shinji Hadano（秦野伸二）¹ ¹東海大学医学部分子生命科学 ²東海大学マイクロ・ナノ研究開発センター ³四川大学華西医院　神経内科 Loss of function mutations in the ALS2 gene account for a number of juvenile autosomal recessive motor neuron diseases. The ALS2 gene product, ALS2/alsin, forms a homophilic oligomer and acts as a guanine nucleotide exchange factor (GEF) for the small GTPase Rab5. This oligomerization is crucial for both Rab5 GEF activity and ALS2-mediated endosome fusion and maturation in cells. However, the molecular mechanism by which pathogenic missense ALS2 variants retaining the Rab5 GEF activity fail to properly localize to endosomes remains to be clarified. To address this issue, we investigated the relationship between intracellular localization and oligomeric states of pathogenic ALS2 variants. Upon Rac1 activation, all pathogenic ALS2 mutants recruited from the cytosol to membrane ruffles, but not to macropinosomes and/or endosomes. Most wild-type ALS2 complexes were tetramers, while the sizes of an ALS2 complex carrying missense mutations in the N-terminus of RLD or in-frame amino acid deletion in the PH domain were shifted toward higher molecular weight. Further, the C-terminal VPS9 domain missense mutant existed as a smaller dimeric or trimeric smaller form. Mutagenesis analyses in silico in conjunction with a cycloheximide chase assay in vitro disclosed that these missense mutations led to decrease in the protein stability. These results indicate that disorganized higher structures of ALS2 variants can explain their impaired endosomal localization and the stability, leading to loss of the ALS2 function in cells.		7月25日（木）9:45～10:00　第8会場（朱鷺メッセ　3F　303+304） 1O-08m1-4 オリゴデンドログリアにおけるalpha-synuclein過剰発現によるPPMS/MSAモデルマウスの開発 Dai Matsuse（松瀬大）¹，Hiroo Yamaguchi（山口浩雄）¹，Toru Saiga（雑賀徹）¹，Katsuhisa Masaki（真崎勝久）¹，Yiwen Cui（崔訳文）¹，Ryo Yamasaki（山﨑亮）¹，Kenji Tanaka（田中謙二）²，Jun-ichi Kira（吉良潤一）¹ ¹九州大医学研究院神経内科学 ²慶應大医精神・神経科学 Aim: Multiple system atrophy (MSA) is a neurodegenerative disorder, in which alpha -synuclein (a-syn) accumulates in oligodendroglias. However, accumulation of a-syn also can be seen in glia and neurons in multiple sclerosis (MS). Epidemiologically, some MS patients later develop MSA. These facts suggest that there may be a common mechanism between these diseases. Primary progressive MS (PPMS) pathologically shows oligodendroglia dystrophy; however, neither animal models nor curative drugs exist. Therefore, we aimed to establish a novel mice model of PPMS/MSA by overexpression of mutant a-syn in oligodendroglia in a temporarily restrictive manner using Tet-off system. Methods: We generated TetO- a-syn A53T Tg/+; PLP-tTA Tg/+ double transgenic mice, which express mutant human A53T a-syn, which causes familial Parkionson disease because of strong aggregability and cytotoxicity, in oligodendroglia while they are fed without doxycycline. Results: Mice with A53T a-syn expression since myelination period showed progressive monoparesis/hemiparesis/paraparesis and ataxia. A53T a-syn accumulated asymmetrically in the spinal cord, brainstem and cerebellum. Extensive but asymmetric demyelinations were observed with activated microglia and astroglia accompanied by mild infiltration of T cell, B cell, and macrophage. Mice with A53T a-syn expression after myelination period showed bradykinesia and tremor besides limb weakness and ataxia, reminiscent of MSA. These mice had inflammatory demyelination in the brainstem and cerebellum and striatal atrophy. Microarrays revealed marked upregulation of innate and acquired immunity-related gene expressions in the spinal cord. Conclusion: Expression of abnormal proteins such as mutant a-syn in oligodendroglia during myelination period may produce inflammatory demyelination predominantly in the spinal cord simulating PPMS while expression of such proteins in later period may cause inflammatory demyelination predominantly in the brainstem and cerebellum resembling MSA.