一般ポスター

一般ポスター神経変性疾患-1

7月6日（木）　13:20-14:20　ポスター会場① 1P⑤-1 マウスにおけるオリゴデンドロサイト特異的な変異型TDP-43過剰発現は運動機能障害を惹起する Oligodendrocyte-specific overexpression of mutant TDP-43 induces motor dysfunction in mice 堀内　麻衣, 渡邊　征爾, 山中　宏二名古屋大学　環境医学研究所　病態神経科学分野 Mai Horiuchi, Seiji Watanabe, Koji Yamanaka Dept. of Neurosci. & Pathobiol., RIEM, Nagoya Univ. TAR DNA binding protein-43 (TDP-43), encoded by the TARDBP gene, is an evolutionally conserved nucleotide-binding protein that regulates multiple aspects of RNA metabolism. TDP-43 is mostly localized in nucleus, however, cytoplasmic mislocalization and aggregate formation of TDP-43 are recognized as a pathological hallmark of amyotrophic lateral sclerosis (ALS). The pathological changes in TDP-43 are mainly observed in neurons but also present in oligodendrocytes. Mice overexpressing TDP-43 in neurons induce neuronal dysfunction and death, suggesting the gain-of-toxicity mechanism of TDP-43 in ALS. However, the gain-of-toxicity mechanism of TDP-43 in oligodendrocytes has not been unveiled. We established TDP-43 conditional transgenic mice (cTg-TDP-43^M337V), which overexpress human TDP-43 cDNA carrying ALS-causative M337V mutation under the CAG promoter in a Cre-dependent manner, then cTg-TDP-43^M337V mice were crossbred with Mbp-Cre transgenic mice. The mice doubly positive for cTg-TDP-43^M337V and Mbp-Cre showed a Cre-dependent increase of TDP-43 proteins in the neural tissues. Cre-positive cTg-TDP-43^M337V mice exhibited motor dysfunction revealed by a balanced beam test. Besides, we found myelin pallor and glial activation in the white matter of Mbp-Cre(+)/cTg-TDP-43^M337V. We speculate that excess amount of TDP-43 compromises physiological functions of oligodendrocytes.		7月6日（木）　13:20-14:20　ポスター会場① 1P⑤-2 TBK1は単量体化によって誘導されるリン酸化TDP-43のクリアランスに重要である TBK1 is crucial for a clearance of monomerization-induced phosphorylated TDP-43 酒井　昭平¹, 渡邊　征爾¹, 大岩　康太郎^1,2, 山中　宏二¹ 1. 名古屋大学　環境医学研究所　病態神経科学分野、名古屋、日本, 2. 名古屋大学神経内科、名古屋、日本 Shohei Sakai¹, Seiji Watanabe¹, Kotaro Oiwa^1,2, Koji Yamanaka¹ 1. Dept. of Neuroscience and Pathobiology, RIEM, Nagoya University, Nagoya, Japan, 2. Dept. of Neurology, Nagoya University, Nagoya, Japan Abnormal accumulation of phosphorylated TDP-43 in brains and spinal cords, known as TDP-43 pathology, is a common pathological hallmark in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). TBK1 is one of notable genes to study the molecular basis of TDP-43 pathology because it is a common causative gene in ALS and FTLD. However, the molecular link between TBK1 and TDP-43 pathology mostly remains unknown due to the difficulty in reproducing TDP-43 pathology in experimental models. Recently, we discovered that monomeric TDP-43 mutants robustly recapitulate TDP-43 pathology-like features in vitro. Based on the finding, this study aimed to clarify whether TBK1 regulates TDP-43 pathology induced by monomeric TDP-43. First, we discovered that a loss of TBK1 function exacerbated accumulation of phosphorylated TDP-43 in culture cells. Next, we found that overexpression of wild-type TBK1 promoted a drastic reduction in phosphorylated TDP-43, while some ALS/FTLD-linked TBK1 mutants induced partial or no reduction. These results provide direct evidence that TBK1 is a potent repressor against TDP-43 pathology. Recently, we successfully established a new model mouse expressing monomeric TDP-43 for in vivo experiments. In the future, we plan to utilize this model and TBK1 KO mouse to verify the significance of TBK1 against TDP-43 pathology in vivo.

7月6日（木）　13:20-14:20　ポスター会場① 1P⑤-3 TIRFMを用いたiPS細胞由来神経細胞における内在性Tauの動態の解明 Dynamics of endogenous Tau in iPS-derived neurons revealed by TIRFM 大山　千聖¹, 前田　純宏², 岡野　栄之², 坂内　博子¹ 1. 早稲田大学先進理工学研究科, 2. 慶應義塾大学医学部 Chisato Oyama¹, Sumihiro Maeda², Hideyuki Okano², Hiroko Bannai¹ 1. Waseda University, School of Advanced Science and Engineering, Tokyo, Japan, 2. Keio University, School of Medicine, Tokyo, Japan Tau protein is a microtubule-associated protein which localizes mainly in axons under physiological conditions but detaches from microtubules and aggregates in cell soma under pathological conditions. In this research, we aimed to understand the dynamics of endogenous tau in living neurons. Human iPS (hiPS) cell, in which endogenous tau was tagged with GFP (GFP-Tau), was differentiated into excitatory neurons by expressing Ngn2 and miR9/9*/124. By observing GFP signals in living neurons with Total Internal Reflection Fluorescence Microscope (TIFRM), we found that GFP-Tau clusters were actively transported at various velocities within neurons. We also examined the effect of tau mutations which cause familial neurodegenerative diseases. Among those mutations, we focused on A152T which toxicity is aggregation-independent and P301S which toxicity is aggregation-dependent. Both Tau mutants increased the velocity of GFP-Tau movement. Nocodazole, a microtubule-destabilizer, decreased the numbers of mobile GFP-Tau clusters, indicating that the movements of GFP-Tau are microtubule-dependent. Additionally, these GFP-Tau clusters were resistant to 1,6-Hexanediol, indicating that they were not formed through liquid-liquid phase separation. These results suggest that abnormalities in tau dynamics caused by tau mutations can be one of the pathogeneses of tauopathy.		7月6日（木）　13:20-14:20　ポスター会場① 1P⑤-4 脊髄小脳失調症の原因タンパク質は、共通して樹状突起縮小とタンパク質分解の障害を引き起こす Causing proteins for spinocerebellar ataxias commonly induce dendritic shrinkage and impairment of protein degradation 植田　恵梨香¹, 今野　歩², 平井　宏和², 倉内　祐樹¹, 香月　博志¹, 関　貴弘^1,3 1. 熊本大　院生命　薬物活性, 2. 群馬大　院医　脳神経再生, 3. 姫路獨協大　薬　薬理 Erika Ueda¹, Ayumu Konno², Hirokazu Hirai², Yuki Kurauchi¹, Hiroshi Katsuki¹, Takahiro Seki^1,3 1. Dept. Chemico-Pharmacol. Sci., Grad. Sch. Pharm. Sci., Kumamoto Univ. Spinocerebellar ataxia (SCA) is a group of autosomal-dominantly inherited ataxia and is classified into SCA1-49 by the difference in causal genes, whose mutations include polyglutamine (polyQ)-expanded and missense mutations. Purkinje cells (PCs) are neurons with highly developed dendrites and important for cerebellar functions. We have previously revealed that dendritic shrinkage and impairment of chaperone-mediated autophagy (CMA) and microautophagy (mA), which are protein degradation pathways, are observed in primary cultured PCs expressing missense mutant SCA14- and SCA21-causing proteins. In this study, we investigated the effects of other SCA-causing proteins, including polyQ-expanded (SCA1, 3, and 6) and missense (SCA34, 38, 41) mutants, on the dendritic morphology and CMA/mA activity in primary cultured PCs. Adeno-associated viral vectors were used for the expression of SCA-causing proteins in PCs of cerebellar primary cultures prepared from Wistar rat embryos. Compared with wild-type proteins, all SCA-causing proteins, including polyQ-expanded and missense mutants, triggered dendritic shrinkage and a decrease in CMA/mA activity in primary cultured PCs. These findings suggest that the impairment of CMA/mA is a possible common mechanism in SCA pathogenesis and leads to the dendritic shrinkage of primary cultured PCs, as a common in vitro phenotype for SCA.

7月6日（木）　13:20-14:20　ポスター会場① 1P⑤-5 精神科認知症コホートにおけるNOTCH2NLC遺伝子GGCリピート長の解析 Analysis of GGC repeat length of the NOTCH2NLC gene in a psychiatric-dementia cohort 宮本　哲愼, 森　康治, 魚住　亮太, 後藤　志帆, 近藤　志都子, 梅田　寿美代, 佐竹　祐人, 末廣　聖, 佐藤　俊介, 鐘本　英輝, 吉山　顕次, 赤嶺　祥真, 森原　剛史, 池田　学大阪大学大学院医学系研究科精神医学 Tesshin Miyamoto, Kohji Mori, Ryota Uozumi, Shiho Gotoh, Shizuko Kondo, Sumiyo Umeda, Yuto Satake, Takashi Suehiro, Shunsuke Sato, Hideki Kanemoto, Kenji Yoshiyama, Shoshin Akamine, Takashi Morihara, Manabu Ikeda Department of Psychiatry, Osaka University Graduate School of Medicine GGC repeat length in the 5' untranslated region of the Notch Homolog 2 N-terminal-like C (NOTCH2NLC) gene, which has been related to Neuronal Intranuclear Inclusion Disease (NIID), varies between individuals, with the number of repeats ranging from 3 to 30 in healthy individuals, while typically more than 70 in cases of NIID. Since at least some NIID cases are known to present with cognitive dysfunction, they may be clinically diagnosed with dementia for other reasons. Our psychiatric-dementia cohort collects genomic samples mainly from cases with dementia or cognitive impairment. We therefore investigated the possible presence of cases with pathological GGC repeat elongation in NOTCH2NLC in our cohort. GGC repeat length in the NOTCH2NLC was analyzed by Repeat-Primed PCR and Fluorescence Amplicon Length analysis. Abnormal elongation of GGC repeats in the NOTCH2NLC region was confirmed in one of the 600 cases analyzed. On retrospective review, this case did not show typical neuroimaging signs of NIID. Our study demonstrates that patient with abnormal repeat elongation in NOTCH2NLC is rare but can be found in a psychiatric-dementia cohort.