Elucidation of molecular mechanisms of amyotrophic lateral sclerosis

本研究旨在阐明肌萎缩侧索硬化症（ALS）神经退行性变的分子机制，并进一步发展ALS的治疗策略。该项目集中在1。家族性ALS患者Cu/Zn SOD基因突变的详细分析; 2.突变Cu/Zn SOD蛋白构象变化分析; 3.创建家族性ALS的转基因小鼠。在33个家族性ALS家系中，我们发现了7个SOD 1基因突变，其中包括3个新突变（Ala 4Thr，Cys 111 Tyr和Glu 133 Stop）。通过在COS细胞中瞬时表达突变型Cu/Zn SOD蛋白，我们发现突变型Cu/Zn SOD蛋白具有聚集体形成和SDS-PAGE分析的迁移率改变的特性，支持突变型蛋白具有构象改变。我们已经建立了转基因小鼠品系携带Ala 4Thr和Ile 113 Thr，其中Ile 113 Thr小鼠已开发的后腿肌肉无力。基于本项目所取得的成果，将进一步研究突变型Cu/Zn SOD蛋白引起的神经退行性变的分子机制。

This research was aimed to elucidate molecular mechanisms of neurodegeneration in amyotrophic lateral sclerosis (ALS), and, furthermore, to develop therapeutic strategies for ALS. The project focused on 1. detailed mutational analysis of Cu/Zn SOD gene in familial ALS, 2. analysis of conformational changes of mutant Cu/Zn SOD proteins, and 3. creation of transgenic mice for familial ALS. Among 33 families with familial ALS, we have identified 7 mutations in the SOD1 gene including 3 novel ones (Ala4Thr, Cys111Tyr and Glu133Stop). By transient expression of mutant Cu/Zn SOD proteins in COS cells, we have found that the mutant Cu/Zn SOD proteins possesses properties for aggregate formation and altered mobility on SDS-PAGE analysis, supporting that the mutant proteins have conformations changes. We have established transgenic mouse lines carrying Ala4Thr and Ile113Thr, of which Ile113Thr mice have developed muscular weakness in the hindlegs. Based on the accomplishments obtained through this project, molecular mechanisms of neurodegeneration caused by mutant Cu/Zn SOD proteins will further be investigated.