Generation of novel animal models for amyofrophic lateral sclerosis and studies on the molecular mechanisms underlying motor dysfunction

肌萎缩侧索硬化症新型动物模型的建立及运动功能障碍分子机制的研究

基本信息

批准号：
17300121
负责人：
HADANO Shinji
金额：
$ 10.3万
依托单位：
Tokai University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2007
项目状态：
已结题

项目摘要

Loss of function mutations in ALS2 account for a number of juvenile/infantile recessive motor neuron diseases, indicating that its gene product, ALS2, plays a crucial role in maintenance and survival for a subset of neurons. However, the normal physiological role of ALS2 in vivo and the molecular mechanisms underlying motor dysfunction are still unknown. To address these issues, we generated several lines of ALS2 transgenic mice and congenic lines of the Als2 knock-out (KO) mice in this study. Neither loss nor overexpression of ALS2 solely produced a severe disease phenotype in mice. However, when the Als2-KO mice was crossed with the SOD1R46R mouse line expressing familial ALS-linked SOD1H46R Als2-KO ; SOD1^<H46R>mice showed a much earlier motor dysfunction as well as a shorter life span than SODIH46R mice, suggesting that ALS2 plays a role in the onset and/or progression of motor neuron disease associated with mutant SOD1 in vivo. Next, to elucidate the neuronal ALS2 functions, we in … More vestigated cellular phenotypes of ALS2-deficient primary cultured neurons. ALS2 deficiency resulted not only in the delay of axon outgrowth in hippocampal neurons, but also in a decreased level of the macropinocytic activity in cortical neurons, suggesting that ALS2 acts as a modulator in neuronal differentiation and/or development through regulation of membrane dynamics. Finally, we investigated the molecular features of ALS2CL, a novel ALS2 homolog, and its functional relationship with ALS2. It was revealed that ALS2CL was a novel ALS2-interacting protein and was implicated in ALS2-mediated endosome dynamics. Collectively, our newly generated animals overexpressing and/or deleting ALS2 should provide invaluable research tools with which to understand the interplay between ALS2-mediated endosomal dynamics and the long-term viability of motor neurons in vivo. Further characterization of these mice will also clarify the implication of the ALS2-mediated neuronal functions in the pathogenesis for mutant SOD1-linkedALS. Less

ALS2 的功能缺失突变导致了许多青少年/婴儿隐性运动神经元疾病，表明其基因产物 ALS2 在神经元子集的维持和存活中发挥着至关重要的作用。为了解决这些问题，我们在体内和运动功能障碍的分子机制仍然未知，我们在本研究中产生了几个 ALS2 转基因小鼠品系和 Als2 敲除（KO）小鼠的同源品系。 ALS2 仅在小鼠中产生严重的疾病表型，然而，当 Als2-KO 小鼠与表达家族性 ALS 相关 SOD1H46R Als2-KO 小鼠系杂交时，SOD1^<H46R> 小鼠表现出更早的运动功能障碍。寿命比 SODIH46R 小鼠短，表明 ALS2 在与突变 SOD1 相关的运动神经元疾病的发生和/或进展中发挥作用接下来，为了阐明神经元 ALS2 的功能，我们研究了 ALS2 缺陷的原代培养神经元的细胞表型，ALS2 缺陷不仅导致海马神经元轴突生长延迟，而且导致巨胞饮水平降低。皮层神经元的活性，表明 ALS2 通过调节膜动力学在神经元分化和/或发育中发挥调节作用。新型 ALS2 同源物及其与 ALS2 的功能关系表明，ALS2CL 是一种新型 ALS2 相互作用蛋白，与 ALS2 介导的内体动力学有关。总的来说，我们新产生的过度表达和/或删除 ALS2 的动物应该提供宝贵的研究工具。以此来了解 ALS2 介导的内体动力学与体内运动神经元的长期活力之间的相互作用，这些小鼠的进一步表征也将阐明该影响。 ALS2 介导的神经元功能在突变 SOD1 相关 ALS 的发病机制中较少。