RAFT-LIKE TRANSPORT OF CYTOSKELETAL ELEMENTS IN MAMMALS

神经元的独特形态需要主动运输机制来适当和及时地递送新合成的蛋白质，然而主动运输给神经元带来了必须发展和维持定向运动的细胞骨架轨道的负担。来自莱茵衣藻的证据表明，驱动蛋白II与鞭毛内运输（IFT）过程中的大型筏状结构相关。最近克隆NGD5，衣原体IFT筏成员的同源物，提出了在哺乳动物中利用类似系统的可能性。为了测试NGD5和驱动蛋白II是否是哺乳动物中用于运输细胞骨架组分的类似系统的成员，提出了。共定位和免疫共沉淀将靶向特定的神经元群体，用于进一步的更详细的分析。最终，将利用NGD5和驱动蛋白II的靶向基因破坏对神经元中的运输和结构的分析来直接检验该假设。有证据表明，神经丝的错误积聚可导致肌萎缩侧索硬化症（ALS）样病理。此外，轴突运输的减慢是与ALS连锁的SOD 1突变的毒性相关的早期事件。因此，了解蛋白质转运的机制对我们了解神经系统至关重要，并可能为神经退行性疾病的发病机制提供见解。

The distinct morphology of neurons requires active transport mechanisms for the appropriate and timely delivery of newly synthesized proteins, yet active transport places the burden on neurons of having to develop and maintain cytoskeletal tracks for directed locomotion. Evidence from Chlamydomonas reinhardtii indicates that kinesin II associates with large, raft-like structures during intraflagellar transport (IFT). The recent cloning of NGD5, a homologue of a member of Chlamydomonas IFT rafts, raises the possibility that an analogous system is utilized in mammals. To test if NGD5 and kinesin II are members of an analogous system in mammals utilized for transporting cytoskeletal components is proposed. Colocalization and coimmunoprecipitation will target specific neuronal population for further, more detailed analysis. Ultimately, analysis of transport and structure in neurons with targeted gene disruptions of NGD5 and kinesin II will be utilized to directly test the hypothesis. Evidence indicates that the misaccumulation of neurofilaments can lead to amyotrophic lateral sclerosis (ALS)-like pathology. Additionally, slowing of axonal transport is an early event associated with the toxicity of ALS-linked SOD 1 mutations. Therefore, an understanding of the mechanisms involved in protein transport is fundamental to our understanding of the nervous system and may provide insight into the pathogenesis of neurodegenerative diseases.