RAFT-LIKE TRANSPORT OF CYTOSKELETAL ELEMENTS IN MAMMALS

神经元的独特形态需要主动转运机制来适当和及时地递送新合成的蛋白质，然而主动转运给神经元带来了必须发展和维持细胞骨架轨道以进行定向运动的负担。来自莱茵衣藻的证据表明，在鞭毛内运输（IFT）过程中，运动蛋白II与大的筏状结构有关。最近克隆的NGD5是衣藻IFT raft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和激酶II是否属于哺乳动物中用于运输细胞骨架成分的类似系统的成员。共定位和共免疫沉淀将针对特定的神经元群体进行进一步、更详细的分析。最终，研究人员将利用NGD5和激酶II靶向基因破坏神经元的运输和结构分析来直接验证这一假设。有证据表明，神经丝的错误积累可导致肌萎缩侧索硬化症（ALS）样病理。此外，轴突转运的减缓是与als相关的SOD 1突变毒性相关的早期事件。因此，对蛋白质转运机制的理解是我们理解神经系统的基础，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.