SWS/NTE function in neurodegeneration and axonopathy

描述(由申请人提供)：这项建议的目的是深入了解人类神经退行性疾病的基本机制，使用果蝇作为一个易于访问的模型系统。本申请的主题是一种名为瑞士奶酪(SWS)的果蝇突变体。SWS显示成人神经系统进行性退化。SWS是人类神经病变靶标酯酶(NTE)的功能同源基因，NTE是有机磷诱导的迟发性神经病(OPIDN)的明显分子靶点。OPIDN是一种远端轴索病变，类似于与年龄、遗传、代谢和中毒相关的大量其他周围神经病变。此外，最近的数据表明，NTE在小鼠中的神经元特异性敲除也会导致神经退化。尽管NTE已经被研究了20年，每年发生多达50万起由杀虫剂或神经毒剂引起的有机磷(OP)中毒事件，但人们对这种重要蛋白质的生物学功能一无所知。因此，本项目旨在进一步研究SWS的特征，并确定其在神经退行性变和轴索病变中所起的作用。果蝇揭示了神经退行性变的表型，并提供了一个易于访问的模型系统。尤其是利用小鼠进行的遗传学研究并不容易、可行，而且酵母和秀丽线虫的基因敲除也没有揭示出表型。本提案中概述的研究重点是蛋白质结构域和生物底物的识别和表征。此外，SWS功能的途径将通过分子和遗传方法(表达不同结构的苍蝇的创造和功能分析、双杂交筛选和遗传相互作用筛选)来阐明。功能分析将最终导致对SWS的生理功能以及为什么需要它来防止轴突变性和神经细胞死亡的理解。深入了解SWS的正常功能有助于更好地计划未来的研究，以了解NTE参与OP毒性和OPIDN在人类中的作用。

DESCRIPTION (provided by applicant): The purpose of this proposal is to gain insight into the basic mechanisms underlying human neurodegenerative disease using Drosophila as a readily accessible model system. The subject of the present application is a Drosophila mutant called swiss-cheese (sws). SWS shows progressive degeneration of the adult nervous system. SWS is the functional ortholog of human Neuropathy Target Esterase (NTE), the apparent molecular target in organophosphate-induced delayed neuropathy (OPIDN). OPIDN is a distal axonopathy similar to a large number of other peripheral neuropathies associated with age-related, genetic, metabolic and toxic conditions. In addition, recent data suggest that, a neuronal specific knock-out of NTE in mice also causes neurodegeneration. Although NTE has been studied for 20 years and as many as 500,000 cases of organophosphate (OP) poisoning through pesticides or nerve agents occur each year, nothing is known about the biological function of this important protein. Therefore, this project aims to further characterize SWS and determine the role it plays in neurodegeneration and axonopathy. Drosophila reveals the neurodegenerative phenotype and provides an easy accessible model system. Especially genetic studies using mice are not easy feasible and yeast and Caenorhabditis elegans knock-outs do not reveal a phenotype. The studies outlined in this proposal focus on the identification and characterization of protein domains and the biological substrate. addition, the pathways in which SWS functions will be elucidated by molecular and genetic approaches (creation and functional analysis of flies expressing different constructs, two-hybrid screens and genetic interaction screens). The functional analysis will eventually lead to an understanding of the physiological function of SWS and why it is required to prevent axonal degeneration and neural cell death. An insight into the normal function of SWS can then help to better plan future studies to understand the involvement of NTE in OP toxicity and OPIDN in humans.