The role of the secretory pathway in ethanol-induced neural tissue injury

描述(由申请人提供)：神经元树突的损伤是酒精引起的神经损伤的关键组成部分。然而，乙醇诱导的树枝晶缺陷的机制却知之甚少。如果我们想要了解酒精对神经元发育的影响，并设计防止酒精对发育中的神经元造成损害的策略，这些机制的知识是必不可少的。我们的长期目标是确定树突和轴突发育的潜在机制，并确定树突和轴突缺陷如何导致人类疾病。这项拟议的研究的目的是描述乙醇诱导的树枝晶生长缺陷的机制。以前的研究已经证明了分泌途径在树突发育中的重要性。虽然乙醇在各种类型的细胞中引起内质网应激，但它对内质网和高尔基体的影响却知之甚少，而内质网和高尔基体是膜和分泌蛋白的运输和糖基化以及细胞信号传递的关键。申请者已经建立了一种独特的系统，该系统在遗传上容易处理，用于研究果蝇的神经分泌途径。中心假设是乙醇诱导的内质网应激导致内质网重组和高尔基体碎裂，从而减少树突状细胞的生长。这一假设是基于申请人实验室的初步发现。这一假说将通过追求两个特定的目标来验证：1)确定乙醇诱导的神经元内质网和高尔基体缺陷的机制；2)确定乙醇诱导的树突生长缺陷的机制。在第一个目标下，基因技术和细胞生物学测试将被应用于描述内质网应激和相关的作用，这些技术已经在申请人的实验室中被确立为可行的。 乙醇对内质网和高尔基体缺陷的反应。在第二个目标下，申请人将利用他在分析树枝晶发育方面的专业知识来描述内质网应激和高尔基碎裂在乙醇诱导的树枝晶生长中的作用。这项拟议的研究结果有望确定乙醇、分泌途径和树突发育之间的因果关系。这种方法是创新的，因为它将一种遗传上易于处理的体内系统引入了乙醇对细胞细胞器的研究中，事实证明，这种系统在细胞生物学问题的分子和遗传分析方面是强大的。这项拟议的研究具有重要意义，因为它将填补我们对乙醇对分泌途径影响的了解的空白，并导致对乙醇诱导的树突发育的机制理解。它还将建立一个体内系统，用于识别阻止乙醇引起的分泌途径和神经发育损伤的化合物。因此，这不仅将为广泛研究乙醇对细胞器的作用奠定基础，也将为开发治疗乙醇引起的发育缺陷的策略奠定基础。

DESCRIPTION (provided by applicant): Damage to neuronal dendrites is a key component of ethanol-induced neural injury. However, the mechanisms underlying ethanol-induced dendrite defects are poorly understood. Knowledge of these mechanisms is essential if we are to understand the effects of alcohol on neuronal development and design strategies for preventing the damaging effects of ethanol on developing neurons. Our long-term goals are to define the mechanisms underlying dendrite and axon development and to determine how defects in dendrites and axons lead to human diseases. The objective of the proposed research is to delineate the mechanisms underlying ethanol-induced dendrite growth defects. Previous studies have demonstrated the importance of the secretory pathway in dendrite development. Although ethanol is known to cause ER stress in various cell types, its effects on ER and Golgi, which are pivotal for the trafficking and glycosylation of membrane and secreted proteins and for cellular signaling, is much less understood. The applicant has established a unique system that is genetically tractable for studying the neuronal secretory pathway in Drosophila. The central hypothesis is that ethanol-induced ER stress leads to ER reorganization and Golgi fragmentation and consequently reduces dendritic growth. This hypothesis is based on preliminary findings from the applicant's laboratory. This hypothesis will be tested by pursuing two specific aims: 1) Identify the mechanism underlying ethanol-induced ER and Golgi defects in neurons; 2) Identify the mechanism underlying ethanol-induced dendrite growth defects. Under the first aim, genetic techniques and cell biological assays, which have been established as feasible in the applicant's lab, will be applied to delineate the roles of ER stress and related responses in ethanol-induced defects in ER and Golgi. Under the second aim, the applicant will take advantage of his expertise in analyzing dendrite development to delineate the roles of ER stress and Golgi fragmentation in ethanol-induced dendrite growth. The results of the proposed research are expected to define a causal relationship among ethanol, the secretory pathway, and dendrite development. The approach is innovative because it introduces a genetically tractable in-vivo system proven to be powerful for molecular and genetic analysis of cell biological problems into ethanol research on cellular organelles. The proposed research is significant because it will fill the gap in our understanding of ethanol effects on the secretory pathway and lead to a mechanistic understanding of ethanol-induced dendrite development. It will also establish an in-vivo system for identifying compounds that block ethanol-induced damage on the secretory pathway and neural development. Thus, it will lay the ground not only for extensive investigation of the role of ethanol on cellular organelles, but also for developing therapeutic strategies to cure ethanol-induced developmental defects.