Building Synaptic Cytoskeleton

肌动蛋白细胞骨架锚定突触粘附分子，并产生灵活的结构， 具有树突棘的形状。它调节和支持膜交通和定义突触 隔间它还驱动新突触的产生以及突触大小和形状的持久变化 是对显著刺激的反应这些都是长期存在的、被广泛接受的事实。广大 这些事实的接受使人们更加惊讶的是，人们对突触肌动蛋白 生成。当新的突触形成时，是什么驱动它的组装，这个过程与 是脊柱扩张还是萎缩的原因这种知识上的差距限制了对 阿尔茨海默氏病和相关痴呆症，其中突触丢失和脊柱形状的变化很好， 记录在案。它还影响大脑疾病和病理，包括肌萎缩性侧索硬化症， 精神分裂症、智力残疾和自闭症，这些疾病都可能与肌动蛋白的突变、缺失或获得有关。 调节功能，以及涉及突触可塑性脱轨机制的疾病，如药物 成瘾这种知识上的差距不是疏忽或缺乏兴趣造成的。它的存在是因为突触 肌动蛋白丝很小，很难研究，它非常细、脆弱、动态， 对于成核肌动蛋白重要的组分最近才被鉴定。这项建议的目的是 确定与突触产生相关的主要肌动蛋白成核剂，并评估时间、地点和 他们行动的背景。不知道相关参与者是该领域的一个限速步骤， 实验是确定肌动蛋白支架的性质和位置的第一步， 突触形成的阶段、生物学作用（例如粘附或运输）或状态变化（例如， 增强或抑制）。

The actin cytoskeleton anchors synapse adhesion molecules and generates the flexible architecture that characterizes dendritic spine shape. It regulates and supports membrane traffic and defines synapse compartments. It also drives the generation of new synapses and lasting changes in synapse size and shape that occur in response to salient stimuli. These are long-standing, widely accepted facts. The broad acceptance of these facts makes it all the more surprising that relatively little is known about how synaptic actin is generated. What drives its assembly when new synapses are forming, and how does this process differ from the reorganization that drives spine expansion or shrinkage? This gap in knowledge limits the understanding of Alzheimer's Disease and related dementias where synapse loss and changes in spine shape are well documented. It also impacts brain disorders and pathologies, including amyotrophic lateral sclerosis, schizophrenia, intellectual disability and autism, that can be seeded in the mutation, loss, or gain of actin regulatory function, and disorders that involve derailed mechanisms of synapse plasticity such as drug addiction. This gap in knowledge is not an oversight or due to lack of interest. It exists because synapses are small and difficult to study, actin filaments are exceptionally thin, fragile and dynamic, and several molecular components important for nucleating actin have only recently been identified. The purpose of this proposal is to identify the principal actin nucleators relevant to the generation of synapses, and to assess the time, place, and context in which they act. Not knowing the relevant players is a rate limiting step in the field and the proposed experiments are a first step toward identifying the nature and location of actin scaffolds relevant to particular stages of synapse formation, biological actions (e.g. adhesion or trafficking) or to changes in state (e.g. potentiation or depression).