TAU PATHOLOGY AND SYNAPTIC MESSAGE IN ALZHEIMERS

描述：（申请人的摘要）：突触的丧失是 目前似乎与老年痴呆症的程度最相关， 阿尔茨海默病（AD）。 基于细胞骨架的破坏 随着神经元缠结（NFT）的形成，以及它们的成分， “异常”磷酸化的tau蛋白，我们假设具有NFT的神经元， 而不是它们相邻的无缠结神经元， 负责这种突触的损失（无论这是在神经元死亡之前 仍然是一个悬而未决的问题）。 我们在这个提案中的重点是测试假设 相关的影响（或缺乏）的NFT和tau磷酸化， 不同的网站（和网站的组合）对信息的表达 与突触和神经元功能相关：突触素、GAP-43、热 休克蛋白，组织蛋白酶。 Tau有21个潜在的磷酸化位点。 我们提出的研究是由tau函数模型驱动的，其中 微管结合域（重复区）被“钳口”包围 对微管的tau促进有重要贡献的区域 组装件. 我们将使用原位杂交技术检测突触素和其他 选择信息来确定单个神经元的分子状态 结合双重免疫细胞化学（ICC）来定义神经元的类别。 我们将比较来自神经元类的单个神经元的颗粒计数 通过抗体组合揭示：三大类神经元将 出现在AD脑中：1）具有NFT（磷酸化tau在这些脑中也可能是明显的。 神经元），2）没有NFT，但在确定的位点有磷酸化tau， 位点的组合，和3）既不是NFT也不是磷酸化tau。 神经元没有 NFT或磷酸化tau的证据将从对照脑中取样。 无疾病对照和AD脑切片将在 相同的切片进行定量比较。 一般的假设是 测试，简要地说： 假设一：NFT的神经元将减少蛋白质的信息 相关的突触结构和功能以及生长锥。 假设II：“颚”区域中的Tau磷酸化将具有更大的 对突触和应激相关信息表达的影响 tau蛋白磷酸化在Ser 262的重复，微管结合区， τ的 假设III：具有NFT或异常磷酸化tau蛋白的神经元将具有 与细胞应激相关的蛋白质的信息水平增加。 假设四：AD大脑中将有“未受影响”的神经元， 测量将不能与对照脑中的同源神经元区分开。

DESCRIPTION: (Applicant's abstract): Loss of synapses is the variable that currently appears to correlate best with the degree of dementia in Alzheimer's disease (AD). Based on the cytoskeletal disruption associated with the formation of neurofibrillary tangles (NFT), and their constituent, "abnormally" phosphorylated tau, we hypothesize that neurons with NFT, rather than their adjacent tangle-free neurons, are at least partially responsible for this loss of synapses (whether this precedes neuron death remains an open question). Our focus in this proposal is to test hypotheses related the effects(s) (or lack thereof) of NFT and of tau phosphorylated at different sites (and combinations of sites) on the expression of messages related to synaptic and neuronal function: synaptophysin, GAP-43, heat shock proteins, cathepsins. Tau has 21 potential phosphorylation sites. The studies we propose are driven by a model of tau function in which the microtubule binding domain (the repeat region) is surrounded by "jaws" regions which make important contributions to tau promotion of microtubule assembly. We will use in situ hybridization for synaptophysin and other selected messages to determine the molecular status of single neurons combined with double immunocytochemistry (ICC) to define classes of neurons. We will compare grain counts over single neurons from the classes of neurons revealed by antibody combinations: Three general classes of neurons will appear in AD brain: 1) with NFT (phospho-tau may also be apparent in these neurons), 2) without NFT but with phospho-tau at defined sites and combinations of sites, and 3) neither NFT nor phospho-tau. Neurons without evidence of NFT or phospho-tau will be sampled from control brain. Disease-free control and AD brain sections will be processed side-by-side on the same slides for quantitative comparison. The general hypotheses to be tested are, briefly: Hypothesis I: Neurons with NFT will have decreased message for proteins related synaptic structure and function and the growth cone. Hypothesis II: Tau phosphorylation in the "jaws" region will have a greater influence on expression of synaptic and stress related messages than will tau phosphorylation at Ser 262 in the repeat, microtubule binding region of tau. Hypothesis III: Neurons with NFT or abnormally phosphorylated tau will have increased levels of message for proteins related to cellular stress. Hypothesis IV: There will be "unaffected" neurons in AD brain that our measures will not distinguish from homologous neurons in control brain.