ATM SIGNALING AND NEURODEGENERATION

ATM单基因突变导致隐性共济失调 毛细血管扩张(AT)。AT是一种多系统疾病，其特征是 进行性神经变性，免疫缺陷，肿瘤易感性， 性腺萎缩和辐射敏感。ATM基因的最新克隆 使研究多效性效应的基础成为可能。 自动取款机。 使用几种针对ATM的多克隆和单克隆抗体 蛋白质产品，我们已经证明了ATM蛋白质产品是 主要是一种核磷蛋白，是一种真正的蛋白激酶， 并与几个潜在的下游效应器相关联，包括 非受体酪氨酸激酶和DNA重组/修复蛋白。 在所有症状中，神经变性对患者的破坏性最大 与AT。拟议研究的目标是确定这种机制。 通过这些ATM下游效应器提高神经元存活和 建立未来自动取款机干预模式体系 神经退行性变。它有两个具体目标：1.分子分析 ATM诱导的信号事件是神经元生存所必需的。我们会 首先解决ATM的效应者之一c-abl和NF-kB是否发挥作用 神经细胞系和原代细胞在神经退行性变中的作用 小脑培养。为了确定更多的信号通路，我们将 在神经细胞中表达ATM的显性抑制形式 表征可能与之相关的磷酸化事件 ATM缺陷细胞的神经变性。我们亦会研究 ATM在细胞周期和DNA损伤时的细胞定位 使用绿色荧光蛋白和ATM融合蛋白。我们会 鉴定神经细胞中ATM信号通路的新成分 使用多种方法检测ATM相关蛋白。最后， 将研究已知突变的原代小鼠胚胎成纤维细胞 确定ATM与其他设备之间的调节器和效应器关系 特定的蛋白质。2.ATM中神经元-神经胶质细胞相互作用的研究 介导的神经退行性变与抗细胞凋亡的保护作用 基因。动物模型将被用来测试是否有进步 神经退行性变表现为神经元和神经胶质细胞的缺陷。 细胞。促进细胞存活的基因产品是否能阻止疾病 进展将接受测试。

Mutations of a single gene, ATM, cause the recessive disorder ataxia telangiectasia (AT). AT is a multisystem disease characterized by progressive neurodegeneration, immunodeficiency, tumor susceptibility, gonadal atrophy, and radiosensitivity. Recent cloning of the ATM gene has made it possible to study the basics of the pleiotropic effects of ATM. Using several polyclonal and monoclonal antibodies specific for ATM protein product, we have demonstrated that the ATM protein product is predominantly a nuclear phosphoprotein, is an authentic protein kinase, and is associated with several potential downstream effectors including a non-receptor tyrosine kinase and DNA recombination/repair proteins. Among all symptoms, neurodegeneration is most devastating to patients with AT. The goal of the proposed studies is to determine the mechanism by which these downstream effectors of ATM enhance neuronal survival and to establish model systems for future intervention of ATM-mediated neurodegeneration. There are two specific aims: 1. Molecular analysis of ATM-induced signaling events required for neuronal survival. We will first address whether one of the effectors of ATM, c-abl and NF-kB, play a role in neurodegeneration using neuronal cell lines and primary cerebellar cultures. To identify additional signal pathways, we will express dominant-inhibitory forms of ATM in neuronal cells to characterize the phosphorylation events that may be linked to neurodegeneration in ATM-deficient cells. We will also study the cellular localization of ATM during the cell cycle and upon DNA damage using the green fluorescent protein and ATM fusion protein. We will identify new components of ATM signaling pathways in neuronal cells using multiple approaches to detect ATM-associated proteins. Finally, primary mouse embryonic fibroblasts with known mutations will be studied to confirm the regulator and effector relationship between ATM and other specific proteins. 2. Studies of neuron-glial cell interaction in ATM- mediated neurodegeneration and protective effects of anti-apoptotic genes. Animal models will be used to test if progressive neurodegeneration is manifested by defects in both neuronal and glial cells. Whether gene products that promote cell survival thwart disease progression will be tested.