MODULATION OF APP METABOLISM BY X11ALPHA/MINT-1

X11ALPHA/MINT-1 对 APP 代谢的调节

• 批准号: 6933390
• 负责人: RAYMOND SCOTT TURNER
• 金额: $ 12.5万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6933390
• 关键词: Alzheimer' s disease; amyloid proteins; brain metabolism; cell line; gene expression; genetically modified animals; human tissue; immunocytochemistry; in situ hybridization; laboratory mouse; neuritic plaques; neuropathology; postmortem; presenilin; protein localization; protein metabolism; protein protein interaction; protein transport

The neuronal adaptor protein X11alpha/mint-1 interacts with amyloid precursor protein (APP) to regulate its trafficking and processing in vitro. In transfected non-neuronal cells, X11alpha inhibits alpha- and gamma- but not beta- cleavage of APP. Because the phosphotyrosine binding (PTB) domain of X11alpha interacts specifically with the APP family, X11alpha appears to inhibit gamma-cleavage of APP specifically while sparing gamma-cleavage of Notch and other substrates of regulated intramembranous proteolysis. To determine the in vivo significance of these in vitro data, we will generate and characterize novel hX11alpha transgenic mice and X11alpha knockout mice and examine murine APP metabolism. Crosses of these mice to Tg2576 mice (transgenic for the Swedish mutation of hAPP, or hAPPswe) will probe the effects of XI la on hAPPswe metabolism and on the development of partial AD-like phenotypes in aging brain. A recent human genome-wide analysis revealed significant linkage of sporadic AD to single nucleotide polymorphisms (SNPs) on chromosome 9, perhaps including the X11alpha region. We will probe genetic linkage of SNPs in the X11alpha region to sporadic AD by using genomic DNA extracted from samples from AD subjects versus carefully-matched control subjects. The specific aims are to: 1) generate X11alpha knockout and hX11alpha transgenic mice and determine effects on murine APP metabolism in brain and in primary neuronal cultures, 2) cross X11alpha knockout and hX11alpha transgenic mice with Tg2576 mice to determine a) modulatory effects on hAPPswe metabolism in brain and in neuronal cultures, and b) development of AD-like phenotypes with aging, and 3) elucidate the SNPs and haplotypes within or adjacent to the X11alpha gene of AD cases and age-, gender-, and ApoE-matched controls to determine if there is a statistically significant link to sporadic AD. Specific aim 3 will study DNA samples obtained from the Pathology Core and from other ADRCs. These results will 1) inform the normal functions of X11alpha as well as APP and its derivatives in CNS neurons, 2) lay the groundwork for viral-vector based gene therapy of AD using either X11alpha or its PTB domain in hAPP transgenic mouse models, and 3) probe a potential genetic risk factor of sporadic AD.

神经元衔接蛋白X11Alpha/Mint-1与淀粉样蛋白前体蛋白（APP）相互作用，以调节其体外运输和加工。在转染的非神经元细胞中，X11Alpha抑制APP的α-和γ-但不抑制β。由于X11Alpha的磷酸酪氨酸结合（PTB）结构域特异性相互作用，因此X11Alpha似乎特异性地抑制了APP的伽马 - 裂解，同时又节省了Notch的γ-裂解和其他受调控性内膜内蛋白质分析的粘液液。为了确定这些体外数据的体内意义，我们将生成和表征新型的HX11ALPHA转基因小鼠和X11Alpha敲除小鼠，并检查鼠类应用的代谢。这些小鼠的杂交将其交叉到TG2576小鼠（Happ或Happswe的瑞典突变的转基因）将探测Xi La对Happswe代谢的影响以及对衰老大脑中部分AD样表型的发展。最新的人类基因组分析表明，散发性AD与9号染色体上的单核苷酸多态性（SNP）的显着联系，可能包括X11Alpha区域。 我们将通过使用从AD受试者的样品中提取的基因组DNA与仔细匹配的对照受试者提取的基因组DNA，将SNP探测为X11Alpha区域中SNP的遗传连接。 The specific aims are to: 1) generate X11alpha knockout and hX11alpha transgenic mice and determine effects on murine APP metabolism in brain and in primary neuronal cultures, 2) cross X11alpha knockout and hX11alpha transgenic mice with Tg2576 mice to determine a) modulatory effects on hAPPswe metabolism in brain and in neuronal cultures, and b) development of具有衰老的AD样表型，以及3）阐明了AD病例和年龄，性别 - 和APOE匹配的对照的X11Alpha基因内部或附近的SNP和单倍型，以确定是否存在与散发性AD的统计学意义。特定目标3将研究从病理核心和其他ADRC获得的DNA样品。这些结果将为1）通知正常功能 X11Alpha以及CNS神经元中的APP及其衍生物，2）在HAPP转基因小鼠模型中使用X11Alpha或其PTB结构域为基于病毒载体的基因治疗奠定了基础，并在HAPP转基因小鼠模型中为AD奠定基础，3）探测孢子虫AD的潜在遗传风险因素。