Tau Isoform Expression in FTDP-17

FTDP-17 中的 Tau 同工型表达

• 批准号: 6540426
• 负责人: VIVIANNA M VAN DEERLIN
• 金额: $ 13.12万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-15 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6540426
• 关键词: RNA splicing; cell population study; chromosomes; complementary DNA; dissection; gene expression; gene mutation; glia; human tissue; messenger RNA; microarray technology; neurogenetics; neurons; phenotype; phosphorylation; polymerase chain reaction; protein isoforms; protein structure function; tau proteins; tissue /cell culture

DESCRIPTION (provided by applicant): Filamentous aggregates of hyperphosphorylated tau are the signature brain lesions of frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP 17), an inherited tauopathy with diverse, phenotypes caused by different tau gene mutations. Tau is a microtubule (MT) binding protein that promotes tubulin polymerization into MTs and stabilizes MTs. The adult human brain contains six tau isoforms, half with 3 3R isoforms) and half with 4 Cterminal MTbinding repeats (4R isoforms) generated by alternatively splicing of exon 10 (E 10). Tau gene mutations cause FTDP 17 by impairing E 10 alternative splicing or tau functions. A puzzling aspect of the FTDP 17 syndromes is that different tau mutations damage selected subtypes of neurons and glia. Our first hypothesis is that this selective vulnerability may reflect cell type specific perturbations of tau isoforms to cause varied phenotypes. To test this hypothesis, we will determine mRNA expression profiles of tau isoforms in normal brain cell subpopulations. Although the ratio of 3R to 4R tau is 1:1 in normal human brain, it has never been determined in subpopulations of neurons and glia. In, Aim 1, we will microdissect neurons and glia from paraffinembedded tissue sections of control brains, perform linear amplification on extracted RNA followed by quantitative realtime RTPCR to measure the relative levels of each tau isoform mRNA. In Aim 2, we will similarly study the same neuronal and glial cell populations in FTDP 17 brains. Correlation of these data with disease phenotypes will clarify mechanisms of FTDP1 7. Since FTDP1 7 mutations produce different phenotypes in the same kindred, a second hypothesis proposes that altered expression of a second gene, which interacts with the tau gene or protein, influences development of phenotypic manifestations of FTDP 17 in different affected family members. Aim 3 tests this hypothesis by examining the differential expression of candidate genes (i.e. those involved in splicing, RNA stability, tau function, other cellular processes) between affected and unaffected FTDP 17 brain regions and control brains using custommade cDNA macroarrays. The completion of these Aims will advance understanding of FTDP 17 and related tauopathies, and may provide new targets for diagnosis and therapeutics.

描述（由申请人提供）： 丝状聚集体 过度磷酸化的 tau 蛋白是额颞叶的标志性脑损伤 与 17 号染色体相关的帕金森病痴呆症 (FTDP 17)，一种遗传性疾病 由不同 tau 基因突变引起的具有多种表型的 tau 病。牛头蛋白 是一种微管 (MT) 结合蛋白，可促进微管蛋白聚合成 MT 和稳定 MT。成人大脑含有六种 tau 亚型，其中一半 具有 3 个 3R 同工型），一半具有 4 个 C 末端 MT 结合重复序列（4R 同工型） 由外显子 10 (E 10) 的选择性剪接生成。 Tau基因突变导致 FTDP 17 通过损害 E 10 选择性剪接或 tau 功能。一个令人费解的 FTDP 17 综合征的一个方面是不同的 tau 突变会损害所选的 神经元和神经胶质细胞的亚型。我们的第一个假设是，这种选择性 脆弱性可能反映了 tau 异构体的细胞类型特异性扰动 导致不同的表型。为了检验这个假设，我们将确定 mRNA 正常脑细胞亚群中 tau 亚型的表达谱。 虽然正常人脑中3R与4R tau的比例为1:1，但从未 已在神经元和神经胶质细胞亚群中确定。在目标 1 中，我们将 从对照的石蜡包埋组织切片中显微解剖神经元和神经胶质细胞 大脑，对提取的 RNA 进行线性扩增，然后进行定量 实时 RTPCR 测量每种 tau 亚型 mRNA 的相对水平。瞄准 2、我们将类似地在 FTDP 中研究相同的神经元和神经胶质细胞群 17个大脑。这些数据与疾病表型的相关性将阐明 FTDP1 7 的机制。由于 FTDP1 7 突变在 同一个家族，第二个假设提出，改变了a的表达 第二个基因与 tau 基因或蛋白质相互作用，影响 FTDP 17 在不同受影响人群中表型表现的发展 家庭成员。目标 3 通过检查差异来检验这一假设 候选基因的表达（即那些参与剪接、RNA稳定性、 受影响和未受影响的 FTDP 17 之间的 tau 功能、其他细胞过程） 使用定制的 cDNA 宏阵列分析大脑区域并控制大脑。这 完成这些目标将促进对 FTDP 17 及相关内容的理解 tau蛋白病，并可能为诊断和治疗提供新的靶点。