Identification of posttranslational modification of the tau in paired helical filaments

成对螺旋丝中 tau 蛋白翻译后修饰的鉴定

• 批准号: 03102008
• 负责人: IHARA Yasuo
• 金额: $ 70.4万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Specially Promoted Research
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03102008/
• 关键词: Alzheimer's disease; Paired helical flaments; tau; phosphorylation; proline-directed protein kinase; ubiquitin; アルツハイマ-病; Alzheimer′s disease; Paired helical filaments; Phosphorylation; Ubiquitination; Fragmntation

Paired helical filaments (PHF) are closely related to neuronal death and thus their complete elucidation should lead us to understanding of particular intracellular environmental alterations that cause neurons to die. I focused on the abnormal phosphorylation of PHF-tau because the phosphorylation could precede the PHF formation.Two phosphorylation-dependent PHF polyclonals and two PHF monoclonals each of which has distinct specificity has been shown to recognize fetal tau but not adult tau. This observation led us to determine the phosphorylation sites in fetal tau as a first step. Fetal tau bears at most ten covalently bound phosphates, eight of which are proline-directed. The phosphorylation sites are roughly equal to those phosphorylated by cdk5 and GSK3beta. Two non proline-directed phosphorylated sites are found to be indeed the motifs for GSK3beta, when downstream proline-directed sites are phosphorylated.We next attempted to determine the phosphorylation sites in PHF in a simil … More ar way. Major difficulaties were unusual resistance to many specific proteases and very poor recovery of phosphopeptides from a HPLC column, which was never experienced in fetal tau. PHF-tau is phosphorylated at most twenty One sites ; Ten are proline-directed, while eleven are non proline-directed. Most of the sites phosphorylated in fetal tau are also phosphorylated in PHF-tau, which explains those immunochemical similarities between PHF-tau and fetal tau. Overall, the phosphorylation of PHF can be considered to consist of fetal-type phosphorylation plus additional proline-directed and non proline-directed phosphorylation. Some of those non proline-directed sites correspond to the sites phosphorylated by cAMP-dependent protein kinase (PKA). Thus, the phosphorylation of PHF-tau would be mediated by multiple kinases, cdk5, GSK3beta, and possibly PKA.Those non proline-directed phosphorylation which distinguish PHF-tau from fetal tau may be important to the unusual characteristics of PHF-tau, including its assembly incompetence and protease resistance. Less

成对螺旋丝（PHF）与神经元死亡密切相关，因此它们的完整阐明应使我们了解导致神经元死亡的特定细胞内环境改变。由于PHF-tau的磷酸化可能先于PHF的形成，因此我将重点放在了PHF-tau的异常磷酸化上，两个磷酸化依赖的PHF多克隆和两个PHF单克隆都具有不同的特异性，它们可以识别胎儿tau而不能识别成人tau。这一观察结果使我们确定胎儿tau蛋白中的磷酸化位点作为第一步。胎儿tau携带最多十个共价结合的磷酸盐，其中八个是脯氨酸导向的。磷酸化位点与cdk 5和GSK 3 β磷酸化位点大致相同。当下游的脯氨酸导向位点被磷酸化时，两个非脯氨酸导向的磷酸化位点被发现确实是GSK 3 β的基序。 ...更多信息 ar way.主要困难是对许多特定蛋白酶的不寻常抗性和从HPLC柱中回收磷酸肽非常差，这在胎儿tau中从未经历过。PHF-tau在最多21个位点被磷酸化; 10个是脯氨酸定向的，而11个是非脯氨酸定向的。在胎儿tau中磷酸化的大多数位点也在PHF-tau中磷酸化，这解释了PHF-tau和胎儿tau之间的那些免疫化学相似性。总体而言，PHF的磷酸化可以被认为是由胎儿型磷酸化加上额外的脯氨酸定向和非脯氨酸定向磷酸化组成。这些非脯氨酸导向位点中的一些对应于由cAMP依赖性蛋白激酶（PKA）磷酸化的位点。因此，PHF-tau的磷酸化可能是由多种激酶，cdk 5，GSK 3 β，可能PKA介导的。这些非脯氨酸指导的磷酸化，区分PHF-tau和胎儿tau可能是重要的PHF-tau的不寻常的特性，包括其组装无能和蛋白酶抗性。少

项目成果

Oyama F et al.: "Differential expression of β amyloid protein precursor (APP) and tau mRNA in the aged human brain:Individual variability and correlation between APP-751 and four-repeat tau." J.Neuropathol.Exp.Neurol.50. 560-578 (1991)

Oyama F 等人：“老年人大脑中 β 淀粉样蛋白前体 (APP) 和 tau mRNA 的差异表达：APP-751 和四重复 tau 之间的个体变异性和相关性 J.Neuropathol.Exp.Neurol.50。” .560-578 (1991)

Ihara Y et al.: "The regenerative process of Alzheimer's disease.Proceedings of the XIth International Congress of Neuropathology." Neuropathology. 4. 110-115 (1991)

Ihara Y 等人：“阿尔茨海默病的再生过程。第十一届国际神经病理学大会论文集。”

Mizutani T et al.: "Clinicopathologic study of dementia in Parkinson disease." Dementia. 2. 229-236 (1991)

Mizutani T 等人：“帕金森病痴呆的临床病理学研究。”

Yanagisawa K et al.: "Secretory pathway of β/A4 amyloid protein precursor in familial Alzheimer's disease with Val_<717> to Ile mutation." Neurosci Lett. 144. 43-45 (1992)

Yanagisawa K 等人：“具有 Val_<717> 至 Ile 突变的家族性阿尔茨海默病中 β/A4 淀粉样蛋白前体的分泌途径。 Neurosci Lett。”

Oyama F et al.: "β-Amyloid protein precursor and tau mRNA levels versus β-amyloid plaque and neurofibrillary tangles in the aged human brain." J Neurochem. 60. 1658-1664 (1993)

Oyama F 等人：“老年人脑中 β-淀粉样蛋白前体和 tau mRNA 水平与 β-淀粉样斑块和神经原纤维缠结的关系。”J Neurochem 60. 1658-1664 (1993)