Proteostasis in the aging and Alzheimer's disease brain: are the ATases novel targets?

衰老和阿尔茨海默病大脑中的蛋白质稳态：ATase 是新靶点吗？

基本信息

批准号：
9189078
负责人：
Luigi Puglielli
金额：
$ 188.07万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-01 至 2021-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9189078
关键词：
Acetyl Coenzyme A Acetylation Acetyltransferase Affect Age Age-associated memory impairment Aging Alzheimer&apos s Disease Alzheimer&apos s disease model Amyotrophic Lateral Sclerosis Animal Model Area Autophagocytosis Biochemical Biochemical Reaction Biochemistry Biological Biological Assay Biomedical Research Brain Cardiovascular Diseases Cell Line Cell Nucleus Cells Cellular Structures Chronic Computer Simulation Cytoplasm Cytosol DNA Data Degenerative Disorder Dementia Disease Endoplasmic Reticulum Enzymes Functional disorder Genetic Glutamate-ammonia-ligase adenylyltransferase Grant Healthcare Huntington Disease Immune System Diseases Impaired cognition In Vitro Kidney Diseases Laboratories Lead Link Longevity Luciferases Lysine Malignant Neoplasms Medical Membrane Transport Proteins Modeling Molecular Mus Nerve Degeneration Neurons Pathologic Pathway interactions Phenotype Physiological Population Post-Translational Protein Processing Proteins Regulation Reporter Reporting Research Risk Factors Role Stream Structural Biochemistry Structure Therapeutic Transcriptional Regulation Transferase aging brain aging population base brain tissue chromatin immunoprecipitation cost disability genetic approach improved in vivo inhibitor/antagonist mouse model neuropathology novel polypeptide protein aggregate response structural biology therapeutic target

项目摘要

Project Summary Due to the increased lifespan of our population, problems linked to age-associated disabilities are becoming more important. In particular, the disability for cognitive loss and dementia combined is currently the second most expensive among medical conditions. Aging is also the most important risk factor for sporadic Alzheimer's disease (AD). Autophagy is an essential component of the cell degrading machinery. It helps dispose of large toxic protein aggregates that form within the cell. Malfunction of autophagy contributes to the progression of many chronic age-associated diseases. Studies in mouse models of aging and AD suggest that improving proteostatic functions by stimulating autophagy can be beneficial. As such, resolving age- and disease-associated proteostasis dysfunctions as well as improving normal proteostasis mechanisms is an active target for biomedical research and a key focal area for aging research. Nε-lysine acetylation is an essential post-translational modification. For more than forty years it was assumed that lysine acetylation could only occur in the cytosol and nucleus. However, in 2007, we reported the transient lysine acetylation of endoplasmic reticulum (ER) cargo proteins. Subsequent studies revealed that the ER has two acetyltransferases (ATase1 and ATase2) as well as a membrane transporter (AT-1) that translocates acetyl- CoA into the ER lumen. Here, we report that Nε-lysine acetylation in the ER lumen regulates normal proteostasis of the secretory pathway. Consistently, by targeting the ER acetylation machinery, we were able to rescue the phenotype of a mouse model of AD, but not Huntington disease or amyotrophic lateral sclerosis. These results were obtained by using a mouse model of reduced acetylation (generated in our laboratory) as well as biochemical inhibitors that target the ATases (identified in our laboratory). The general hypothesis of this research is that functional characterization of the biochemical and biological roles of ATase1 and ATase2 will help us dissect important molecular aspects of the cognitive decline that characterizes aging and AD; a corollary hypothesis is that ATase1 and ATase2 are valid targets to improve proteostatic functions of the secretory pathway during aging and AD. Specific Aim 1 will elucidate the mechanisms responsible for the transcriptional regulation of ATase1 and ATase2 during aging and AD. Specific Aim 2 will identify structural and enzymatic features (structural biochemistry) of the ATases that can be used for translational purposes. Specific Aim 3 will target the machinery down-stream of ATase1 and ATase2 to understand how they regulate the induction of autophagy and the disposal of toxic protein aggregates. Together, Aims 1-3 will dissect the biological and biochemical roles of the ATases as a function of age and AD neuropathology, and will identify new structure-specific inhibitors to improve proteostatic functions of the brain. These Aims include a combination of structural biochemistry as well as molecular and biophysical strategies. Finally, Specific Aim 4 will use newly developed mouse models and new ATase-specific inhibitors to determine therapeutic potential.

项目概要由于人口寿命的延长，与年龄相关的残疾相关的问题越来越多特别是，目前认知丧失和痴呆所导致的残疾变得越来越重要。老龄化也是散发性疾病最重要的危险因素。自噬是细胞降解机制的重要组成部分，它有助于治疗阿尔茨海默病。处理细胞内形成的大的有毒蛋白质聚集体，导致自噬功能障碍。对衰老和 AD 小鼠模型的研究表明，许多慢性与年龄相关的疾病的进展。通过刺激自噬来改善蛋白质抑制功能可能有益于解决年龄和问题。疾病相关的蛋白质稳态功能障碍以及改善正常的蛋白质稳态机制是一个 Nε-赖氨酸乙酰化是生物医学研究的活跃目标和衰老研究的重点领域。四十多年来，人们一直认为赖氨酸乙酰化可以进行重要的翻译后修饰。只发生在细胞质和细胞核中，然而，在2007年，我们报道了瞬时赖氨酸乙酰化。随后的研究表明，内质网 (ER) 货物蛋白有两种。乙酰转移酶（ATase1 和 ATase2）以及转运乙酰基的膜转运蛋白 (AT-1) CoA 进入 ER 管腔在这里，我们报告 ER 管腔中的 Nε-赖氨酸乙酰化调节正常。一致地，通过靶向内质网乙酰化机制，我们能够实现这一点。挽救 AD 小鼠模型的表型，但不能挽救亨廷顿病或肌萎缩侧索硬化症。这些结果是通过使用乙酰化减少的小鼠模型（在我们实验室生成的）获得的以及针对 ATase 的生化抑制剂（在我们的实验室中确定）。本研究旨在对 ATase1 和 ATase2 的生化和生物学作用进行功能表征将帮助我们剖析衰老和AD特征的认知衰退的重要分子方面；推论假设是 ATase1 和 ATase2 是改善蛋白质稳态功能的有效靶标具体目标 1 将阐明衰老和 AD 期间的分泌途径。具体目标 2 将确定衰老和 AD 过程中 ATase1 和 ATase2 的转录调控。以及可用于翻译目的的 ATase 的酶学特征（结构生物化学）。具体目标 3 将针对 ATase1 和 ATase2 下游的机制，以了解它们如何调节目标 1-3 将一起剖析自噬的诱导和有毒蛋白质聚集体的处理。 ATase 的生物学和生化作用作为年龄和 AD 神经病理学的函数，并将确定新的结构特异性抑制剂可改善大脑的蛋白质抑制功能。最后，具体目标 4。将使用新开发的小鼠模型和新的 ATase 特异性抑制剂来确定治疗潜力。