Probing the Role of Chaperone-TPR Complexes in Tau Proteostasis

探讨分子伴侣-TPR 复合物在 Tau 蛋白质稳态中的作用

基本信息

批准号：
10029781
负责人：
Charles Scott Craik
金额：
$ 224.04万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10029781
关键词：
Affinity Agonist Alzheimer&apos s Disease Alzheimer&apos s disease patient Animals Architecture Attention Binding Binding Sites Biochemical Brain C-terminal Cells Chemicals Client Collaborations Complex Cryoelectron Microscopy Crystallography Development Disease Engineering Ensure Enzymes Equilibrium FK506 binding protein 5 Genetic Goals Heat-Shock Proteins 70 Heat-Shock Proteins 90 Individual Laboratories Learning Libraries Location MAPT gene Maps Measures Modeling Modification Molecular Molecular Chaperones Nerve Degeneration Neurodegenerative Disorders Neurofibrillary Tangles Neurons PP5 protein-serine-threonine phosphatase Pathologic Peptide Library Peptide antibodies Peptidylprolyl Isomerase Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Play Post-Translational Protein Processing Process Progressive Supranuclear Palsy Proline-Rich Domain Protein phosphatase Proteins Proteomics Quality Control Role Scanning Solubility Structure Tauopathies Tertiary Protein Structure Time Ubiquitination Work base combinatorial corticobasal degeneration design improved inhibitor/antagonist innovation new therapeutic target novel therapeutics protein aminoacid sequence protein protein interaction proteostasis recruit tau Proteins tau aggregation tau conformation tau phosphorylation tissue-factor-pathway inhibitor 2 ubiquitin-protein ligase

项目摘要

Abstract. A devastating class of untreatable, neurodegenerative disorders, which includes progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and Alzheimer’s disease (AD), are associated with accumulation of neurofibrillary tangles (NFTs) in the brain. These aggregates are primarily composed of microtubule-associated protein tau (MAPT/tau), which is heavily modified by post-translational modifications (PTMs). If we understood how neurons normally regulate tau’s PTMs, we might be able to find ways of restoring its delicate balance. The objective of this project is to understand how the molecular chaperones, heat shock protein 70 (Hsp70) and heat shock protein 90 (Hsp90), direct modifications on tau. Hsp70 and Hsp90 are known to bind key, aggregation-prone locations in tau. While these interactions improve the solubility of tau, they also recruit a number of critical PTM enzymes including: (i) the E3 ubiquitin ligase CHIP, (ii) the cis-trans prolyl isomerase FKBP51 and (iii) the protein phosphatase PP5. Specifically, each of these enzymes contains a tetratricopeptide repeat (TPR) domain, which has affinity for the conserved EEVD-CO2H motif at the C-termini of Hsp70 and Hsp90. Thus, we hypothesize that complexes between chaperones and TPR domains ultimately determines tau’s conformation and whether it is ubiquitinated or de-phosphorylated. Thanks to innovations in cryo-EM and recent breakthroughs in large-scale peptide libraries and antibody design, we are poised to use structural and chemical approaches to understand how chaperones coordinate with TPR proteins to modify tau. In preliminary studies, we have measured binding of the chaperone’s EEVD motifs to a panel of TPR domains, revealing unexpected selectivity of Hsp70 for PP5 and Hsp90 for FKBP51, as well as a key role for phosphorylation in tuning these affinities. We have also created a library of ~640,000 peptide sequences and used it to identify a potent (<10 nM) inhibitor of CHIP’s TPR domain that does not bind closely related TPRs. Finally, we have validated a structural approach to studying the Hsp70-CHIP-tau ternary complex, a project which has already uncovered a surprising, essential role for ADP. Guided by these exciting findings and fueled by a team-based approach, we propose to study how tau interacts with: (SA1) Hsp70/Hsp90-CHIP, (SA2) Hsp90-FKBP51 and (SA3) Hsp70-PP5. Through this effort, we aim to determine how molecular switches at the key protein interfaces tune the structure and modifications on tau. We anticipate that these studies could also revealing new drug targets for treating tauopathies.

摘要。上麻痹（PSP），皮质型变性（CBD）和阿尔茨海默氏病（AD）与这些骨料中的神经纤维缠结（NFT）的积累。微管相关蛋白tau（mapt/tau），通过翻译后修饰进行了大量修饰（PTMS）。它的微妙平衡。蛋白质70（HSP70）和热休克蛋白90（HSP90），HSP70和HSP90的直接修饰。为了绑定钥匙，在tau中聚集的位置。募集许多关键的PTM酶：（i）E3泛素连接酶芯片，（ii）顺式传播酶异构酶FKBP51和（iii）蛋白质磷酸盐PP5。四肽重复（TPR）结构域，该结构域与C-termini的保守EEVD-CO2H基序有亲和力 HSP70和HSP90。确定Tau的同意以及它是泛素化还是磷酸化的。 Cryo-EM和最近在大规模肽库和抗体设计中的突破，我们有索赔使用结构和化学方法了解伴侣如何与Todify Tau坐标。在初步研究中，我们已经测量了伴侣的EEVD基序与TPR域的结合，揭示了PP5的HSP70的意外选择和FKBP51的HSP90 调整亲和力时的磷酸化。用它来识别与不密切相关的TPR的CHIP TPR结构域的有效（<10 nm）抑制剂。最后，我们已经验证了一种研究HSP70-Chip-Tau三元综合体的结构方法，这是一个项目这已经发现了ADP令人惊讶的，重要的作用。通过基于团队的方法，我们建议研究Tau如何与：（SA1）HSP70/HSP90-Chip，（SA2） HSP90-FKBP51和（SA3）HSP70-PP5。关键蛋白质接口调整了tau的结构和修改。陶醉于治疗tauopathies的新药物靶标。