Targeting Rab6-km23-1-mediated compartmentalized trafficking as a novel therapeutic approach to Alzheimers Disease

靶向 Rab6-km23-1 介导的区室化运输作为阿尔茨海默病的新型治疗方法

• 批准号: 9756263
• 负责人: Lance Allen Liotta
• 金额: $ 19.14万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9756263
• 关键词: Age; Alzheimer' s Disease; Alzheimer' s disease model; Amyloid; Amyloid beta-Protein Precursor; Animal Model; Area; Binding; Brain; C-terminal; Carrier Proteins; Cell model; Cells; Clinical Trials; Complex; Computer Simulation; DNA Sequence Alteration; Dendrites; Down Syndrome; Drug Targeting; Dynein ATPase; Endosomes; Engineering; Enzymes; Event; Failure; Family; Functional disorder; Golgi Apparatus; Growth; Hippocampus (Brain); Hot Spot; Human; Individual; Lead; Light; Location; MAP Kinase Gene; Mediating; Mediator of activation protein; Modeling; Motor; Mus; Mutation; Nerve; Neurites; Neurons; Organelles; Outcome; Paint; Pathogenesis; Pathology; Pathway interactions; Patients; Peptides; Play; Presenile Alzheimer Dementia; Prevention strategy; Process; Production; Protein Family; Protein Fragment; Protein Region; Proteins; Proteolysis; Recycling; Regulation; Rodent; Role; Route; Senile Plaques; Signal Transduction; Site; Sorting - Cell Movement; Structural Models; Surface; Synapses; Technology; Testing; Therapeutic; Therapeutic Agents; Transport Vesicles; Vesicle; Vesicle Transport Pathway; alpha secretase; amyloid peptide; amyloid precursor protein processing; axonopathy; base; beta secretase; beta-site APP cleaving enzyme 1; design; disease phenotype; familial Alzheimer disease; human model; induced pluripotent stem cell; inhibitor/antagonist; link protein; member; mutant; neuron loss; neuronal cell body; next generation; novel; novel strategies; novel therapeutic intervention; novel therapeutics; peptide drug; prevent; protein complex; protein protein interaction; protein transport; rab GTP-Binding Proteins; retrograde transport; spatiotemporal; synthetic peptide; targeted treatment; therapeutic target; trafficking

Summary The amyloid hypothesis as the cause for Alzheimer's Disease (AD) has recently come under fire due to the failure of so many clinical trials for amyloid peptide (Aß)-targeting therapies. However, it may be that amyloid precursor protein (APP) itself, or the C-terminal fragment-ß (CTFß) produced by ß-secretase (BACE1) cleavage, is the actual culprit in AD, having a more direct role in AD than previously thought. In the current proposal, we will study a novel approach to reducing early-stage AD by targeting the protein-protein interaction of a complex (km23-1–Rab6) that we propose controls the trafficking of APP and the rate-limiting enzyme (BACE1) in APP processing. More specifically, we will test the novel hypothesis that APP and BACE1 are transported in km23-1–Rab6 vesicles to the Golgi, where CTFß is produced to play a role in neurite outgrowth and dendritic branching. We hypothesize, further, that APP or CTFß accumulation here in AD causes exuberant and aberrant hippocampal axodentritic sprouting, eventually leading to diminish dendritic arbor complexity and breakage of neuronal branches. We will examine the km23-1–Rab6-mediated transport of APP and BACE1 to the Golgi, as well as the effects of the resulting APP fragments on dendritic branching. The results will provide a stronger basis for targeting the physical association of APP and BACE1 at Golgi sites, to reduce BACE1 activity and the subsequent production of APP intermediates. Α greater understanding of the mechanisms underlying km23-1–Rab6 regulation of APP and BACE1 interactions at the Golgi to control dendritic arborization should facilitate targeting this key trafficking event to reduce early AD-associated causal events. Our structural modeling of the km23-1–Rab6 complex revealed “hot spots” for the precise sites of protein- protein interaction. In Aim 1, we will examine the effects of site-specific mutants of the proteins on the spatiotemporal regulation of km23-1–Rab6 complexes, as well as on APP/BACE1 association and compartment location. The focus will be on APP and BACE1 association at soma Golgi, as well as at Golgi outposts (GOs) in developing dendrites, in order to better understand the mechanisms underlying APP trafficking, processing, and signaling at these specific regions. In Aims 2 and 3, we will us in silico modeling and apply a novel Protein Painting technology to reveal the unique interface by which km23-1 interacts with Rab6 in regulating APP trafficking and processing. The precise interaction region will be used to design corresponding peptide inhibitors to be tested for inhibitory effects on km23-1–Rab6 complex formation, APP processing, and AD-associated pathologies. While the majority of previous studies have used rodent familial AD (FAD) models, here we will apply human models that recapitulate sporadic AD (sAD) to test our novel km23-1–Rab6 inhibitors. The use of the hidden contact regions between these critical interacting proteins as drug targets will lead to paradigm-shifting therapies, overcoming the limitations with past therapeutic strategies. The novel therapeutic agents for AD developed as a result of the proposed studies will be among critical members of the next generation of AD-targeted therapeutics.

概括 淀粉样蛋白假说是阿尔茨海默病 (AD) 的病因，最近由于以下原因而受到批评： 淀粉样肽 (Aß) 靶向疗法的许多临床试验都失败了。然而，淀粉样蛋白可能是 前体蛋白 (APP) 本身，或由 ß-分泌酶 (BACE1) 产生的 C 末端片段-ß (CTFß) 乳沟是 AD 的真正罪魁祸首，它在 AD 中的作用比以前想象的更直接。在当前 提案中，我们将研究一种通过靶向蛋白质-蛋白质相互作用来减少早期 AD 的新方法 我们提出的复合物 (km23-1–Rab6) 控制 APP 和限速酶的运输 (BACE1) 在 APP 处理中。更具体地说，我们将测试 APP 和 BACE1 的新假设 在 km23-1–Rab6 囊泡中运输到高尔基体，在那里产生 CTFß 在神经突生长中发挥作用 和树突状分支。我们进一步假设 APP 或 CTFß 在 AD 中的积累导致 旺盛且异常的海马轴突发芽，最终导致树突乔木减少 神经元分支的复杂性和断裂。我们将检查 km23-1–Rab6 介导的 APP 运输 和 BACE1 到高尔基体，以及由此产生的 APP 片段对树突分支的影响。这 结果将为靶向 APP 和 BACE1 在高尔基体位点的物理关联提供更强有力的基础， 降低 BACE1 活性和随后 APP 中间体的产生。更深入地了解 km23-1–Rab6 调节高尔基体 APP 和 BACE1 相互作用的潜在机制 树突状树枝化应该有助于针对这一关键的贩运事件，以减少早期 AD 相关的因果关系 事件。 我们对 km23-1-Rab6 复合物的结构模型揭示了蛋白质精确位点的“热点”- 蛋白质相互作用。在目标 1 中，我们将研究蛋白质位点特异性突变体对 km23-1–Rab6 复合物的时空调节，以及 APP/BACE1 关联和 车厢位置。重点将放在高尔基体以及高尔基体的 APP 和 BACE1 关联上 发育树突的前哨站（GO），以便更好地理解 APP 的底层机制 这些特定区域的贩运、加工和信号传输。在目标 2 和 3 中，我们将进行计算机建模 并应用新颖的蛋白质绘画技术来揭示 km23-1 与 Rab6 监管 APP 贩运和处理。精确的交互区域将用于设计 待测试相应肽抑制剂对 km23-1–Rab6 复合物形成的抑制作用，APP 处理和 AD 相关病理。虽然之前的大多数研究都使用啮齿类动物家族 AD (FAD) 模型，在这里我们将应用重现零星 AD (sAD) 的人体模型来测试我们的小说 km23-1–Rab6 抑制剂。利用这些关键相互作用蛋白质之间的隐藏接触区域作为 药物靶点将导致治疗范式的转变，克服过去治疗策略的局限性。 根据拟议研究开发的新型 AD 治疗药物将是关键药物之一 下一代 AD 靶向疗法的成员。