What defines the seeding and cross-seeding potential of amyloid particles?

什么定义了淀粉样蛋白颗粒的播种和交叉播种潜力？

• 批准号: BB/M02427X/1
• 负责人: Wei-Feng Xue
• 金额: $ 46.85万
• 依托单位: University of Kent
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM02427X%2F1
• 关键词: What; defines; seeding; cross; potential

A number of devastating human brain disorders, for example Alzheimer's disease (AD), Hungtington's diseases, diabetes type 2 and transmissible spongiform emcephalopathies (TSEs), are associated with the abnormal folding of proteins. The net result of this misfolding is the formation of large insoluble protein deposits and small toxic protein particles in a state called amyloid. The deposition of aggregated protein material in various tissues (e.g. brain, liver etc) is one of the many common characteristics shared by these diseases. Importantly, these disorders also share a similar method by which the misfolded and aggregated proteins are propagated in the disease conditions. In this process, different proteins in the cell are triggered to undergo a major change in their structure to form the highly robust amyloid state. One crucial step in amyloid formation is that the addition of preformed amyloid particles, the seeds, can greatly accelerate amyloid growth, and this phenomenon is called seeding. In some cases these seed particles are considered as infectious entities, capable of transmitting the disease to neighbouring cells, tissues, or another individual of the same or a different species, as in the case of the TSEs and possibly in other amyloid diseases such as Alzheimer's disease. The current and projected impact of these diseases on human health and welfare cannot be understated yet the fundamental question of how is the amyloid state propagated through seeding remains to be fully resolved. In some of the diseases associated with protein misfolding, more than one type of amyloid aggregate may exist where each type of aggregate is made of a protein with a different amino acid sequence. For example, in Alzheimer's disease the co-existence of various amyloid forms of the diagnostic amyloid-beta protein and at least one other different protein has been reported in patients including the presence of transmissible prion protein aggregates. Furthermore, recent reports have suggested that the onset of prion disease can be influenced and possibly enhanced by the presence of amyloid-beta deposits. This co-existence of two different amyloids in the same patient can be potentially explained by the interaction between misfolded proteins with each other, accelerating their respective conversions to the amyloid state. Therefore, the amyloid seeding and cross-seeding process is also potentially involved in the devastating synergetic effects in amyloid diseases.Our aim is to study the fundamental process of amyloid seeding by a combination of test tube-based in vitro approaches as well as cell-based in vivo approaches using the baker's yeast Saccharomyces cerevisiae as a safe and experimentally tractable model. In our project we will map the seeding potency of well-characterised amyloid seed samples, monitoring the growth of the amyloid fibrils using natural seeds or seeds formed from other amyloid proteins, so called "cross-seeding". We will then investigate how "cross-seeding" occurs in the yeast cell using a novel yeast prion-based assay. Since yeast prions are infectious but non-toxic, this system allows us to follow amyloid formation and propagation without causing cell death and therefore we can investigate the fundamental principles of cross-seeding in a living cell. Overall, our project will allow us to establish the nature and spectrum of the potential interactions between misfolded proteins and the dependence, if any, on cellular components in generating this important disease-associated amyloid forms.

许多毁灭性的人脑疾病，例如阿尔茨海默氏病（AD），亨廷顿疾病，2型糖尿病和可传播的海绵臂是（TSES）与蛋白质的异常折叠有关。这种错误折叠的结果是形成了称为淀粉样蛋白的状态下的大型不溶性蛋白沉积物和小有毒蛋白颗粒。聚集的蛋白质物质在各种组织（例如大脑，肝等）中的沉积是这些疾病共有的许多共同特征之一。重要的是，这些疾病还具有类似的方法，通过该方法在疾病条件下传播错误的蛋白质和汇总蛋白质。在此过程中，触发细胞中的不同蛋白质会经历其结构的重大变化，以形成高度健壮的淀粉样蛋白。淀粉样蛋白形成的一个关键步骤是，添加预先形成的淀粉样蛋白颗粒，种子可以极大地加速淀粉样蛋白的生长，这种现象称为播种。在某些情况下，这些种子颗粒被认为是传染性实体，能够将疾病传播到相邻的细胞，组织或其他物种的其他个体，例如TSE，以及可能在其他淀粉样蛋白（例如阿尔茨海默氏病）中。这些疾病对人类健康和福利的当前和预测影响还不能低估，但通过播种如何传播的淀粉样蛋白状态的基本问题仍然需要完全解决。在某些与蛋白质错误折叠相关的疾病中，可能存在多种类型的淀粉样蛋白聚集体，而每种骨料均由具有不同氨基酸序列的蛋白质制成。例如，在阿尔茨海默氏病中，已经报道了包括可传播prion蛋白聚集体的患者，包括诊断性淀粉样蛋白蛋白质的各种淀粉样形式的淀粉样蛋白形式和至少另一种不同的蛋白质共存。此外，最近的报道表明，淀粉样蛋白β沉积物的存在可能会影响幼虫疾病的发作，并可能增强。同一患者中两种不同的淀粉样蛋白的这种共存可以通过彼此错误折叠蛋白之间的相互作用来解释，从而加速了它们各自的转化为淀粉样蛋白。 Therefore, the amyloid seeding and cross-seeding process is also potentially involved in the devastating synergetic effects in amyloid diseases.Our aim is to study the fundamental process of amyloid seeding by a combination of test tube-based in vitro approaches as well as cell-based in vivo approaches using the baker's yeast Saccharomyces cerevisiae as a safe and experimentally tractable model.在我们的项目中，我们将使用由天然种子或由其他淀粉样蛋白形成的天然种子或种子（所谓的“交叉种子”）绘制出良好的淀粉样蛋白种子样品的播种效力，从而监测淀粉样蛋白原纤维的生长。然后，我们将使用基于酵母菌的新测定法研究酵母细胞中的“交叉种子”。由于酵母菌pr是传染性但无毒的，因此该系统使我们能够遵循淀粉样蛋白的形成和传播而不会导致细胞死亡，因此我们可以研究活细胞中杂种的基本原理。总体而言，我们的项目将使我们能够建立错误折叠蛋白与依赖性（如果有的话）之间的潜在相互作用的性质和频谱，以产生这种重要的疾病相关淀粉样蛋白形式。

项目成果

Nucleation: The Birth of a New Protein Phase.

• DOI: 10.1016/j.bpj.2015.10.011
• 发表时间: 2015-11
• 期刊: Biophysical journal
• 影响因子: 3.4
• 作者: Wei-Feng Xue

Amyloid particles facilitate surface-catalyzed cross-seeding by acting as promiscuous nanoparticles

淀粉样蛋白颗粒通过充当混杂的纳米颗粒来促进表面催化的交叉播种

• DOI: 10.1101/2020.09.01.278481
• 发表时间: 2020
• 作者: Koloteva-Levine N

Insights into the variability of nucleated amyloid polymerization by a minimalistic model of stochastic protein assembly

• DOI: 10.1063/1.4947472
• 发表时间: 2016-05-07
• 期刊: JOURNAL OF CHEMICAL PHYSICS
• 影响因子: 4.4
• 作者: Eugene, Sarah;Xue, Wei-Feng;Doumic, Marie
• 通讯作者: Doumic, Marie

Amyloid particles facilitate surface-catalyzed cross-seeding by acting as promiscuous nanoparticles.

• DOI: 10.1073/pnas.2104148118
• 发表时间: 2021-09-07
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Koloteva-Levine N;Aubrey LD;Marchante R;Purton TJ;Hiscock JR;Tuite MF;Xue WF
• 通讯作者: Xue WF