Elucidating the regulation and function of amyloid-like assemblies

项目总结 尽管淀粉样蛋白在许多人类疾病的病因学中的作用被最好地理解为 病理性蛋白沉积、淀粉样蛋白和淀粉样蛋白组合可发挥关键功能1。调停 这些功能，有些细胞有能力调节这些结构的组装和清除2，3。 研究的愿景是描绘健康细胞进化到的生理途径和机制 调节淀粉样蛋白的形成、功能和可逆性。这些研究的动机是我们发现在 为了控制减数分裂过程中的翻译，萌芽酵母调节RNA结合蛋白Rim4的组装 转化为具有淀粉样蛋白(因此称为淀粉样蛋白)的几种生化性质的翻译抑制物2。 从这些研究中获得的知识将使我们对疾病原因的理解取得重大进展。 神经退行性疾病和及时可能带来治疗机会。 根据我们最近对Rim4清除的研究进展，我们现在认识到酵母细胞使用多个 在减数分裂II onset4处，位点磷酸化使类淀粉样蛋白Rim4突然逆转为低聚物和单体。一个 我未来五年研究计划的主要目标是了解分子机制 在这一非凡的过程中。此外，我们还将破译触发 Rim4组件的形成，我们将阐明这些结构如何调控翻译。 芽殖酵母是研究这些过程的一个强大的实验系统。我的实验室可以很容易地 快速而同步地产生并清除淀粉样蛋白Rim4的细胞群。我们有 开发了基于荧光的记者，使我们能够量化Rim4在单细胞中的组装和功能 以及基于选择的记者，实现了强大的基因筛查。我们结合使用了这些工具 通过生物化学方法，开始阐明支配这些不同寻常的 结构是由细胞和支撑其功能的分子机制构建的。 Mira奖为我提供了启动和保持独立所需的支持 研究计划。虽然我们在实现既定目标方面取得了实质性进展，但这个奖项也给了 我实验室的研究人员可以自由地探索与我们的主要关注点背道而驰的卓有成效的东西.例如，我们 发现酵母细胞利用类淀粉样蛋白Rim4阻断反转录转座子mRNA的翻译以保护 配子发育过程中的基因组完整性。通过做出这些意想不到的发现和开发新的 工具，我的实验室已经进入了一个令人兴奋的阶段，我们正在迅速获得关于细胞如何 调节、利用和处理类淀粉样组装体。每一项发现都是通往 淀粉样蛋白相关疾病的治疗，这是必要的，因为有效的预防性治疗即使有，也很少 目前都是可用的。哥伦比亚大学和陶博阿尔茨海默氏症与老龄化研究所 提供支持框架和协作机会，使之成为可能。

PROJECT SUMMARY Although amyloids are best understood for their roles in the etiology of numerous human diseases as pathological protein deposits, amyloid and amyloid-like assemblies can serve critical functions1. To mediate these functions, some cells have the ability to regulate assembly and clearance of these structures2,3. My research vision is to delineate the physiological pathways and mechanisms that healthy cells have evolved to regulate formation, function, and reversibility of amyloids. These studies are motivated by our discovery that in order to control translation during meiosis, budding yeast regulates assembly of the RNA-binding protein Rim4 into a translational repressor that has several biochemical properties of an amyloid (thus termed amyloid-like)2. Knowledge gained from these studies will lead to important advances in our understanding of the causes of neurodegenerative diseases and in time could lead to therapeutic opportunities. Based on our recent progress studying Rim4 clearance, we now appreciate that yeast cells use multi- site phosphorylation to abruptly reverse amyloid-like Rim4 into oligomers and monomers at meiosis II onset4. A major goal of my research program over the next five years is to understand the molecular mechanisms underlying this remarkable process. Additionally, we will decipher the signals and pathways that trigger the formation of Rim4 assemblies and we will elucidate how translation is regulated by these structures. Budding yeast is a powerful experimental system to study these processes. My lab can easily grow populations of cells that rapidly and synchronously produce, and then clear, amyloid-like Rim4. We have developed fluorescence-based reporters that allow us to quantify Rim4 assembly and function in single cells and selection-based reporters that enable robust genetic screens. We have used these tools, in combination with biochemical approaches, to begin to illuminate the essential factors that govern how these extraordinary structures are constructed by the cell and the molecular mechanisms underpinning their function. The MIRA award provided me with the support that I needed to launch and maintain my independent research program. While we made substantial progress towards our stated goals, this award also gave the researchers in my lab the freedom to explore fruitful departures from our main focus. For example, we discovered that yeast cells utilize amyloid-like Rim4 to block the translation of retrotransposon mRNA to protect the genomic integrity of developing gametes. By making these unexpected discoveries and by developing new tools, my lab has entered an exciting phase where we are rapidly gaining important insights into how cells regulate, utilize, and process amyloid-like assemblies. Each discovery serves as a potential lead toward a therapy for amyloid-related diseases, which are needed because few, if any, effective preventative therapies are currently available. Columbia University and the Taub Institute for Alzheimer’s and Aging Research provides the supportive framework and collaborative opportunities to make this possible.