High-bandwidth laser tweezers detection system for directly observing the transition paths taken by single proteins and nucleic acids during structural transitions

高带宽激光镊子检测系统，用于直接观察单个蛋白质和核酸在结构转变过程中所采取的转变路径

• 批准号: 438059-2013
• 负责人: Woodside, Michael
• 金额: $ 2.21万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=507234
• 关键词: bandwidth; laser; tweezers; detection; system

Biological molecules like the proteins that make up our bodies must form intricate structures to function properly. How these structures form - a process called "folding" - is an important question for understanding biological function and for addressing diseases that arise from incorrect structures. However, the microscopic details of folding are difficult to observe because they are very fast and involve very small motions. We have developed "optical tweezers" that use lasers to grab onto single protein molecules and pull them apart, allowing us to observe structural changes with atomic-scale resolution. The timescale of the motions, however, is still too fast to resolve them properly. This project will allow us to build new tweezers instrumentation with time resolution fast enough - for the first time ever - to observe the protein while in the midst of changing its structure. It will open a new window on the folding problem, allowing us to investigate the microscopic mechanisms of folding in unprecedented detail. The instrument will first be applied to molecules with simple structures (e.g. small proteins and nucleic acids) that have been studied in depth by other techniques, both experimental and computational. By comparing to previous results, we will validate the measurements and demonstrate the improvements in resolution. We will then measure molecules with more complex structures that are involved in regulating gene expression, to understanding better the effects of structural complexity on the pathways taken by the molecule during folding. Finally, we will use the instrument to study proteins that sometimes form incorrect structures, thereby causing diseases such as "mad cow" disease & Lou Gehrig's disease. By characterising the paths taken by the proteins during the structural transitions, we hope to distinguish properties that differentiate the correct paths from those leading to diseased structures.

构成我们身体的蛋白质之类的生物分子必须形成复杂的结构才能正常运行。这些结构如何形成 - 一种称为“折叠”的过程 - 是理解生物学功能和解决不正确结构引起的疾病的重要问题。但是，折叠的微观细节很难观察到，因为它们非常快，并且涉及非常小的运动。我们已经开发了使用激光抓住单蛋白分子并将它们拉开的“光学镊子”，从而使我们能够通过原子尺度分辨率观察结构变化。但是，动作的时间表仍然太快了，无法正确解决它们。该项目将使我们能够在有史以来第一次快速的时间分辨率来构建新的镊子仪器，以便在改变其结构的过程中观察蛋白质。它将打开有关折叠问题的新窗口，使我们能够以前所未有的细节研究折叠的微观机制。该仪器将首先应用于具有简单结构（例如小蛋白质和核酸）的分子，这些结构已通过实验和计算的其他技术深入研究。通过与先前的结果进行比较，我们将验证测量结果并证明分辨率的改进。然后，我们将测量具有调节基因表达的更复杂结构的分子，以更好地理解结构复杂性对分子在折叠过程中采取的途径的影响。最后，我们将使用该仪器研究有时会形成不正确结构的蛋白质，从而导致诸如“疯牛”疾病和Lou Gehrig病等疾病。通过表征结构过渡期间蛋白质所采取的路径，我们希望区分将正确的路径与导致患病结构的路径区分开的特性。