DNA-based force sensor with colorimetric detection | Molecular Force Balance

具有比色检测功能的基于 DNA 的力传感器 |

• 批准号: 183545761
• 负责人: Professor Dr. Tim Liedl
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/183545761?language=en
• 关键词: DNA; based; force; sensor; colorimetric

The conformational changes that many macromolecules undergo inside living cells are crucial for their biological functions. During such motions, the molecules exert and experience stretching and com-pressing forces. We propose new concepts for the measurements of forces on the piconewton scale using molecular force sensors. These sensors overcome the limitations of available force spectrosco-py techniques that require an invasive connection of the molecules with macroscopic devices such as beads or tips via long linkers. For this purpose, the powerful concepts of DNA Origami and DNA Tensegrity will be combined with established and novel single-molecule fluorescence techniques. The endeavored nanoscopic force sensors will employ the entropic force behavior of single-stranded DNA (ssDNA). The sensors will be composed of rigid DNA origami elements, which can be translocated with respect to each other. The degree of translocation will be detected optically. Therefore, photostable fluorophores and their corresponding quenchers will be attached to the DNA origami structure at designated positions. We propose concepts for nanoscopic tilting balances and spring balances. The former will enable us to measure ligand interactions in comparative assays, the latter will provide an analog readout mechanism of the sensed force: In analogy to the function of a sliding caliper, changes in distance between fluorophores of varying colors and their quenchers will lead to chromatic changes in the detected fluorescence spectrum allowing non-invasive readout of the force sensor’s state. For the future, we envision non-invasive force measurements in living cells and materials as well as new approaches to sense molecular interactions.

许多大分子在活细胞内经历的构象变化对其生物功能至关重要。在这样的运动中，分子施加并经历拉伸力和压缩力。我们提出了新的概念，使用分子力传感器的测量力的皮牛顿尺度。这些传感器克服了现有的力谱技术的局限性，该技术需要通过长连接器将分子与宏观装置（例如珠或尖端）进行侵入性连接。为此，DNA折纸和DNA张拉整体的强大概念将与已建立的和新的单分子荧光技术相结合。这种纳米尺度的力传感器将利用单链DNA（ssDNA）的熵力行为。传感器将由刚性DNA折纸元件组成，这些元件可以相对于彼此移位。易位的程度将被光学检测。因此，光稳定荧光团及其相应的猝灭剂将在指定位置连接到DNA折纸结构。我们提出了纳米倾斜平衡和弹簧平衡的概念。前者将使我们能够在比较测定中测量配体相互作用，后者将提供感测力的模拟读出机制：类似于滑动卡尺的功能，不同颜色的荧光团及其猝灭剂之间的距离变化将导致检测到的荧光光谱的颜色变化，从而允许力传感器状态的非侵入性读出。对于未来，我们设想在活细胞和材料中进行非侵入性力测量，以及检测分子相互作用的新方法。