Institute for Quantum Life Science, National Institute for Quantum and Radiological Science and Technology, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan.
National Institute for Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan.
J Am Chem Soc. 2020 Apr 22;142(16):7542-7554. doi: 10.1021/jacs.0c01191. Epub 2020 Apr 14.
The rotation of an object cannot be fully tracked without understanding a set of three angles, namely, roll, pitch, and yaw. Tracking these angles as a three-degrees-of-freedom (3-DoF) rotation is a fundamental measurement, facilitating, for example, attitude control of a ship, image stabilization to reduce camera shake, and self-driving cars. Until now, however, there has been no method to track 3-DoF rotation to measure nanometer-scale dynamics in biomolecules and live cells. Here we show that 3-DoF rotation of biomolecules can be visualized via nitrogen-vacancy centers in a fluorescent nanodiamond using a tomographic vector magnetometry technique. We demonstrate application of the method to three different types of biological systems. First, we tracked the rotation of a single molecule of the motor protein F1-ATPase by attaching a nanodiamond to the γ-subunit. We visualized the 3-step rotation of the motor in 3D space and, moreover, a delay of ATP binding or ADP release step in the catalytic reaction. Second, we attached a nanodiamond to a membrane protein in live cells to report on cellular membrane dynamics, showing that 3D rotational motion of the membrane protein correlates with intracellular cytoskeletal density. Last, we used the method to track nonrandom motions in the intestine of . Collectively, our findings show that the method can record nanoscale 3-DoF rotation in vitro, in cells, and even in vivo. 3-DoF rotation tracking introduces a new perspective on microscopic biological samples, revealing in greater detail the functional mechanisms due to nanoscale dynamics in molecules and cells.
如果不了解一组三个角度，即滚动、俯仰和偏航，就无法全面跟踪物体的旋转。跟踪这些角度作为三自由度（3-DoF）旋转是一种基本测量方法，例如，有助于船舶的姿态控制、图像稳定以减少相机抖动以及自动驾驶汽车。然而，到目前为止，还没有方法可以跟踪 3-DoF 旋转来测量生物分子和活细胞中的纳米级动力学。在这里，我们展示了通过荧光纳米金刚石中的氮空位中心，可以使用层析向量磁强计技术可视化生物分子的 3-DoF 旋转。我们演示了该方法在三种不同类型的生物系统中的应用。首先，我们通过将纳米金刚石附着到γ亚基上来跟踪马达蛋白 F1-ATPase 的单个分子的旋转。我们在 3D 空间中可视化了马达的 3 步旋转，并且，在催化反应中，ATP 结合或 ADP 释放步骤存在延迟。其次，我们将纳米金刚石附着在活细胞中的膜蛋白上，以报告细胞膜动力学，表明膜蛋白的 3D 旋转运动与细胞内细胞骨架密度相关。最后，我们使用该方法跟踪肠道中的非随机运动。总的来说，我们的研究结果表明，该方法可以在体外、细胞内甚至体内记录纳米级 3-DoF 旋转。3-DoF 旋转跟踪为微观生物样本带来了新的视角，更详细地揭示了由于分子和细胞中的纳米级动力学而导致的功能机制。
