Background of Project
There were many previous studies related to the spontaneous activities of biomolecules about Kinesin, which is a class of motor proteins, and walking DNA robots. But genuine nano-scale DNA motors which rotate at the stable speed were not yet created. In our project, we are aiming at creating the DNA screw system to achieve this goal. The rotation system is used to create the complex motion with any devices, such as drills, screws and clocks. Therefore we have thought that the nano-scale rotation system enables us to extend the future of DNA engineering. The DNA screw has many strong points. DNA screw is able to embed in any other DNA structures and to be assembled into more complex structures easily, because we can take engineering approaches to make DNA structures. And, the size of the structure can be easily scaled. In addition, DNA is a stable material than protein and can be used in various environments (ex. Temperature, pH and salt-density).
Vision for the future
One of our project’s applications is a suspension rod. Let’s imagine a pointer used in class lectures. The rod contains many cylinders and can extend and shrink by changing a relative distance of each cylinder. Inner cylinder corresponds to the DNA cylinder and outer one does to the DNA ring in our project. In addition, how the rod stretch can be controlled by ordering DNA strands. For example, the rod, which has zigzag-placed strands in parallel to the cylinder's axis, can shrink and suspend spontaneously.
By using suspending movement, our DNA screw can measure kinetic properties. In detail, the DNA screw has FRET and emits fluorescence when the relative distance between the ring and cylinder changes in preparation. Then, the DNA screw is attached to an object such as a protein. The kinetic force is detectable by observing FRET's emission. Compared to AFM, this method can observe one protein's elastic force.
Furthermore, this DNA suspension rod can provide a dynamical creating methodology for large micro-scale structures from nano-scale objects. We assume that tensegrity can be used to obtain these objects. Our DNA cylinders can function as cables and rod-shape structures such as carbon nanotube can work as rods. This method contains three steps. First, combining DNA cylinders and nano rods. Second, starting DNA spiders' movements and reaching a maximum-strength state. Third, cutting connections between DNA cylinders and nano rods and discomposing a large tensegrity structure.