We present “Molecular NINJA”, which is based on Stojanovic's molecular spider but crawls along a ditch formed between two DNA origami motifs. Usual molecular walker walks on the surface of DNA scaffold, but it may be suffered from physical tapping by AFM probe. So we designed a DNA origami which has a ditch that the molecular NINJA can hide in and guides its route.
Stage was designed as shown in fig. 1.
This stage is assumed as two islands floated on the marsh and a bridge which links between two islands.
So the molecular robot must goes to the goal by a roundabout route or making new scaffolds.
We designed that two islands size are diverse to distinguish start from goal.
Fig. 2. Schematic image of the molecular spider.
Fig. 3. Animation of our project strategy.
Fig. 4. Structure of (a) Stage, (b) Convex DNA origami and (c) Stage + Convex DNA origami.
Our strategy of the robot contest is using a ditch.
It is named “Molecular NINJA” because walking in a ditch is like NINJA walks on water by mizugumo.
Using a ditch has a advantage. It is reported that it is possible to tightly trap a guest using well. So the walker can walks in a ditch without suffering damage from physical tapping by AFM probe.
For the molecular walking system, self-walking molecular spider is selected (Fig. 2).
The detailed method is as follows (Fig. 3).
First, Stage is combined with Convex DNA origami and the molecular spider is landed at the start position.
Second, the DNA binding start position and spider’s leg is dissociated by chain exchange process and the walker moves to first foothold.
After moving to the final step, the walker is trapped by capture strand and bring it to near goal like using ninja’s kaginawa.
Application -Molecular Pac-man-
It is expected that we can make Molecular Pac-man system by applying Molecular NINJA system.
Molecular NINJA system has a ditch, but making plural ditches in a DNA origami will become possible to move the walker programmably.
In the future, we would like to construct some systems. For example, molecular robot choose the way to the goal automatically or change the route by existence of certain DNA or RNA.