Compact Self-Repairing DNA Lattices

Self-repair is essential to all living systems, providing the ability to remain functional in spite of gradual damage. In the context of self-assembly of self-repairing synthetic biomolecular systems, recently Winfree developed a method for transforming a set of DNA tiles into its selfhealing counterpart at the cost of increasing the lattice area by a factor of 25. The overall focus of this paper, however, is to develop compact designs for self-repairing tiling assemblies with reasonable constraints on crystal growth. Specifically, we use a special class of DNA tiling designs called reversible tiling which when carefully designed can provide inherent self-repairing capabilities to patterned DNA lattices. We further note that we can transform any irreversible computational DNA tile set to its reversible counterpart and hence improve the self-repairability of the computational lattice. But doing the transform with an optimal number of tiles, is still an open question. However, for every DNA tile encoding some computation, irrespective of its type, we can modify its design such that it can force only forward reassembly and hence improve the self-repairability of the resultant lattice.