Nucleic acid nanostructures and topology

DNA is well known as the genetic material of all living organisms. However, the properties that allow it to serve so well in that role also can be exploited for chemical ends. Indeed, one of the most promising branches of nanotechnology is predicated on this genetic molecule. It is possible to make stable branched DNA molecules that can be combined through the specificity of cohesion of two ('sticky') ends with complementary overhangs to direct the construction of stick figures. Molecules whose edges consist of double- helical DNA have been constructed which show the connectivities of a cube and of a truncated octahedron. Two-dimensional arrays with programmed structural features have also been built. The topological properties of DNA have been exploited to produce specific knots and Borromean rings. In addition, DNA transitions can be used as the basis of nanomechanical devices. There is far more to DNA than a repository for genetic information!.