A suite of self-assembling RNA molecules, based on the tecto-RNA molecules developed by Luc Jaeger have been designed and characterized. The designs are broadly of two kinds: pairs of molecules that heterodimerise through two tertiary RNA, Mg2+-dependent loop-receptor interactions, and four way junction molecules, each containing two loops and two receptors, which assemble into one-dimensional fibres in the presence of magnesium ions. Each of these designs has been derivatised in a number of ways to enable specific and non-specific attachment of the RNA molecules to gold nanoparticles, gold nanoelectrodes or surfaces, either through specific hybridisation of and RNA tail designed into the molecule to a DNA oligonucleotide immobilized on the desired gold partner, or by substitution of phosphorothioate linkages between ribonucleotides in place of the natural phosphodiesters, to allow direct attachment to gold partners.
The molecules have been synthesized using molecular biological methods: Polymerase chain reaction, in vitro run-off transcription, and their interactions have been characterized by denaturing and native polyacrylamide gel electrophoresis, as well as by physical methods including surface plasmon resonance. The dimerising molecules have been used by other partners for the controlled assembly of gold nanoparticles both in solution and in combination with attachment to gold nanoelectrodes, where they have been used to assemble nanowires, whose construction is controlled by the Mg2+-dependent assembly of the RNA molecules. Such assembly is the first such controlled assembly of this type. In addition, the RNA fibres have also been decorated with gold nanoparticles, and have been used as a template for the electrochemical deposition of metal on a gold surface, with the intention of forming nano-interconnects.
This work has been submitted for publication and, although at the level of basic science has the potential for use in the specific creation of nano-interconnections between particles and other components with specific functionalities.