RNAs are at the center of numerous cellular phenomena and play very different roles in each. One of their roles is in particular that of organization center: the ribosome, RNA telomerase, and “Long Noncoding RNAs” are, among others, examples of RNA structures that recruit other molecules and organize biological processes. These RNAs possess structures allowing interactions with other molecules (proteins, ligands) and thus will potentialize molecular reactions.
Advances in structural biology have permitted a defi nition of the rules with regard to the folding of RNA allowing us today to better understand exactly how they fold and interact.
As opposed to DNA, RNAs are able to adopt very variable folds and therefore are able to adopt ligand-specifi c structures. Contrary to proteins, we are able to create structures composed of different “RNA” modules, each of which is able to keep its activity independent from the others.
So, when they are stable, folded RNA can be used as a tool for biological, pharmacological, and/or molecular design studies. RNA presents the peculiarity, like Meccano, of being able to fold into structural domains, which can assemble and sometimes form supramolecular objects. We can isolate, modify, or create an RNA template de novo to make use of its recognition or enzymatic functions.
From my point of view, an “RNA scaffold” is a synthetic or natural RNA whose structure, for example, allows one to optimize a reaction, to isolate a molecule, or to favor an interaction.
Like Biobricks, the tools based on RNA scaffolds are an example of the emergence of synthetic biology. Indeed, they participate in the creation and construction of biological objects and systems for useful purposes.
In this volume, we have tried to be as representative as possible of that which is done today. You will fi nd detailed here processes and techniques that differ greatly from one to another.
This book reviews recently developed techniques that use “RNA scaffolds” as molecular tools. These methods cover domains as various as molecular biology, cellular biology, nanotechnology, and structural biology.