RNA G-quadruplexes
Several years ago, we began to work on RNA G-quadruplexes, a fascinating but contentious structure because of difficulties to prove its formation in vivo.
We discovered an unusual set of G-rich motifs in the untranslated regions of several genes from the polyamine biosynthesis pathway. Polyamines are often perceived simply as polycations, but they also play important roles mediating RNA structure and function.
Using an all-encompassing set of biophysical and cellular assays, together with NMR spectroscopy, we i) confirmed the formation of many new G-quadruplexes, ii) demonstrated that they regulate polyamine levels in cells and iii) showed that their formation is affected by cellular polyamines in feedback loops (external page eLife 2018).
We believe that research in this area is important since new variants of quadruplex structures will continue to be discovered, and these structures will lead the RNA field to new mechanisms of controlling gene expression.