Enhancing RNA aggregation through temperature cycling and intrinsically disordered RNA binding peptides

RNA-protein aggregates akin to membraneless organelles in modern biology offer a potential model for protocells and precursors to protocells in the chemistry of early Earth. In this project, we explore the aggregation properties of nucleic acids and their nucleotide monomers under a variety of conditions using a fluorescence dye-based assay for aggregation. The building blocks of RNA - guanosine monophosphate and adenosine monophosphate showed intrinsic concentration-dependent aggregation. Cyclic incubation between high and low temperatures, mimicking for example conditions around a hydrothermal vent, increased aggregation. This trend was enhanced when experiments were repeated with total RNA extracted from bacterial and fungal sources. RNA aggregation was further enhanced by the incorporation of peptides featuring an RNA binding sequence combined with an intrinsically disordered region. Our results show that RNA aggregation, a key first step on the pathway to protocells, can be enhanced through temperature cycling and the binding of short disordered peptides. © FASEB.