RT Journal Article
SR Electronic
T1 The necessary emergence of structural complexity in self-replicating RNA populations
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 218990
DO 10.1101/218990
A1 Carlos G. Oliver
A1 Vladimir Reinharz
A1 Jérôme Waldispühl
YR 2017
UL http://biorxiv.org/content/early/2017/11/15/218990.abstract
AB The RNA world hypothesis relies on the ability of ribonucleic acids to replicate and spontaneously acquire complex structures capable of supporting essential biological functions. Multiple sophisticated evolutionary models have been proposed, but they often assume specific conditions. In this work we explore a simple and parsimonious scenario describing the emergence of complex molecular structures at the early stages of life. We show that at specific GC-content regimes, an undirected replication model is sufficient to explain the apparition of multi-branched RNA secondary structures – a structural signature of many essential ribozymes. We ran a large scale computational study to map energetically stable structures on complete mutational networks of 50-nucleotide-long RNA sequences. Our results reveal regions of the sequence landscape enriched with multi-branched structures bearing strong similarities to those observed in databases. A random replication mechanism preserving a 50% GC-content suffices to explain a natural drift of RNA populations toward complex stable structures.