Glassy kinetic barriers between conformational substates in RNA

We study by means of a Monte Carlo simulation the rates of interconversion of metastable RNA secondary structures as the thermodynamic limit is approached. The sequences are random and uncorrelated and the refolding events are kinetically controlled and occur as the chain grows by sequential random incorporation of nucleotides. The scaling law connecting the size of the barriers with the length of the chain exhibits a striking similarity with the related kinetics of spin glasses and other disordered systems.