Cation-induced kinetic heterogeneity of the intron-exon recognition in single group II introns.

ABSTRACT: RNA is commonly believed to undergo a number of sequential folding steps before reaching its functional fold, i.e., the global minimum in the free energy landscape. However, there is accumulating evidence that several functional conformations are often in coexistence, corresponding to multiple (local) minima in the folding landscape. Here we use the 5'-exon-intron recognition duplex of a self-splicing ribozyme as a model system to study the influence of Mg(2+) and Ca(2+) on RNA tertiary structure formation. Bulk and single-molecule spectroscopy reveal that near-physiological M(2+) concentrations strongly promote interstrand association. Moreover, the presence of M(2+) leads to pronounced kinetic heterogeneity, suggesting the coexistence of multiple docked and undocked RNA conformations. He

SUBMITTER: Kowerko D 

PROVIDER: S-EPMC4371910 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature