Spontaneous rearrangements in RNA sequences.

The ability of RNAs to spontaneously rearrange their sequences under physiological conditions is demonstrated using the molecular colony technique, which allows single RNA molecules to be detected provided that they are amplifiable by the replicase of bacteriophage Qbeta. The rearrangements are Mg2+-dependent, sequence-non-specific, and occur both in trans and in cis at a rate of 10(-9) h(-1) per site. The results suggest that the mechanism of spontaneous RNA rearrangements differs from the transesterification reactions earlier observed in the presence of Qbeta replicase, and have a number of biologically important implications.