[Analysis of the dynamics of transitions in Leptomonas collosoma spliced leader RNA and a possible role of gaps upon splicing].

In [1], the existence of two competing secondary structures at the 5'-end of Leptomonas collosoma spliced leader RNA was shown. On going from one steady-state secondary structure to the other, and vice versa, RNA passes through several states in which the chain gets tied up into nodes. If the transitions are reversible, the nodes are figurative both in the forth and back directions although the secondary structures that arise in this process are quite different, and the forth and back routs do not coincide. It is assumed that under certain conditions, the chain can get tied into the next node of series 5(2), which most likely will not get untied. This node is tightened around GG nucleotides. In this case, the migration of the gap is possible, as a result of which the chain can break. Independent experiments indicate that the RNA chain breaks just at this site upon splicing. Based on these results, a possible role of nodes in the enzymatic activity is discussed.