Prediction of structural homologs to functional RNAs involved in determination of life span of Paramecium tetraurelia

抄録

The MS2 gene of Paramecium tetraurelia is supposed to be intimately implicated in the programmed association between sexual reproduction and life span and in the eventual setting of its maximum life span. The transcript of this gene is presumably an mRNA-like non-coding RNA, the function of which is evolutionarily conserved in its specific secondary structure. Therefore, characterizing the secondary structure of MS2 RNA would yield important insights about the molecular mechanism for the above cellular process that is shared among all of the organisms possessing limited longevity. In this study, it was found that P. tetraurelia has a close homolog of MS2 which undergoes the same regulation of expression as with MS2. We computationally analyzed the RNA secondary structures of MS2 and the homolog and detected four types of well-ordered structures that are both significantly more ordered and thermodynamically stable than anticipated at random. Our database searches revealed that these consensus structural features are conserved from other protozoan species to mammals. These results may suggest the functional importance of the distinct RNA structures in relation to the cellular program for organismal life span.