Genome Biol Evol. 2013;5(1):181-6. doi: 10.1093/gbe/evs132.
Robustness is considered a ubiquitous property of living systems at all levels of organization, and small noncoding RNA (sncRNA) is a genuine model for its study at the molecular level. In this communication, we question whether microRNA precursors (pre-miRNAs) are actually structurally robust, as previously suggested. We found that natural pre-miRNAs are not more robust than expected under an appropriate null model. On the contrary, we found that eukaryotic pre-miRNAs show a significant enrichment in conformational flexibility at the thermal equilibrium of the molecule, that is, in their plasticity. Our results further support the selection for functional diversification and evolvability in sncRNAs.
稳健性被认为是所有组织层次上生命系统的普遍特性，而小非编码 RNA (sncRNA) 是在分子水平上研究其的典型模型。在本通讯中，我们质疑 miRNA 前体 (pre-miRNA) 是否像之前所认为的那样，在结构上具有稳健性。我们发现，天然 pre-miRNA 并不比适当的零模型所预期的更稳健。相反，我们发现真核 pre-miRNA 在分子的热平衡状态下表现出显著的构象灵活性富集，即可塑性。我们的结果进一步支持了 sncRNA 中功能多样化和可进化性的选择。
