Describing the structural robustness landscape of bacterial small RNAs

BMC Evolutionary Biology

Mario A Fares¹  Guillermo Rodrigo² 

[1] Institute of Systems and Synthetic Biology, Genopole, Universit d vry Val d Essonne, CNRS, vry Paris, France;Instituto de Biologa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Cientficas, Universidad Politcnica de Valencia, Valencia, Spain

关键词: Evolution;    Evolvability;    Plasticity;    RNA structure;    Robustness;    Small RNA;    Thermodynamics;   

DOI  :  10.1186/1471-2148-12-52

学科分类：生物科学（综合）

来源: BioMed Central

【 摘 要 】

The potential role of RNA molecules as gene expression regulators has led to a new perspective on the intracellular control and genome organization. Because secondary structures are crucial for their regulatory role, we sought to investigate their robustness to mutations and environmental changes. Here, we dissected the structural robustness landscape of the small non-coding RNAs (sncRNAs) encoded in the genome of the bacterium Escherichia coli. We found that bacterial sncRNAs are not significantly robust to both mutational and environmental perturbations when compared against artificial, unbiased sequences. However, we found that, on average, bacterial sncRNAs tend to be significantly plastic, and that mutational and environmental robustness strongly correlate. We further found that, on average, epistasis in bacterial sncRNAs is significantly antagonistic, and positively correlates with plasticity. Moreover, the evolution of robustness is likely dependent upon the environmental stability of the cell, with more fluctuating environments leading to the emergence and fixation of more robust molecules. Mutational robustness also appears to be correlated with structural functionality and complexity. Our study provides a deep characterization of the structural robustness landscape of bacterial sncRNAs, suggesting that evolvability could be evolved as a consequence of selection for more plastic molecules. It also supports that environmental fluctuations could promote mutational robustness. As a result, plasticity emerges to link robustness, functionality and evolvability.

【 授权许可】

CC BY