Genetic robustness of let-7 miRNA sequence-structure pairs

TL;DR

This paper investigates the genetic robustness of let-7 miRNA sequence-structure pairs, introducing the IFR-spectrum as a new measure to understand how structure influences robustness against mutations.

Contribution

It presents the IFR-spectrum as a novel metric for assessing robustness of sequence-structure pairs, emphasizing the role of structure in evolution.

Findings

Structure contributes significantly to ncRNA robustness.

IFR-spectrum effectively captures robustness against multiple mutations.

Analysis reveals key features of structure-modulated evolution.

Abstract

Genetic robustness, the preservation of evolved phenotypes against genotypic mutations, is one of the central concepts in evolution. In recent years a large body of work has focused on the origins, mechanisms, and consequences of robustness in a wide range of biological systems. In particular, research on ncRNAs studied the ability of sequences to maintain folded structures against single-point mutations. In these studies, the structure is merely a reference. However, recent work revealed evidence that structure itself contributes to the genetic robustness of ncRNAs. We follow this line of thought and consider sequence-structure pairs as the unit of evolution and introduce the spectrum of inverse folding rates (IFR-spectrum) as a measurement of genetic robustness. Our analysis of the miRNA let-7 family captures key features of structure-modulated evolution and facilitates the study of robustness against multiple-point mutations.