Reconstructing species evolutionary trees using the numerical features of microRNA

Research has revealed that some microRNAs show obvious lineage or species specificity, but others show highly conserved properties among species. Based on these properties, we aimed to reconstruct a species evolution tree using a new technique that refers to the numerical features of microRNA. First, we selected 132 microRNA numerical features that included base content, secondary structure matching state frequency, free energy features and information entropy features, and 32 species that included 22 animals, 9 plants and a representative virus group. Second, we found several significantly different numerical features among lineages or species by statistical analysis and confirmed that differences in each numerical feature were not identical. Third, we designed a comprehensive feature and confirmed that it showed obvious lineage and species specificity. Last, species trees were built using the comprehensive feature. The results showed that the reconstructed species tree was almost in keeping with the actual chronological order of species evolution. This indicated that our analysis was effective. Our research strategy offers a new route for investigating species evolution.