The neuronal A-to-I RNA editome of Solenopsis invicta expands conserved recoding repertoire between two ant species

A-to-I RNA editing expands proteomic diversity and may contribute to caste-specific phenotypic plasticity in eusocial insects. However, the quantity-accuracy trade-off in editing detection usually hinders comprehensive characterization of the RNA editome.

To overcome the quantity-accuracy trade-off, we first perform de novo identification of the neuronal A-to-I editome of the red imported fire ant Solenopsis invicta, and then apply an orthology-based strategy to project candidate editing sites to another ant species Acromyrmex echinatior.

We obtain nearly 3000 editing sites in S. invicta, including 91 nonsynonymous (recoding) sites enriched in neuronal functions such as synaptic transmission, ion channels, and circadian rhythms. The orthology-based strategy substantially expands the previously known recoding repertoire in the leaf-cutting ant A. echinatior, reveals many previously missed recoding sites and edited genes, and uncovers additional caste-specific recoding events between gynes and workers, highlighting conserved, potentially functional editing targets across ant evolution. Representative recoding sites are validated by Sanger sequencing.

Our work expands ant RNA editome resources and identifies conserved recoding candidates that may facilitate future studies of eusocial caste diversification, neuronal function, and phenotypic plasticity.