Species-Specific Variations of A-to-I RNA Editing in Three Tegulidae Gastropods

RNA editing is a post-transcriptional modification in metazoans and plays a crucial role in environmental adaptation. To elucidate the species specificity of RNA editing in marine mollusks and advance the comprehension of their post-transcriptional modifications, we selected three Tegulidae gastropods, Rochia conus, R. maxima, and Tectus pyramis, from coral reefs in the South China Sea and performed transcriptome-wide RNA editing analysis. The results showed that adenosine-to-inosine (A-to-I) RNA editing was the most prevalent editing type among these three Tegulidae species. The number of A-to-I editing sites (per Gb) and the editing level of these sites varied significantly among species (p < 0.05). Notably, the A-to-I editing density (number of A-to-I edited sites per Gb) of R. conus clustered with that of R. maxima, consistent with their clustering in the adenosine deaminases acting on RNA (ADAR) phylogeny. Furthermore, Gene Ontology analysis revealed that the edited coding genes of R. conus, R. maxima, and T. pyramis were mainly enriched in "neuron projection membrane," "cellular response to toxic substance," and "threonine catabolic process," respectively. These results suggest that the RNA editing patterns of the family Tegulidae are species-specific and that A-to-I RNA editing density is correlated with the ADAR phylogenetic history.