Preliminary identification and analysis of differential RNA editing between higher and lower backfat thickness pigs using DNA-seq and RNA-seq data.

RNA editing is an essential post-transcriptional regulatory mechanism. However, few studies have investigated the functional RNA edits in the economic traits of livestock on a genome-wide scale. Pigs are one of the most important livestock species and their fat is the principal organ involved in the regulation of adipose deposition. Here, we used three full-sibling pairs, with each pair comprising a pig with higher backfat (BF) thickness and lower backfat thickness, to identify RNA editing events based on whole-genome and transcriptome sequencing data. A total of 60,903 non-redundant RNA editing sites with 59,472 (97.7%) A-to-G edits were detected using a revised bioinformatics pipeline. A specific sequence context with G preference was found one base downstream of the edited site, and the editing level was associated with the distribution of nucleotides across nearly sites. Moreover, the A-to-G editing sites mostly occurred in the pig-special short interspersed nuclear elements, Pre0_SS. Comparing the difference between pigs with higher BF and lower BF, we found 211 differentially edited sites (DESites). Functional enrichment analyses revealed a significant enrichment of genes containing DESites in terms of adipose deposition. The DESites located in the six adipose-related genes (SKP1, GSK3B, COL5A3, MDM4, NT5C2, and DENND2A) were selected as candidate RNA editing sites associated with adipose deposition, and thus require further evaluation. This study mined the potentially functional RNA editing sites in pig adipose tissue and indicated that RNA editing may play an important role in adipose deposition, which provides a new insight into the post-transcriptionally mediated regulation mechanism of fat development.