Evidence for transcriptome-wide RNA editing among Sus scrofa PRE-1 SINE elements.

Area of Science:

• Molecular Biology
• Genomics
• Evolutionary Biology

Background:

• RNA editing is a post-transcriptional modification process.
• Adenosine deaminase acting on RNA (ADAR) proteins catalyze adenosine to inosine (A-to-I) editing.
• ADAR-mediated RNA editing is known to enhance genetic variation in primates.

Purpose of the Study:

• To investigate the potential for RNA editing in the pig transcriptome.
• To determine if ADAR-mediated RNA editing occurs in pigs.
• To assess the extent and characteristics of RNA editing in pigs.

Main Methods:

• Comparative analysis of DNA and RNA sequencing data from pig tissues.
• Identification and quantification of DNA-RNA mismatches.
• Bioinformatic analysis to identify canonical ADAR editing events (A-to-G mismatches).

Main Results:

• Over 8500 DNA-RNA mismatches were identified across three pig tissues.
• 75% of mismatches were A-to-G, indicative of ADAR editing.
• 94% of mismatches in repetitive regions were A-to-G, with many in the PRE-1 retrotransposon; coding region editing was also observed.

Conclusions:

• Pervasive RNA editing by ADAR occurs in pigs, extending beyond primates.
• ADAR-mediated RNA editing significantly enhances genetic variation in the pig transcriptome.
• This finding highlights the evolutionary importance of RNA editing in non-primate species.