Poly(A)-specific RNase (PARN) generates and regulates miR-125a-5p 3’-isoforms, displaying an altered expression in breast cancer

MicroRNAs (miRNAs) are small non-coding RNAs crucial for post-transcriptional gene regulation, processed from primary miRNA transcripts by Drosha and Dicer. 1 Latest advancements in Next Generation Sequencing highlighted the existence of miRNA isoforms (isomiRs) resulting from alternative processing, RNA editing, or post-transcriptional modifications. 1 IsomiRs can have distinct target preferences and diagnostic value in diseases like cancer. 1 Exonucleases are enzymes cleaving RNA or DNA ends, playing a vital role in miRNA regulation. 2 They control miRNA stability and biogenesis. 2