Low-error RNA sequencing techniques for detecting RNA editing by APOBECs: Circular RNAseq assay and safe-sequencing system (SSS)

Methods Enzymol. 2025:713:15-30. doi: 10.1016/bs.mie.2024.12.004. Epub 2025 Jan 10.

Abstract

Cytidine-to-Uridine (C-to-U) RNA editing is a post-transcriptional modification essential for various biological processes. APOBEC deaminases mediate C-to-U editing which play critical role in cellular function and regulation. Advances in next-generation sequencing (NGS) technologies and analytical tools have provided powerful means to assess RNA editing activities and their physiological implications. However, inherent errors in NGS workflows-including reverse transcription, PCR amplification, and sequencing-complicate the detection of actual editing events. With error rates ranging from 10-2 to 10-3 per nucleotide, these technical artifacts can obscure APOBEC-mediated editing events occurring at similar frequencies. To address these challenges, in this chapter, we describe two established and optimized RNA sequencing strategies explicitly designed to detect low-frequency RNA editing events accurately while distinguishing them from NGS-associated errors. These methods are termed "circular RNA Sequencing Assay" and "Safe-Sequencing System (SSS)" and enable the reliable identification of RNA editing events (and also somatic mutations) at or below typical error thresholds.

Keywords: ADARs; APOBEC deaminases; Circular RNA sequencing; Low error RNA sequencing techniques; RNA editing; RNA editing enzymes; Safe-RNA sequencing system.

MeSH terms

  • APOBEC Deaminases* / genetics
  • APOBEC Deaminases* / metabolism
  • High-Throughput Nucleotide Sequencing* / methods
  • Humans
  • RNA Editing*
  • RNA, Circular* / genetics
  • Sequence Analysis, RNA* / methods

Substances

  • APOBEC Deaminases
  • RNA, Circular