Detection of APOBEC3B-mediated RNA editing sites in T-47D cells [RNA-seq]

RNA editing is a crucial post-transcriptional process that diversifies proteomic outcomes and influences gene expression. Particularly, the APOBEC3 family has emerged as a significant player in this mechanism, with APOBEC3A (A3A) showing notable roles in immune response and stress conditions. APOBEC3B (A3B), another family member, has garnered attention for its potential role in breast cancer genomic mutations. In this study, we employ an inducible expression cell model and a novel methodology for identifying differential variants in RNA (DVRs) to map A3B-mediated RNA editing sites in a breast cancer cell model. Our findings indicate that A3B engages in selective RNA editing and targets NEAT1 and MALAT1 long non-coding RNAs. Notably, the binding of these RNAs sequesters A3B’s catalytic activity, and thereby affects A3A’s activity through a feedback loop. To sample the RNA editing sites mediated by APOBEC3B, we conducted RNA-seq and WGS, followed by joint mutation calling and log ratio test to detect differentiated variants on RNA (DVRs).