R-loop editing by DNA cytosine deaminase APOBEC3B modulates the activity of oestrogen receptor enhancers - PubMed
4 days ago
- #Oestrogen Receptor
- #R-loop
- #APOBEC3B
- APOBEC3B (A3B) acts as a co-activator of the oestrogen receptor (ER) and is involved in inducing DNA double-strand breaks (DSBs) at ER-regulated enhancers.
- A3B preferentially targets transcriptionally active regulatory regions in an R-loop-dependent manner, as shown in a cell model lacking base excision repair (BER) function.
- A3B binds to and deaminates single-stranded DNA (ssDNA) within R-loops, a process facilitated by ER transactivation.
- BER-mediated processing of A3B-induced uracil bases contributes to the formation of R-loop-associated DSBs, essential for ER-regulated gene activation.
- The study highlights A3B's role in R-loop homeostasis and transcriptional regulation, with implications for understanding ER-driven genomic instability and potential therapeutic targeting of A3B.