In this episode of the Epigenetics Podcast, we talked with Tae-Kyung Kim from POSTECH in South Korea about the discovery and characterisation of enhancer RNAs.

Dr. Kim describes joining Danny Reinberg’s lab as a graduate student, where he was trained in protein biochemistry and general transcription mechanisms. He recalls this period as a formative time, when research on transcription factors and RNA polymerase II was rapidly advancing and many findings were still novel.

Kim then moved into neurobiology through Michael Greenberg’s lab, where he first worked on a project related to L-type voltage-gated channels. He says his work shifted toward chromatin and gene regulation in neurons after learning that chromatin immunoprecipitation could be applied to neuronal systems and after the arrival of next-generation sequencing.

He explains that eRNAs were discovered in his lab through RNA-seq and ChIP-seq data from neuronal activity experiments, especially around the FOS locus. He later showed that eRNAs are transcribed from enhancers, are typically unstable, often lack splicing and polyadenylation, and have defined initiation sites, suggesting regulated transcription.

Kim says eRNAs can interact with transcription and epigenetic regulators, including factors involved in pause release and mediator complexes. He describes experiments showing that eRNA knockdown reduced ARC induction and that eRNA production depends on proper enhancer-promoter contact.

He concludes by describing newer work in his lab using spatial transcriptomics and eRNA-based reporter systems to map active neural populations, including studies related to cocaine-responsive circuits. He says his future work will focus on spatial technologies to better understand brain organization and function at molecular resolution.