Enhancer RNA mediate estrogen-induced transcriptional repression by recruiting ERa and its cofactor to selective enhancers [RNA-Seq]

ABSTRACT: Estrogen receptor alpha (ERα) signaling mainly occupies on distal enhancers within genome and plays an essential role in ERα-positive breast cancer. ERα usually requires co-factors to regulate the enhancer activity. By analysis of genome-wide nascent transcript profiling in breast cancer cells, we identified a special group of eRNAs that are functionally important for estrogen-induced transcriptional repression. In addition to stabilizing promoter-enhancer looping structure, these eRNAs recruit ERα to particular enhancers of target genes, facilitate the hierarchical formation of a functional transcriptional complex, and cause gene silencing. Interestingly, we found that ERα directly binds to eRNAs and its DNA-binding domain mediates the interaction with RNA molecules. Our ChIP-seq data in MCF-7 cells indicating that ERαwas not able to bind to E2-activated enhancers, which is consistent with the DNA-binding function reported before; moreover the DBD-truncated ERα was not able to bind to E2-repressed enhancers as well, which further supports our hypothesis that eRNA from E2-repressed enhancers help to recruit ERα to specific enhancers through the interaction with DBD domain. Substitution of ERα-DDBD showed a global effect on both induction and repression of ERα target genes as examined by RNA-seq. Further, these eRNAs help with the formation of a specific ERα-centered transcriptional complex and promote the association of the histone demethylase KDM2A, which dismisses RNA polymerase II from designated enhancers and suppresses transcription of target genes. Our work demonstrated that eRNAs, as a distinctive class of cis-acting molecules besides chromatin regulatory elements, play an important role in modulating and refining locus-specific transcriptional program.

ORGANISM(S): Homo sapiens

PROVIDER: GSE135339 | GEO | 2020/06/23

REPOSITORIES: GEO