Super-Enhancers at the Nanog Locus Differentially Regulate Neighboring Pluripotency-Associated Genes

Abstract

Super-enhancers are tissue-specific cis-regulatory elements that drive expression of genes associated with cell identity and malignancy. A cardinal feature of super-enhancers is that they are transcribed to produce enhancer-derived RNAs (eRNAs). It remains unclear whether super-enhancers robustly activate genes in situ and whether their functions are attributable to eRNAs or the DNA element. CRISPR/Cas9 was used to systematically delete three discrete super-enhancers at the Nanog locus in embryonic stem cells, revealing functional differences in Nanog transcriptional regulation. One distal super-enhancer 45 kb upstream of Nanog (−45 enhancer) regulates both nearest neighbor genes, Nanog and Dppa3. Interestingly, eRNAs produced at the −45 enhancer specifically regulate Dppa3 expression by stabilizing looping of the −45 enhancer and Dppa3. Our work illustrates that genomic editing is required to determine enhancer function and points to a method to selectively target a subset of super-enhancer-regulated genes by depleting eRNAs.

Keywords

• embryonic stem cells
• transcriptional regulation
• super-enhancers
• eRNAs
• long non-coding RNAs