Gene activation may involve the formation of a DNA loop that connects enhancer-bound transcription factors with the transcription apparatus at the core promoter. But this process is not well understood. Here, two proteins, mediator and cohesin, are shown to connect the enhancers and core promoters of active genes in embryonic stem cells. These proteins seem to generate cell-type-specific DNA loops linked to the gene expression program of each cell.
- Michael H. Kagey
- Jamie J. Newman
- Richard A. Young
