RNA polymerase II elongation factor ELL3 (ELL3)

Enhancer-binding elongation factor that specifically binds enhancers in embryonic stem cells (ES cells), marks them, and is required for their future activation during stem cell specification. Doesn't only bind to enhancer regions of active genes, but also marks the enhancers that are in a poised or dormant state in ES cells and is required for establishing proper RNA polymerase II occupancy at developmentally regulated genes at a cohesin-dependent method.

Probably required for priming developmentally regulated genes for later recruitment of the super elongation complex (SEC), for transcriptional activation during differentiation. Required for recruitment of P-TEFb within SEC during differentiation.