Regulatory Elements Outside Established Gene Boundaries Are Required for Multilineage Differentiation of Embryonic Stem Cells.

The transcription factor Oct4 can rightfully be considered a pivotal element in maintaining pluripotency. In addition, its ability to function as a pioneer factor enables the reprogramming of somatic cells back into a pluripotent state. To better understand the regulation of the Oct4-encoding gene (), the main genetic elements that regulate its expression in different states of pluripotency ought to be identified. While some elements have been well characterized for their ability to drive expression, others have yet to be determined. In this work, we show that translocation of the gene fragment purported to span all essential -elements, including the well-known distal and proximal enhancers (DE and PE), into the locus impairs the self-renewal of mouse embryonic stem cells (ESCs) in the naïve pluripotency state, as well as their further advancement through the formative and primed pluripotency states, inducing overall differentiation failure. These results suggest that regulatory elements located outside the previously determined boundaries are critical for the proper spatiotemporal regulation of this gene during development, indicating the need for their better characterization.