GATA6 defines endoderm fate by controlling chromatin accessibility during differentiation of human-induced pluripotent stem cells

In addition to driving specific gene expression profiles, transcriptional regulators are becoming increasingly recognized for their capacity to modulate chromatin structure. GATA6 is essential for the formation of definitive endoderm; however, the molecular basis defining the importance of GATA6 to endoderm commitment is poorly understood. The members of the GATA family of transcription factors have the capacity to bind and alter the accessibility of chromatin. Using pluripotent stem cells as a model of human development, we reveal that GATA6 is integral to the establishment of the endoderm enhancer network via the induction of chromatin accessibility and histone modifications. We additionally identify the chromatin-modifying complexes that interact with GATA6, defining the putative mechanisms by which GATA6 modulates chromatin architecture. The identified GATA6-dependent processes further our knowledge of the molecular mechanisms that underpin cell-fate decisions during formative development.