Fig. 1From: NKX6.1 transcription factor: a crucial regulator of pancreatic β cell development, identity, and proliferationSchematic representation showing the development of the pancreas from foregut endoderm into pancreatic islet. Tip and trunk domain formation and segregation during the primary transition. During the secondary transition, the formed trunk domain (green) gives rise to the endocrine progenitors and subsequently pancreatic islets, while the tip domain (purple) develops to the exocrine progenitors expressing PTF1ABack to article page