NFIA regulates pancreatic cell fate and adult physiology through vesicle trafficking

Intracellular trafficking is essential for proper cell signaling. In the pancreas, secretory cells rely on trafficking to regulate blood glucose and digestion. Pancreatic disorders reflect defects in function or development, evoking considerable interest in understanding the molecular genetics governing pancreatic organogenesis. Here, we show the transcription factor NFIA regulates trafficking in both the embryonic and adult pancreas, affecting both developmental cell fate decisions and adult physiology. NFIA deletion from pancreatic progenitors led to the development of more acinar cells and ducts and fewer endocrine cells, whereas ectopic NFIA promoted endocrine formation. We found that NFIA’s effects on trafficking influence endocrine/exocrine cell fate decisions through regulation of Notch. Adult NFIA-deficient mice develop diabetic phenotypes due to impaired insulin granule trafficking and defects in acinar zymogen secretion. This study shows how a single transcription factor, NFIA, thus exerts profound effects on both embryonic cell fate and adult physiology by regulating vesicle trafficking. 2 control and 2 NFIA fl/fl; Pdx1-cre samples, from pooled embryonic litters at E17.5