Transcription factor implicated in the cell fate determination in various organs. Binds to the E-box consensus sequence 5'-CANNTG-3'. Plays a role in early and late pancreas development and differentiation. Important for determining whether cells allocated to the pancreatic buds continue towards pancreatic organogenesis or revert back to duodenal fates. May be involved in the maintenance of exocrine pancreas-specific gene expression including ELA1 and amylase. Required for the formation of pancreatic acinar and ductal cells. Plays an important role in cerebellar development. Directly regulated by FOXN4 and RORC during retinal development, FOXN4-PTF1A pathway plays a central role in directing the differentiation of retinal progenitors towards horizontal and amacrine fates. Component of the pancreas transcription factor 1 complex (PTF1) which is composed of TCF3/p75, TCF12/p64 and PTF1A/p48. TCF3 is responsible for the nuclear import of the p48/p64 complex. Interacts with TCF3 and RBPSUH/RBP-Jkappa (By similarity). In the cytoplasm loses its ability to form the PTF1 complex. Exocrine pancreas-specific. Expressed in azaserine-induced pancreatic tumors (at protein level). Expressed in AR42J cells but not in ARIP, DSL6A, or DSL6B cells. Down-regulation is associated with the change of an azaserine-induced acinar cell carcinoma to a ductal phenotype. Expressed from day 12 of gestation in pancreatic structures.