PDX1

Description

The PDX1 (pancreatic and duodenal homeobox 1) is a protein-coding gene located on chromosome 13.

PDX1 (pancreatic and duodenal homeobox 1), also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the PDX1 gene, which was formerly known as IPF1. The gene was originally identified in the clawed frog Xenopus laevis and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being Pdx1, there is no Pdx2 gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two Pdx genes, Pdx1 and Pdx2. In pancreatic development, Pdx1 is expressed by a population of cells in the posterior foregut region of the definitive endoderm, and Pdx1+ epithelial cells give rise to the developing pancreatic buds, and eventually, the whole of the pancreas—its exocrine, endocrine, and ductal cell populations. Pancreatic Pdx1+ cells first arise at mouse embryonic day 8.5-9.0 (E8.5-9.0), and Pdx1 expression continues until E12.0-E12.5. Homozygous Pdx1 knockout mice form pancreatic buds but fail to develop a pancreas, and transgenic mice in which tetracycline application results in death of Pdx1+ cells are almost completely apancreatic if doxycycline (tetracycline derivative) is administered throughout the pregnancy of these transgenic mice, illustrating the necessity of Pdx1+ cells in pancreatic development. Pdx1 is accepted as the earliest marker for pancreatic differentiation, with the fates of pancreatic cells controlled by downstream transcription factors.

PDX1 is also known as GSF, IDX-1, IPF1, IUF1, MODY4, PAGEN1, PDX-1, STF-1.

Associated Diseases

Comprehensive carrier screening

WES Whole Exome Sequencing

Clinical Exome Sequencing