Claim: PDX1 is a transcription factor for pancreatic development; it is a protein that controls the rate of transcription of genetic information, turning on and off genes in order to make sure they are expressed in the right cell at the right time, and in the right amount.
Evidence: PDX1 (pancreatic and duodenal homeobox 1), also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster. In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The function of TFs is to regulate—turn on and off—genes in order to make sure that they are expressed in the right cell at the right time and in the right amount throughout the life of the cell and the organism. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation.