Role of Pax genes in endoderm-derived organs

Pax genes, which encode a family of transcription factors, ave essentially required for the formation of several tissues from all germ layers in the m ammalian embryo. Specifically, in organogenesis, they ave involved in trigg ering early events of cell differentiation. The differentiation of endoderm -derived endocrine pancreas is mediated through Pax4 and Pax6. In the thyro id gland, Pax8 is essential for the formation of thyroxine-producing follic ular cells, also of endodermal origin. The analysis of loss-of-function mut ants revealed a common function of Pax genes in organogenesis.