Expression data from Xenopus endoderm at stage 15 following four hours of Ngn3-GR overexpression

Ngn3 is a master regulator of pancreatic endocrine development. It is necessary for the creation of all endocrine cells in mice. Little is known about the genes that act downstream of the transcription factor Ngn3 in pancreas endocrine development to specify each of the endocrine lineages. As a consequence, little is known about the genes involved in early development and the specification of the beta cell. We used microarrays to identify Ngn3 downstream genes that are involved in early and ectopic beta cell development in Xenopus laevis. We overexpressed Ngn3 in the Xenopus early endoderm and analyzed the genes that are upregulated four hours after. Xenopus laevis embryos were injected with Ngn3-GR mRNA at the eight-cell stage in the two dorsal vegetal blastomeres. Embryos at stage 12 were either treated with dexamethasone (+DEX) for four hours or no DEX (-DEX). The endoderm was dissected at stage 15. We looked for genes upregulated in the +DEX samples compared to the -DEX samples.