Expression profiling of pancreas development

Development of the pancreas from the endoderm is initiated at embryonic day 9 of mouse development and over the following days several different cell types develop from pancreas progenitor cells. A distinct phase of pancreas development, known as the secondary transition, is initiated at day 13 of development and one of the key features of this transition is a massive increase in the number of mature endocrine cells. To study gene expression in pancreas during the secondary transition we performed high-density oligonucleotide microarray experiments on dorsal pancreas tissue isolated from NMRI embryos on consecutive days from e12.5 to e16.5. Keywords: time course Dorsal pancreata were isolated from embryos at embryonic day 12.5, 13.5, 14.5, 15.5, and 16.5 and pooled litter-wise prior to total RNA extraction. From each pool, two independent labelling reactions were made, and each sample was hybridized to the entire Murine Genome U74 version 2 chip set (A, B, and C).