Cell-context dependent Notch target genes

Notch signaling regulates a variety of developmental cell fates decisions in a cell-context dependent manner. Although Notch signaling directly regulates transcription via the RBP-J/CSL DNA binding protein, little is known about the genes in the respective tissues that are directly activated by Notch. To analyze how Notch signaling mediates its context dependent functions, we utilized a Tamoxifen(OHT)-inducible system (NERT) to activate Notch1 in embryonic stem cells (ESC) at different stages of mesodermal differentiation combined with global transcriptional analyses. Notch1 signaling pathway was analysed in mouse embryonic stem cells (mESCs) that were kept under self-renewal conditions enabling ectodermal, or mesodermal gene expression (ESCe or ESCm respectively), or were differentiated into mesodermal progenitors. NotchIC were induced or not induced by hydroxytamoxifen (OHT) and addititionally in some experiments the cells were treated with protein synthesis inhibitor cycloheximide (CHX) for 4 h.