BioProject

During mammalian gastrulation, pluripotent epiblast stem cells migrate through the primitive streak to form the multipotent progenitors of the mesoderm and endoderm germ layers. More...

During mammalian gastrulation, pluripotent epiblast stem cells migrate through the primitive streak to form the multipotent progenitors of the mesoderm and endoderm germ layers. Msgn1 is a bHLH transcription factor and is a direct target gene of the Wnt/bcatenin signaling pathway. Msgn1 is expressed in the mesodermal compartment of the primitive streak and is necessary for the proper development of the mesoderm. Msgn1 mutants show defects in somitogenesis leading to a lack of trunk skeletal muscles, vertebra and ribs. To study the molecular and cellular function of Msgn1 in Embryonic Stem Cells (ESC), we have generated doxycycline inducible gain-of-function ESC to overexpress Msgn1 in ESC. In order to identify Msgn1 targets, we performed transcriptional profiling of Msgn1 expressing ES cells and found that upon induction of Msgn1, multiple genes in the Notch pathway were differentially expressed compared to the uninduced cells. Moreover, Whole Mount Insitu Hybridization analysis in Msgn1 null mutants revealed that these Notch pathway genes required Msgn1 for their proper expression in vivo. Our studies demonstrate that Msgn1 is a critical effector of the Wnt pathway during mammalian somitogenesis, mediating crosstalk between the Wnt and Notch pathways. Overall design: Inducible A2lox-Flag Msgn1 ES cells were differentiated to form Embryoid bodies (EBs) for 2 days. Flag-Msgn1 was induced on day 2 with doxycycline and samples were collected at three time points, 12h, 24h and 48h after addition of doxycycline. Uninduced cells were used as controls. Experiments were performed in triplicate Less...