14-P004 A mesenchymal-like Zeb1+ niche harbors dorsal radial GFAP+ stem cells in the spinal cord

nature of Hex+Cxcr4+ (H+C+) ES cell derived ADE. Global expression analysis of ES cell derived ADE lead to the identification of an H+C+ gene expression cluster that contains well know anterior endoderm markers alongside a novel set of new sequence tags. Based on multiple pairwise comparisons between the H+C+ fraction and both differentiated and undifferentiated ES cell fractions, 66 genes were selected for further analysis. Based on cytokine response and the kinetics of gene expression in differentiation, this list was reduced to 47. In vivo expression analysis of these genes during mouse development (6.0–9.0 dpc) alongside a quantitative PCR analysis of anterior restriction, has produced an early ADE signature of five genes in addition to a number of endoderm markers that are expressed in both the anterior and posterior of the embryo. Analysis of gene ontology and domain structures in these novel genes suggests this list includes proteins involved in cell signalling, and one novel transcription factor.