A comparison of Notch, Hes and Grg expression during murine embryonic and post-natal development.

Mammalian Hairy/Enhancer-of-split-like (Hes) proteins interact with transcriptional corepressors encoded by the Groucho-related genes (Grg in mice). We have examined the embryonic and postnatal expression of the Hes1 and Hes3 genes as well as all four murine Grgs in order to determine where spatial and temporal overlaps of Hes and Grg corepressors may occur. Both within and between gene families, expression was found to occur in unique but overlapping patterns during embryonic and postnatal development. Areas where the members of these gene families are coexpressed also overlap with areas where Notch signaling is thought to maintain cells in undifferentiated or "precursor" states. Our data suggest that the coordinated transcriptional control of these genes occurs during development and that precise Hes and Grg pairings may play a role in mediating the morphogenesis of CNS and epithelialized structures.