Dynamic expression patterns of the pudgy/spondylocostal dysostosis gene Dll3 in the developing nervous system

Defects in the Notch pathway ligand Dll3 have been identified in the mouse pudgy (Dll3(pu)) and human spondylocostal dysostosis (SD, MIM 277300) mutat ions. Although these mutations are primarily associated with segmental defe cts in the axial skeleton and semitic patterning, they also exhibit cranial neurological defects. Therefore we have looked at the expression of Dll3 i n the developing mouse nervous system. The expression of Notch ligands and receptors shares common features at 10.75 dpc in the rhombic lips and dorsa l hindbrain. Temporal analysis of Dll3 expression from 9.0 to 11.0 dpc reve als that it is strongly expressed in laminar columns linked with regions of neuronal differentiation and hindbrain segmentation. Transverse sections s how that Dll3 is expressed in territories where commissural neurons are for med. We have also looked at neuronal patterning in the mid-hindbrain region in Dll3(pu) mutants. (C) 2001 Elsevier Science Ireland Ltd. All rights res erved.