Fig. 6.

Selective ventral spinal cord cell types derived from Dll4-expressing progenitors/precursors. A–K: Spinal cord sections from E12.5 (A–J) or E10.75 (K) Dll4-Cre; R26R-YFP embryos were stained by double-immunofluorescence using the indicated antibodies as well as weakly counterstained with nuclear DAPI. Insets show corresponding outlined regions with representative colocalized cells at a higher magnification. Note that YFP colocalizes with Cre in many cells in the p2/V2 domain. YFP colocalizes also with Lhx3, Chx10, Gata2, Sox1, Mnx1, and Isl1/2 but rarely with Ascl1, Evx1, Nkx2.2 or En1 in distinct domains of the ventral spinal cord. L: Percentages of ventral neuron marker-positive cells that are immunoreactive for YFP at E12.5 or E10.75. Each histogram represents the mean±SD for 3 different spinal cords. Note that En1⁺ cells were counted at E10.75 when these cells could be optimally labeled, and that Sox1-positive cells were counted only for those in the V2c domains but not for those in the ventricular zone. Scale bar = 100 μm.