Transgenic analysis of the CS1 and CS2 motifs. (A) Diagram of the mouse SCL locus with the constructs used for transgenic analysis shown underneath. Vertical arrows indicate previously mapped DNaseI hypersensitive sites. Colored boxes specify enhancer regions mapped previously in transgenic mice [E = endothelial, M = midbrain, (H) hindbrain/spinal cord, (E/B) endothelial/blood]. (B) β-galactosidase activity of constructs shown inA in E11.5 transgenic mouse embryos. A whole-mount view of an E11.5 embryo together with sections of fetal liver (top) and dorsal aorta (bottom) are shown for each construct. Arrowheads in sections indicate lacZ-positive hematopoietic cells. (B) Brain; (H) heart; (L) fetal liver.
