This suggests that signals from the notochord may guide angioblasts in the fashioning of the dorsal aorta.

In both mutants the dorsal aorta fails to form, while formation of the axial vein is less affected.

Scl depletion culminates most notably in failure of dorsal aorta formation, potentially revealing a role in the formation of hemogenic endothelium.

The dorsal aorta is normally just ventral to the notochord; the axial vein is just below the dorsal aorta and above the endoderm.