Figure 2.

Developmental fate map of vascular smooth muscle. The different colors represent the different embryonic origins for smooth muscle cells (SMCs), as indicated in the figure. Aortic SMCs originate from 3 distinct developmental lineages. The secondary heart field (red) contributes to SMCs of the basal aortic root, the neural crest (blue) gives rise to SMCs of the ascending aorta and aortic arch, the paraxial/somitic mesoderm (yellow) contributes to SMCs of the descending aorta. The lineage boundaries depicted are shown to approximation and may change with aging.