Figure 3.

Spatial distribution of extrinsic signals regulating EHT. The cross-section on the left provides a whole-embryo context for the tissues surrounding the dorsal aorta from which HSCs will emerge from HE via an EHT process. To the right is a list of diffusible signaling molecules known to have functions in regulating HSC production. Some of these factors are present ubiquitously in the embryo or produced from multiple sources. DA dorsal aorta, HE hemogenic endothelium, HSPC hematopoietic stem/progenitor cell, NC notochord, NT neural tube, P pronephric duct, PCV posterior cardinal vein. Figure created with BioRender.com.