Vascular specification from diversified mesoderm culminates in endothelial convergence

Vascular specification in mouse vasculogenesis emerges from distinct pre-specified mesoderm sources via a transient Kdr+Etv2- vascular-primed state promoted by BMP signaling, persisting until E8.0–E8.5.

• Why it matters: It remains unclear how a common vascular program forms across multiple embryonic and extraembryonic developmental environments during vasculogenesis.
• What they did: The authors reconstructed mouse vasculogenesis using integrated single-cell, spatial, lineage, and perturbation analyses, then used temporal VEGF signaling perturbations to test the inferred sequence.
• The result: VEGF is downstream of vascular priming and is indispensable for vascular and primitive blood specification, while endothelial derivatives converge on a shared transcriptional state that retains origin-specific traces.