Identification of distinct vascular mural cell populations during zebrafish embryonic development

Abstract

BackgroundMural cells are an essential perivascular cell population that associate with blood vessels and contribute to vascular stabilization and tone. In the embryonic zebrafish vasculature, pdgfrb and tagln are commonly used as markers for identifying pericytes and vascular smooth muscle cells. However, the overlapping and distinct expression patterns of these markers in tandem have not been fully described.ResultsHere, we used the Tg(pdgfrb:Gal4FF; UAS:RFP) and Tg(tagln:NLS‐EGFP) transgenic lines to identify single‐ and double‐positive perivascular cell populations on the cranial, axial, and intersegmental vessels between 1 and 5 days postfertilization. From this comparative analysis, we discovered two novel regions of tagln‐positive cell populations that have the potential to function as mural cell precursors. Specifically, we found that the hypochord—a reportedly transient structure—contributes to tagln‐positive cells along the dorsal aorta. We also identified a unique mural cell progenitor population that resides along the midline between the neural tube and notochord and contributes to intersegmental vessel mural cell coverage.ConclusionTogether, our findings highlight the variability and versatility of tracking both pdgfrb and tagln expression in mural cells of the developing zebrafish embryo and reveal unexpected embryonic cell populations that express pdgfrb and tagln.

Endothelial cell Piezo1 promotes vascular smooth muscle cell differentiation on large arteries

“…vSMC accumulation on arteries is a process that occurs across all vertebrates during the early stages of development in response to mechanical forces. In the zebrafish, this accumulation starts between 2 and 3 days post fertilization (dpf) and follows a rise in pulse pressure after the onset of blood flow 9,[12][13][14][15][16][17][18][19][20][21] . As this relationship between vSMC and pulse pressure occurs in all vertebrates, the current paradigm is that vSMC recruitment happens in response to high shear, pulsatile flow in the arterial vasculature.…”