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Gridlock signalling pathway fashions the first embryonic artery
1Cardiovascular Research Center, Massachusetts General Hospital, Department of Medicine, Harvard Medical School, Charlestown 02129, USA.
Nature
|November 9, 2001
Summary
The study reveals how arteries and veins develop from mixed precursors in zebrafish. A gene called gridlock (grl), regulated by Notch signaling, guides these cells to become either arterial or venous.
Area of Science:
- Developmental Biology
- Vascular Biology
- Genetics
Background:
- Arteries and veins exhibit distinct morphological, functional, and molecular characteristics.
- The developmental mechanisms establishing arterial-venous differentiation during vasculogenesis remain largely unknown.
Purpose of the Study:
- To investigate the molecular pathways governing the initial arterial-venous cell fate decisions during embryonic development.
- To elucidate the role of the gridlock (grl) gene and Notch signaling in establishing vascular patterning.
Main Methods:
- Lineage tracking in zebrafish embryos to trace angioblast precursor fates.
- Gene expression analysis of arterial (ephrin-B2) and venous (EphB4 receptor) markers.
- Genetic manipulation using mutations and morpholino antisense to alter gridlock (grl) and Notch signaling (Su(H)).
Main Results:
- Angioblast precursors for arteries and veins are initially spatially intermixed.
- Gridlock (grl) expression is restricted to arterial precursors and is crucial for artery formation.
- Reduced grl or Notch signaling leads to arterial-to-venous fate conversion, evidenced by marker expression changes.
Conclusions:
- A Notch-gridlock (grl) signaling pathway dictates the arterial cell fate during early embryonic vascular development.
- This pathway appears to adjudicate the specific arterial versus venous cell fate decision from initially uncommitted precursors.
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