You are currently viewing the abstract.View Full Text
The first artery and vein of the vertebrate embryo assemble in the trunk by migration and coalescence of angioblasts to form endothelial tubes. The gridlock (grl) mutation in zebrafish selectively perturbs assembly of the artery (the aorta). Here it is shown that grl encodes a basic helix-loop-helix (bHLH) protein belonging to the Hairy/Enhancer of the split family of bHLH proteins. The grl gene is expressed in lateral plate mesoderm before vessel formation, and thereafter in the aorta and not in the vein. These results suggest that the arterial endothelial identity is established even before the onset of blood flow and implicate the grl gene in assignment of vessel-specific cell fate.
↵* These authors contributed equally to this work.
↵† Present address: Aventis Pharma, 26 Landsdowne Street, Cambridge, MA 02139, USA.
↵‡ Present address: Jake Gittlen Cancer Research Institute, Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA.
↵§ Present address: Unit on Vertebrate Organogenesis, Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, Building 6B, 6 Center Drive, Bethesda, MD 20892, USA.
↵|| To whom correspondence should be addressed. E-mail: