High affinity VEGF binding and developmental expression suggest Flk-1 as a major regulator of vasculogenesis and angiogenesis.
Examination of flk-1 receptor tyrosine kinase mRNA expression by in situ hybridization analysis revealed specific association with endothelial cells at all stages of mouse development, including the blood islands in the yolk sac of day 8.5-10.5 embryos, in which the early progenitors of this lineage originate. flk-1 transcripts were abundant in proliferating endothelial cells of vascular sprouts and branching vessels of embryonic and early postnatal brain, but were drastically reduced in adult brain, where proliferation has ceased. Identification of the angiogenic mitogen, vascular endothelial growth factor (VEGF), as the high affinity ligand of Flk-1 and correlation of the temporal and spatial expression pattern of Flk-1 and VEGF suggest a major role of this ligand-receptor signaling system in vasculogenesis and angiogenesis.
Millauer
B
B
Department of Molecular Biology, Max Planck Institute for Biochemistry, Martinsried, Federal Republic of Germany.
Wizigmann-Voos
S
S
Schnürch
H
H
Martinez
R
R
Møller
N P
NP
Risau
W
W
Ullrich
A
A
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000098:blood supply / Q000196:embryology; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D016228:Endothelial Growth Factors / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000502:physiology; D015870:Gene Expression; D017403:In Situ Hybridization; D008222:Lymphokines / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009389:Neovascularization, Pathologic; D016133:Polymerase Chain Reaction; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D040262:Receptors, Vascular Endothelial Growth Factor; D016415:Sequence Alignment; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D004247:DNA; D011505:Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor