Molecular cloning of Quek 1 and 2, two quail vascular endothelial growth factor (VEGF) receptor-like molecules.
We have previously reported the cloning of two partial cDNAs corresponding to two quail (Coturnix coturnix japonica) receptor tyrosine kinases (RTKs), named Quek 1 and Quek 2, and their expression in endothelial cells of the early avian embryo. We here report the cloning of the full-size cDNAs for both molecules. Sequence comparison shows that Quek 1 and 2 share an overall amino acid (aa) identity of 49%. They both comprise seven extracellular immunoglobulin-like (Ig-like) domains, a single transmembrane domain, and an intracellular kinase domain split into two by a 70 aa insertion. These structural characteristics are shared by the members of the recently discovered VEGF receptor (VEGFR) family. We have compared the sequences of Quek 1 and 2 to the other VEGFRs. At the aa level, Quek 1 is most closely related to KDR/flk-1 (VEGFR 2) (aa identity of 69% and 71%, respectively). Quek 2 shows a similar degree of aa identity to fit-4 (VEGFR 3). Quek 1 and 2 display a lower homology to fit-1 (VEGFR 1) (about 45% aa identity). These data suggest that Quek 1 and 2 are the avian homologues of VEGFRs 2 and 3, respectively.
Eichmann
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A
Institut d'Embryologie Cellulaire et Moléculaire du Centre National de la Recherche Scientifique et du Collège de France, Nogent-sur-Marne, France.
Marcelle
C
C
Bréant
C
C
Le Douarin
N M
NM
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D003370:Coturnix / Q000235:genetics; D016228:Endothelial Growth Factors / Q000235:genetics*; D008222:Lymphokines / Q000235:genetics*; D008969:Molecular Sequence Data; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D015183:Restriction Mapping; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D020794:Receptor Protein-Tyrosine Kinases