Albany 2013: Book of Abstracts
June 11-15 2013
©Adenine Press (2012)
Vascular Endothelial Growth Factor Receptor-2 (VEGFR2): Structure and Functional relationship
Vascular endothelial growth factor, VEGF, is expressed in the vicinity of sprouting vessels, and its receptor (VEGF-R2/Flk-1/kdr) on the angioblasts and new vessels, and both are required for vasculogenesis and angiogenesis. VEGFR2, also called as KDR or Flk-1, is identified as an early marker for endothelial cell progenitors, whose expression is restricted to endothelial cells in vivo. VEGFR2 consists of extracellular (7-Ig- like sub-domains), transmembrane and cytoplasmic domains. In order to understand the structure-functional relationship and signal transduction process of VEGFR2, we have examined their aminoacid sequences from a wide range of species including mammals, birds, Zebrafish and also computed the phylogenetic tree, secondary and domain structures. Phylogeny constructed using Maximum Parsimony tree software MEGA-5 version suggested an interesting sequence similarity between Zebrafish and Gallus, closeness between human, rat, horse and pig. Strong homology in aminoacids sequences were observed between the species human, Macaca mulatta, gorilla etc; and small variations in Zebrafish and zebrafinch. The Arg and Asp residues which are involved in forming salt bridges are evolutionarily conserved from Zebrafish to human in D7 domain of VEGFR2, indicating their functional importance in VEGFR activity. Aminoacids tyrosine in the extracellular loops and cysteines involved in disulphide bridges of VEGFR2 are highly conserved suggesting their importance during ligand binding, the details of which will be discussed.
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Jhansi Rani Nathan
Department of Genetics