Research article
Binding of ATP to vascular endothelial growth factor isoform VEGF-A165 is essential for inducing proliferation of human umbilical vein endothelial cells
1 Institut für Pharmazeutische und Medizinische Chemie, Hittorfstraße 58-62, 48149 Münster, Germany
2 Integrierte Funktionelle Genomik, Interdisziplinäres Zentrum für Klinische Forschung, Röntgenstraße 21, 48149 Münster, Germany
BMC Biochemistry 2011, 12:28 doi:10.1186/1471-2091-12-28
Published: 27 May 2011Abstract
Background
ATP binding is essential for the bioactivity of several growth factors including nerve growth factor, fibroblast growth factor-2 and brain-derived neurotrophic factor. Vascular endothelial growth factor isoform 165 (VEGF-A165) induces the proliferation of human umbilical vein endothelial cells, however a dependence on ATP-binding is currently unknown. The aim of the present study was to determine if ATP binding is essential for the bioactivity of VEGF-A165.
Results
We found evidence that ATP binding toVEGF-A165 induced a conformational change in the secondary structure of the growth factor. This binding appears to be significant at the biological level, as we found evidence that nanomolar levels of ATP (4-8 nm) are required for the VEGF-A165-induced proliferation of human umbilical vein endothelial cells. At these levels, purinergic signaling by ATP via P2 receptors can be excluded. Addition of alkaline phosphate to cell culture lowered the ATP concentration in the cell culture medium to 1.8 nM and inhibited cell proliferation.
Conclusions
We propose that proliferation of endothelial cells is induced by a VEGF-A165-ATP complex, rather than VEGF-A165 alone.



