Neuropilin-1-VEGFR-2 complexing requires the PDZ-binding domain of neuropilin-1.
Vascular endothelial growth factor (VEGF) acts as a hierarchically high switch of the angiogenic cascade by interacting with its high affinity VEGF receptors and with neuropilin co-receptors. VEGF(165) binds to both Neuropilin-1 (NP-1) and VEGFR-2, and it is believed that ligand binding forms an extracellular bridge between both molecules. This leads to complex formation, thereby enhancing VEGFR-2 phosphorylation and subsequent signaling. We found that inhibition of VEGF receptor (VEGFR) phosphorylation reduced complex formation between NP-1 and VEGFR-2, suggesting a functional role of the cytoplasmic domain of VEGFR-2 for complex formation. Correspondingly, deleting the PDZ-binding domain of NP-1 decreased complex formation, indicating that extracellular VEGF(165) binding is not sufficient for VEGFR-2-NP-1 interaction. Synectin is an NP-1 PDZ-binding domain-interacting molecule. Experiments in Synectin-deficient endothelial cells revealed reduced VEGFR-2-NP-1 complex formation, suggesting a role for Synectin in VEGFR-2-NP-1 signaling. Taken together, the experiments have identified a novel mechanism of NP-1 interaction with VEGFR-2, which involves the cytoplasmic domain of NP-1.
Prahst
Claudia
C
Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany.
Héroult
Mélanie
M
Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany.
Lanahan
Anthony A
AA
Angiogenesis Research Center and Section of Cardiology, Department of Medicine, Dartmouth Medical School, Lebanon, New Hampshire 03756.
Uziel
Noa
N
Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel.
Kessler
Ofra
O
Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel.
Shraga-Heled
Niva
N
Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel.
Simons
Michael
M
Angiogenesis Research Center and Section of Cardiology, Department of Medicine, Dartmouth Medical School, Lebanon, New Hampshire 03756.
Neufeld
Gera
G
Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel.
Augustin
Hellmut G
HG
Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany. Electronic address: augustin@angiogenese.de.
D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry; D003593:Cytoplasm / Q000378:metabolism; D006801:Humans; D051379:Mice; D008954:Models, Biological; D009479:Neuropeptides / Q000737:chemistry; D039942:Neuropilin-1 / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D015398:Signal Transduction; D013552:Swine; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C492009:GIPC1 protein, human; C115271:Gipc1 protein, mouse; D009479:Neuropeptides; D042461:Vascular Endothelial Growth Factor A; D039942:Neuropilin-1; D040301:Vascular Endothelial Growth Factor Receptor-2