Complete structure of an increasing capillary permeability protein (ICPP) purified from Vipera lebetina venom. ICPP is angiogenic via vascular endothelial growth factor receptor signalling.
The partial sequence of the increasing capillary permeability protein (ICPP) purified from Vipera lebetina venom revealed a strong homology to vascular endothelial growth factor (VEGF)-A. We now report its complete amino acid sequence determined by Edman degradation and its biological effects on mouse and human vascular endothelial cells. ICPP is a homodimeric protein linked by cysteine disulfide bonds of 25115 Da revealed by mass spectrometry. Each monomer is composed of 110 amino acids including eight cysteine residues and a pyroglutamic acid at the N-terminal extremity. ICPP shares 52% sequence identity with human VEGF but lacks the heparin binding domain and Asn glycosylation site. Besides its strong capillary permeability activity, ICPP was found to be a potent in vitro angiogenic factor when added to mouse embryonic stem cells or human umbilical vein endothelial cells. ICPP was found to be as potent as human VEGF165 in activating p42/p44 MAPK, in reinitiation of DNA synthesis in human umbilical vein endothelial cells, and in promoting in vitro angiogenesis of mouse embryonic stem cells. All these biological actions, including capillary permeability in mice, were fully inhibited by 1 microm of a new specific VEGF receptor tyrosine kinase inhibitor (ZM317450) from AstraZeneca that belongs to the anilinocinnoline family of compounds. Indeed, up to a 30 times higher concentration of inhibitor did not affect platelet-derived growth factor, epidermal growth factor, FGF-2, insulin, alpha-thrombin, or fetal calf serum-induced p42/p44 MAPK and reinitiation of DNA synthesis. Therefore, we conclude that this venom-derived ICPP exerts its biological action (permeability and angiogenesis) through activation of VEGF receptor signaling (VEGF-R2 and possibly VEGF-R1).
Gasmi
Ammar
A
Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, B. P. 74, 1002 Tunis-Belvedère, Tunisia. ammar.gasmi@pasteur.rns.tn
Bourcier
Christine
C
Aloui
Zohra
Z
Srairi
Najet
N
Marchetti
Sandrine
S
Gimond
Clotilde
C
Wedge
Stephen R
SR
Hennequin
Laurent
L
Pouysségur
Jacques
J
D000595:Amino Acid Sequence; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects*; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D011506:Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000494:pharmacology; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D017978:Receptors, Growth Factor / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014757:Viper Venoms / Q000737:chemistry*; D017819:Viperidae
D004791:Enzyme Inhibitors; D011506:Proteins; D017978:Receptors, Growth Factor; D014757:Viper Venoms; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor