title: Orf virus VEGF-E NZ2 promotes paracellular NRP-1/VEGFR-2 coreceptor assembly via the peptide RPPR.
abstract: Vascular endothelial growth factors (VEGFs) interact with the receptor tyrosine kinases (RTKs) VEGFR-1, -2, and -3; neuropilins (NRPs); and heparan sulfate (HS) proteoglycans. VEGF RTKs signal to downstream targets upon ligand-induced tyrosine phosphorylation, while NRPs and HS act as coreceptors that lack enzymatic activity yet modulate signal output by VEGF RTKs. VEGFs exist in various isoforms with distinct receptor specificity and biological activity. Here, a series of mammalian VEGF-A splice variants and orf virus VEGF-Es, as well as chimeric and mutant VEGF variants, were characterized to determine the motifs required for binding to NRP-1 in the absence (VEGF-E) or presence (VEGF-A(165)) of an HS-binding sequence. We identified the carboxyterminal peptides RPPR and DKPRR as the NRP-1 binding motifs of VEGF-E and VEGF-A, respectively. RPPR had significantly higher affinity for NRP-1 than DKPRR. VEGFs containing an RPPR motif promoted HS-independent coreceptor complex assembly between VEGFR-2 and NRP-1, independent of whether these receptors were expressed on the same or separate cells grown in cocultures. Functional studies showed that stable coreceptor assembly by VEGF correlated with its ability to promote vessel formation in an embryoid body angiogenesis assay.
authors.affiliation: Paul Scherrer Institut, Laboratory of Biomolecular Research, Molecular Cell Biology, 5232 Villigen-PSI Switzerland.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Cébe-Suarez
authors.forename: Felix S
authors.initials: FS
authors.lastname: Grünewald
authors.forename: Rolf
authors.initials: R
authors.lastname: Jaussi
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Li
authors.forename: Lena
authors.initials: L
authors.lastname: Claesson-Welsh
authors.forename: Dorothe
authors.initials: D
authors.lastname: Spillmann
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Mercer
authors.forename: Andrea E
authors.initials: AE
authors.lastname: Prota
authors.forename: Kurt
authors.initials: K
authors.lastname: Ballmer-Hofer
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D053595:Embryonic Stem Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes; D018919:Neovascularization, Physiologic / Q000187:drug effects; D039942:Neuropilin-1 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism*; D009923:Orf virus / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011817:Rabbits; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D046912:Multiprotein Complexes; D009842:Oligopeptides; D011994:Recombinant Proteins; C084758:VEGF-like protein, Orf virus; D042461:Vascular Endothelial Growth Factor A; D014764:Viral Proteins; D039942:Neuropilin-1; D040301:Vascular Endothelial Growth Factor Receptor-2