%0 Journal Article %J Duodecim Lääketieteellinen Aikakauskirja %D 2020 %T Lymphatics and the eye. [Finnish] %A Gucciardo, Erika %A Lehti, Timo A. %A Korhonen, Ani %A Salvén, Petri %A Lehti, Kaisa %A Jeltsch, Michael %A Loukovaara, Sirpa %B Duodecim Lääketieteellinen Aikakauskirja %V 136 %P 1777-1788 %8 2020/02/10/ %G eng %U https://www.duodecimlehti.fi/lehti/2020/16/duo15739 %N 16 %9 review %! Duodecim %& 1777 %R 10.5281/zenodo.4005517 %0 Journal Article %J Proceedings of the National Academy of Sciences of the United States of America %D 2010 %T Structural determinants of growth factor binding and specificity by VEGF receptor 2 %A Leppänen, Veli-Matti %A Prota, Andrea E %A Jeltsch, Michael %A Anisimov, Andrey %A Kalkkinen, Nisse %A Strandin, Tomas %A Lankinen, Hilkka %A Goldman, Adrian %A Ballmer-Hofer, Kurt %A Alitalo, Kari %X Vascular endothelial growth factors (VEGFs) regulate blood and lymph vessel formation through activation of three receptor tyrosine kinases, VEGFR-1, -2, and -3. The extracellular domain of VEGF receptors consists of seven immunoglobulin homology domains, which, upon ligand binding, promote receptor dimerization. Dimerization initiates transmembrane signaling, which activates the intracellular tyrosine kinase domain of the receptor. VEGF-C stimulates lymphangiogenesis and contributes to pathological angiogenesis via VEGFR-3. However, proteolytically processed VEGF-C also stimulates VEGFR-2, the predominant transducer of signals required for physiological and pathological angiogenesis. Here we present the crystal structure of VEGF-C bound to the VEGFR-2 high-affinity-binding site, which consists of immunoglobulin homology domains D2 and D3. This structure reveals a symmetrical 22 complex, in which left-handed twisted receptor domains wrap around the 2-fold axis of VEGF-C. In the VEGFs, receptor specificity is determined by an N-terminal alpha helix and three peptide loops. Our structure shows that two of these loops in VEGF-C bind to VEGFR-2 subdomains D2 and D3, while one interacts primarily with D3. Additionally, the N-terminal helix of VEGF-C interacts with D2, and the groove separating the two VEGF-C monomers binds to the D2/D3 linker. VEGF-C, unlike VEGF-A, does not bind VEGFR-1. We therefore created VEGFR-1/VEGFR-2 chimeric proteins to further study receptor specificity. This biochemical analysis, together with our structural data, defined VEGFR-2 residues critical for the binding of VEGF-A and VEGF-C. Our results provide significant insights into the structural features that determine the high affinity and specificity of VEGF/VEGFR interactions. %B Proceedings of the National Academy of Sciences of the United States of America %V 107 %P 2425 - 30 %8 02/2010 %G eng %U http://view.ncbi.nlm.nih.gov/pubmed/20145116 %N 6 %0 Journal Article %J J Cell Biol %D 2003 %T VEGF guides angiogenic sprouting utilizing endothelial tip cell filopodia %A Gerhardt, Holger %A Golding, Matthew %A Fruttiger, Marcus %A Ruhrberg, Christiana %A Lundkvist, Andrea %A Abramsson, Alexandra %A Jeltsch, Michael %A Mitchell, Christopher %A Alitalo, Kari %A Shima, David %A Betsholtz, Christer %X Vascular endothelial growth factor (VEGF-A) is a major regulator of blood vessel formation and function. It controls several processes in endothelial cells, such as proliferation, survival, and migration, but it is not known how these are coordinately regulated to result in more complex morphogenetic events, such as tubular sprouting, fusion, and network formation. We show here that VEGF-A controls angiogenic sprouting in the early postnatal retina by guiding filopodial extension from specialized endothelial cells situated at the tips of the vascular sprouts. The tip cells respond to VEGF-A only by guided migration; the proliferative response to VEGF-A occurs in the sprout stalks. These two cellular responses are both mediated by agonistic activity of VEGF-A on VEGF receptor 2. Whereas tip cell migration depends on a gradient of VEGF-A, proliferation is regulated by its concentration. Thus, vessel patterning during retinal angiogenesis depends on the balance between two different qualities of the extracellular VEGF-A distribution, which regulate distinct cellular responses in defined populations of endothelial cells. %B J Cell Biol %V 161 %P 1163 - 77 %8 2003/Jun/ %G eng %U http://view.ncbi.nlm.nih.gov/pubmed/12810700 %N 6 %! The Journal of Cell Biology %0 Journal Article %J Proc Natl Acad Sci U S A %D 1998 %T Vascular endothelial growth factor B (VEGF-B) binds to VEGF receptor-1 and regulates plasminogen activator activity in endothelial cells %A Olofsson, B %A Korpelainen, E %A Pepper, M S %A Mandriota, S J %A Aase, K %A Kumar, V %A Gunji, Y %A Jeltsch, M M %A Shibuya, M %A Alitalo, K %A Eriksson, U %X The vascular endothelial growth factor (VEGF) family has recently expanded by the identification and cloning of three additional members, namely VEGF-B, VEGF-C, and VEGF-D. In this study we demonstrate that VEGF-B binds selectively to VEGF receptor-1/Flt-1. This binding can be blocked by excess VEGF, indicating that the interaction sites on the receptor are at least partially overlapping. Mutating the putative VEGF receptor-1/Flt-1 binding determinants Asp63, Asp64, and Glu67 to alanine residues in VEGF-B reduced the affinity to VEGF receptor-1 but did not abolish binding. Mutational analysis of conserved cysteines contributing to VEGF-B dimer formation suggest a structural conservation with VEGF and platelet-derived growth factor. Proteolytic processing of the 60-kDa VEGF-B186 dimer results in a 34-kDa dimer containing the receptor-binding epitopes. The binding of VEGF-B to its receptor on endothelial cells leads to increased expression and activity of urokinase type plasminogen activator and plasminogen activator inhibitor 1, suggesting a role for VEGF-B in the regulation of extracellular matrix degradation, cell adhesion, and migration. %B Proc Natl Acad Sci U S A %V 95 %P 11709 - 14 %8 1998/Sep/ %G eng %U http://view.ncbi.nlm.nih.gov/pubmed/9751730 %N 20 %! Proceedings of the National Academy of Sciences of the United States of America