VEGFR2 induces c-Src signaling and vascular permeability in vivo via the adaptor protein TSAd.
Regulation of vascular endothelial (VE) growth factor (VEGF)-induced permeability is critical in physiological and pathological processes. We show that tyrosine phosphorylation of VEGF receptor 2 (VEGFR2) at Y951 facilitates binding of VEGFR2 to the Rous sarcoma (Src) homology 2-domain of T cell-specific adaptor (TSAd), which in turn regulates VEGF-induced activation of the c-Src tyrosine kinase and vascular permeability. c-Src was activated in vivo and in vitro in a VEGF/TSAd-dependent manner, and was regulated via increased phosphorylation at pY418 and reduced phosphorylation at pY527. Tsad silencing blocked VEGF-induced c-Src activation, but did not affect pathways involving phospholipase Cγ, extracellular regulated kinase, and endothelial nitric oxide. VEGF-induced rearrangement of VE-cadherin-positive junctions in endothelial cells isolated from mouse lungs, or in mouse cremaster vessels, was dependent on TSAd expression, and TSAd formed a complex with VE-cadherin, VEGFR2, and c-Src at endothelial junctions. Vessels in tsad(-/-) mice showed undisturbed flow and pressure, but impaired VEGF-induced permeability, as measured by extravasation of Evans blue, dextran, and microspheres in the skin and the trachea. Histamine-induced extravasation was not affected by TSAd deficiency. We conclude that TSAd is required for VEGF-induced, c-Src-mediated regulation of endothelial cell junctions and for vascular permeability.
Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, 751 85 Uppsala, Sweden.
Zuyue
Z
Sun
Xiujuan
X
Li
Sara
S
Massena
Simone
S
Kutschera
Narendra
N
Padhan
Laura
L
Gualandi
Vibeke
V
Sundvold-Gjerstad
Karin
K
Gustafsson
Wing Wen
WW
Choy
Guangxiang
G
Zang
My
M
Quach
Leif
L
Jansson
Mia
M
Phillipson
Md Ruhul
MR
Abid
Anne
A
Spurkland
Lena
L
Claesson-Welsh
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D015153:Blotting, Western; D015820:Cadherins / Q000378:metabolism; D002199:Capillary Permeability / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000209:etiology; D005260:Female; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D008863:Microspheres; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding; D034622:RNA Interference; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*; D019061:src-Family Kinases / Q000378:metabolism*; D000099152:Cadherin 5
D048868:Adaptor Proteins, Signal Transducing; D015703:Antigens, CD; D015820:Cadherins; D016650:Fluorescein-5-isothiocyanate; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2; D019061:src-Family Kinases; D000099152:Cadherin 5; C402726:Sh2d2a protein, mouse