Vasculature Growth - Tissue Functioning and Remodeling in the Circulatory and Ventilatory Systems - page 623

Table 10.11. Angiogenesis receptors and their ligands. Crosstalks between signaling effectors
allow to coordinate their spatial and temporal activities.

Receptor Ligand

VEGFR VEGF (endothelial cell)

Neuropilin Semaphorin

PDGFR PDGF (smooth myocyte)

HER EGF

FGFR FGF

TGFR TGF

TNFR TNF

EPH Ephrin

TIE Angiopoietin

S1PR S1P

Roundabout Slit

Netrin Uncoordinated-5

Galectin-1 Anginex

Nerve and vessel navigations to targets are subjected to a cooperative pro-
cedure, axonic and angiogenic signals guiding both vessels and axons. Ephrins,
semaphorins, netrins, and slits 29 control vessel morphogenesis.

10.6.1.1 Semaphorins

Semaphorin-3 Subtypes

During blood vessel genesis, endothelial cells produce semaphorin-3 that controls
integrin function for vascular reshaping [ 1209 ]. Semaphorin-3A expressed by
endothelial cells of developing vessels inhibits endothelial cell migration at nascent
adhesive sites of spreading endothelial cells, by interacting with integrins, such as
endostatin and thrombospondin.
Neuropilin-1 is a membrane receptor for multiple ligands 30 such as semaphorin-3
that regulates developmental process guidance [ 1210 , 1211 ].

cell receptors. Netrin-1 acts on both the endothelial cells and smooth myocytes of the vessel wall.
It can have repulsive and attractive effects, according to the context. Neogenin is expressed in
vascular smooth myocytes, whereas Unc5 is expressed in endothelial cells.
29 Slits are proteic chemorepellants in axon guidance and neuronal migration via the Roundabout
receptor. Robo1 is expressed by vascular endothelial cells. Slit2 attracts endothelial cells.
30 Neuropilin-1 and -2 that bind semaphorin-3A (or collapsin-1) are involved in axon guidance.
They are also receptors for heparin-binding VEGFa isoforms. Both Sema3a-Nrp1 and VEGF-
Nrp1 signaling are required for heart development.