First published online January 25, 2008
Development 135, 402e (2008)
© The Company of Biologists Limited
Delivering an angiogenic role for netrin
The netrins are well-known neural guidance cues that can also direct blood
vessel growth. But the exact role of netrin 1 signalling in angiogenesis has
been under debate, with it being reported to have both anti-angiogenic and
angiogenic effects. To help resolve this issue, Dean Li's lab has now
conditionally inactivated the netrin receptor gene Unc5b specifically
in the embryonic endothelium of mice (see
p. 659). The only
detectable vascular abnormality in Unc5b mutant embryos, they report,
is a reduced number of placental labyrinthine arterioles, which leads to
increased placental resistance and to a fatal reversal of flow in the
umbilical artery. This phenotype cannot be rescued by wild-type trophectoderm
(from which extra-embryonic placental tissues derive), showing that
UNC5B-mediated signalling is a specific component of fetal placental
angiogenesis. The knockdown of Unc5b in zebrafish revealed a
similarly pro-angiogenic role, causing the specific loss of the parachordal
blood vessel. From their results, the authors suggest that UNC5B/netrin
signalling could be implicated in clinical uteroplacental insufficiency.
Related articles in Development:
- The netrin receptor UNC5B promotes angiogenesis in specific vascular beds
- Sutip Navankasattusas, Kevin J. Whitehead, Arminda Suli, Lise K. Sorensen, Amy H. Lim, Jia Zhao, Kye Won Park, Joshua D. Wythe, Kirk R. Thomas, Chi-Bin Chien, and Dean Y. Li
Development 2008 135: 659-667.
[Abstract]
[Full Text]
