First published online January 12, 2006
Development 133, 303e (2006)
© The Company of Biologists Limited
A new conserved role for Wnts in gastrulation?
During gastrulation, morphogenetic movements establish the three embryonic
cell layers. In sea urchins, secondary mesenchyme cells (SMC) at the vegetal
pole trigger the formation of the archenteron, the central cavity of the
gastrula that later develops into the primitive gut. On
p. 547, Croce and
co-workers report that a newly identified sea urchin Wnt receptor –
Frizzled (Fz) 5/8 – is required in SMCs to control archenteron
invagination. They show that Fz5/8 is expressed only in the animal domain and
in the SMCs during sea urchin embryogenesis. Loss-of-function analyses
indicate that Fz5/8 is not involved in the early specification of embryonic
cell types but is required to control the primary invagination of the
archenteron, which it does through the non-canonical planar cell polarity
pathway of Wnt signalling. The researchers suggest that Fz5/8 modulates the
morphogenetic movements that initiate gastrulation by controlling SMC
adhesion, shape and polarity, a mechanism that is likely to be conserved in
vertebrates.
Related articles in Development:
- Frizzled5/8 is required in secondary mesenchyme cells to initiate archenteron invagination during sea urchin development
- Jenifer Croce, Louise Duloquin, Guy Lhomond, David R. McClay, and Christian Gache
Development 2006 133: 547-557.
[Abstract]
[Full Text]
