First published online May 23, 2006
Development 133, 1205e (2006)
© The Company of Biologists Limited
Fgf10 from somite to breast
To date, it has remained unclear what signals subdivide the surface
ectoderm of embryos into different developmental fields, such as those that
form mammary epithelium. But now, on p.
2325, Veltmaat et al.
reveal that the induction and positioning of one of the five mammary placodes
in the mouse depends on Gli3-mediated somitic Fgf10
expression gradients, which activate ectodermally expressed FGF receptors and
lead to Wnt10b expression. Using Wnt signalling and ectodermal
multilayering as markers of mammogenesis, the researchers investigated mammary
placode development in mouse mutants with altered somitic Fgf10
gradients. They report that mammary line formation is impaired and placode 3
is absent in embryos in which the somitic Fgf10 gradient is shortened
(as in Gli3 null embryos) or less Fgf10 is expressed
overall. The researchers suggest, therefore, that a combination of somitic
elongation and somitic Fgf10 gradients induces the differentiation of
the surface ectoderm into mammary epithelium at the position in mice that
corresponds to the position of the human breast.
Related articles in Development:
- Gli3-mediated somitic Fgf10 expression gradients are required for the induction and patterning of mammary epithelium along the embryonic axes
- Jacqueline M. Veltmaat, Frédéric Relaix, Lendy T. Le, Klaus Kratochwil, Frédéric G. Sala, Wendy van Veelen, Ritva Rice, Bradley Spencer-Dene, Arnaud A. Mailleux, David P. Rice, Jean Paul Thiery, and Saverio Bellusci
Development 2006 133: 2325-2335.
[Abstract]
[Full Text]
