Development 130, e1301 (2003)
Copyright © 2003 The Company of Biologists Limited
Evolutionary insights into skeletal development
In sea urchin embryogenesis, large blastomeres, called micromeres, and
their progeny act as an important signalling centre and give rise to
mesenchymal skeleton-forming cells. Ettensohn et al. have now identified a new
and essential component of the gene network that controls micromere
specification – Alx1, the first known invertebrate member of the
Cart1/Alx3/Alx4 family of vertebrate paired-class homeodomain proteins that
function in limb and craniofacial skeletal development. Morpholino knockdown
and gene expression experiments show that Alx1 controls genes required for
epithelial-mesenchymal transition and biomineralization. Importantly, these
findings, on p. 2917, hint at
an evolutionary link between certain features of skeletal development in
vertebrates and sea urchins, and indicate that the ancestral deuterostome from
which they derive might have had a mesenchymal cell lineage that engaged in
biomineralization, in which an Alx1-like protein functioned.
Related articles in Development:
- Alx1, a member of the Cart1/Alx3/Alx4 subfamily of Paired-class homeodomain proteins, is an essential component of the gene network controlling skeletogenic fate specification in the sea urchin embryo
- Charles A. Ettensohn, Michele R. Illies, Paola Oliveri, and Deborah L. De Jong
Development 2003 130: 2917-2928.
[Abstract]
[Full Text]
