First published online August 11, 2005
Development 132, 1701e (2005)
© The Company of Biologists Limited
Protomapping the route to the neocortex
In the mammalian neocortex, different areas have different functions. One
model for the formation of this modular structure proposes that neocortical
progenitor cells become patterned by extracellular signals to generate a
protomap of progenitor cell areas that are defined by their gene expression
patterns, which, in turn, generate area-specific neurons. On
p. 3947, Sansom and
co-workers provide important insights into the nature of this proposed
protomap by systematically analysing gene expression patterns in the
developing mouse neocortex. Their results provide little evidence to support
the division of neocortical progenitor cells into discrete domains, as seen in
the developing spinal cord. Instead, the early neocortical protomap appears to
be composed of gradients of gene expression along the rostrocaudal axis.
Through their examination of gene expression changes in mutant Fgfr1
and Mest (which encodes a mesoderm-specific gene) mice, the
researchers show that the formation of the protomap is Fgf-regulated and
influenced by Mest.
Related articles in Development:
- Genomic characterisation of a Fgf-regulated gradient-based neocortical protomap
- Stephen N. Sansom, Jean M. Hébert, Uruporn Thammongkol, James Smith, Grace Nisbet, M. Azim Surani, Susan K. McConnell, and Frederick J. Livesey
Development 2005 132: 3947-3961.
[Abstract]
[Full Text]