First published online September 7, 2007
Development 134, 1903e (2007)
© The Company of Biologists Limited
Neural patterning grid unlocked
The ascidian embryo, with its relative morphological simplicity, is an
excellent system in which to study cell fate specification. The Ciona
neural plate, for example, contains six rows and eight columns of aligned
cells, each with a unique molecular signature. Hudson and colleagues now
report that sequential and combinatorial inputs from Nodal, Delta2/Notch and
FGF/MEK/ERK signalling pathways establish this grid-like organization of
distinct cell identities (see
p. 3527). To study
cell fate specification in the posterior-most two rows of the neural plate,
the researchers used a combination of morpholino-based gene knockdown,
dominant-negative genes and pharmacological inhibitors. They show that Nodal
signalling first defines the medial and lateral neural plate domains. Delta2
signalling then subdivides each of these domains to generate four columns of
cells. Finally, FGF/MEK/ERK signalling along the anteroposterior axis promotes
row I fates and represses row II fates. Future studies, suggest the
researchers, have the potential to uncover the gene regulatory networks that
control the fate of each and every neural plate cell.
Related articles in Development:
- Sequential and combinatorial inputs from Nodal, Delta2/Notch and FGF/MEK/ERK signalling pathways establish a grid-like organisation of distinct cell identities in the ascidian neural plate
- Clare Hudson, Sonia Lotito, and Hitoyoshi Yasuo
Development 2007 134: 3527-3537.
[Abstract]
[Full Text]
