First published online October 12, 2007
Development 134, 2104e (2007)
© The Company of Biologists Limited
Divergent roles for reelin receptors revealed
The surface of the mammalian brain (the neocortex) contains six distinct
layers of neurons. The extracellular matrix protein reelin regulates the
migration of the neurons that form these layers. Reelin has two receptors:
very low density lipoprotein receptor (Vldlr) and apolipoprotein E receptor 2
(ApoER2). Now, Hack and colleagues reveal divergent roles for these two
receptors in the migration of cortical neurons (see
p. 3883). In mice,
the order of the cortical layers is inverted in reelin-knockout mutants and in
ApoER2 Vldlr double-knockout mutants; the phenotype of single-receptor
knockouts is much milder. To determine the specific role of each reelin
receptor in neuronal migration, the researchers mapped the fate of newly
generated cortical neurons in single and double receptor mutants. Their
results indicate that the proper migration of late-generated neurons, which
form the superficial layers of the neocortex, requires ApoER2. Vldlr, by
contrast, mediates a reelin stop signal that prevents neurons migrating into
the cell-poor marginal zone that covers the neocortex.
Related articles in Development:
- Divergent roles of ApoER2 and Vldlr in the migration of cortical neurons
- Iris Hack, Sabine Hellwig, Dirk Junghans, Bianka Brunne, Hans H. Bock, Shanting Zhao, and Michael Frotscher
Development 2007 134: 3883-3891.
[Abstract]
[Full Text]