|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
First published online October 27, 2004
doi: 10.1242/10.1242/dev.01428
Department of Neurobiology, Pharmacology and Physiology, Committees on Neurobiology and Developmental Biology, University of Chicago, 947 E 58th Street, MC0926, Chicago, IL 60637, USA
* Author for correspondence (e-mail: egrove{at}drugs.bsd.uchicago.edu)
Accepted 3 September 2004
Recent findings implicate embryonic signaling centers in patterning the mammalian cerebral cortex. We used mouse in utero electroporation and mutant analysis to test whether cortical signaling sources interact to regulate one another. We identified interactions between the cortical hem, rich in Wingless-Int (WNT) proteins and bone morphogenetic proteins (BMPs), and an anterior telencephalic source of fibroblast growth factors (FGFs).
Expanding the FGF8 domain suppressed Wnt2b, Wnt3a and Wnt5a expression in the hem. Next to the hem, the hippocampus was shrunken, consistent with its dependence for growth on a hem-derived WNT signal. Maintenance of hem WNT signaling and hippocampal development thus require a constraint on the FGF8 source, which is likely to be supplied by BMP activity. When endogenous BMP signaling is inhibited by noggin, robust Fgf8 expression appears ectopically in the cortical primordium.
Abnormal signaling centers were further investigated in mice lacking the transcription factor EMX2, in which FGF8 activity is increased, WNT expression reduced, and the hippocampus defective. Suggesting that these defects are causally related, sequestering FGF8 in Emx2 homozygous mutants substantially recovered WNT expression in the hem and partially rescued hippocampal development.
Because noggin can induce Fgf8 expression, we examined noggin and BMP signaling in the Emx2 mutant. As the telencephalic vesicle closed, Nog expression was expanded and BMP activity reduced, potentially leading to FGF8 upregulation. Our findings point to a cross-regulation of BMP, FGF, and WNT signaling in the early telencephalon, integrated by EMX2, and required for normal cortical development.
Key words: Cortical area map, In utero electroporation, Emx2 mutant mouse
This article has been cited by other articles:
![]() |
M. S. Brill, M. Snapyan, H. Wohlfrom, J. Ninkovic, M. Jawerka, G. S. Mastick, R. Ashery-Padan, A. Saghatelyan, B. Berninger, and M. Gotz A Dlx2- and Pax6-Dependent Transcriptional Code for Periglomerular Neuron Specification in the Adult Olfactory Bulb J. Neurosci., June 18, 2008; 28(25): 6439 - 6452. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. S. Mangale, K. E. Hirokawa, P. R. V. Satyaki, N. Gokulchandran, S. Chikbire, L. Subramanian, A. S. Shetty, B. Martynoga, J. Paul, M. V. Mai, et al. Lhx2 Selector Activity Specifies Cortical Identity and Suppresses Hippocampal Organizer Fate Science, January 18, 2008; 319(5861): 304 - 309. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Fernandes, G. Gutin, H. Alcorn, S. K. McConnell, and J. M. Hebert Mutations in the BMP pathway in mice support the existence of two molecular classes of holoprosencephaly Development, November 1, 2007; 134(21): 3789 - 3794. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. G. Rash and E. A. Grove Patterning the Dorsal Telencephalon: A Role for Sonic Hedgehog? J. Neurosci., October 24, 2007; 27(43): 11595 - 11603. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Huang, Y. Litingtung, and C. Chiang Ectopic sonic hedgehog signaling impairs telencephalic dorsal midline development: implication for human holoprosencephaly Hum. Mol. Genet., June 15, 2007; 16(12): 1454 - 1468. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. M. Benes, B. Lim, D. Matzilevich, J. P. Walsh, S. Subburaju, and M. Minns Regulation of the GABA cell phenotype in hippocampus of schizophrenics and bipolars PNAS, June 12, 2007; 104(24): 10164 - 10169. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. B. Glickstein, S. Alexander, and M. E. Ross Differences in Cyclin D2 and D1 Protein Expression Distinguish Forebrain Progenitor Subsets Cereb Cortex, March 1, 2007; 17(3): 632 - 642. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Menuet, A. Alunni, J.-S. Joly, W. R. Jeffery, and S. Retaux Expanded expression of Sonic Hedgehog in Astyanax cavefish: multiple consequences on forebrain development and evolution Development, March 1, 2007; 134(5): 845 - 855. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Inan and M. C. Crair Development of Cortical Maps: Perspectives From the Barrel Cortex Neuroscientist, February 1, 2007; 13(1): 49 - 61. [Abstract] [PDF] |
||||
![]() |
E. E. Storm, S. Garel, U. Borello, J. M. Hebert, S. Martinez, S. K. McConnell, G. R. Martin, and J. L. R. Rubenstein Dose-dependent functions of Fgf8 in regulating telencephalic patterning centers Development, May 1, 2006; 133(9): 1831 - 1844. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Barkovich, R. I. Kuzniecky, G. D. Jackson, R. Guerrini, and W. B. Dobyns A developmental and genetic classification for malformations of cortical development Neurology, December 27, 2005; 65(12): 1873 - 1887. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Sur and J. L. R. Rubenstein Patterning and Plasticity of the Cerebral Cortex Science, November 4, 2005; 310(5749): 805 - 810. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. E. Feldman and M. Brecht Map Plasticity in Somatosensory Cortex Science, November 4, 2005; 310(5749): 810 - 815. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. Langenfeld, J. Bojnowski, J. Perone, and J. Langenfeld Expression of Bone Morphogenetic Proteins in Human Lung Carcinomas Ann. Thorac. Surg., September 1, 2005; 80(3): 1028 - 1032. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. N. Sansom, J. M. Hebert, U. Thammongkol, J. Smith, G. Nisbet, M. A. Surani, S. K. McConnell, and F. J. Livesey Genomic characterisation of a Fgf-regulated gradient-based neocortical protomap Development, September 1, 2005; 132(17): 3947 - 3961. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Gotz and L. Sommer Cortical development: the art of generating cell diversity Development, August 1, 2005; 132(15): 3327 - 3332. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Muzio and A. Mallamaci Foxg1 Confines Cajal-Retzius Neuronogenesis and Hippocampal Morphogenesis to the Dorsomedial Pallium J. Neurosci., April 27, 2005; 25(17): 4435 - 4441. [Abstract] [Full Text] [PDF] |
||||