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A critical role for sonic hedgehog signaling in the early expansion of the developing brain

Nature Neuroscience volume 5, pages 103–110 (2002)Cite this article

Abstract

The mechanisms that coordinate the three-dimensional shape of the vertebrate brain during development are largely unknown. We have found that sonic hedgehog (Shh) is crucial in driving the rapid, extensive expansion of the early vesicles of the developing midbrain and forebrain. Transient displacement of the notochord from the midbrain floor plate resulted in abnormal folding and overall collapse of the vesicles, accompanied by reduced cell proliferation and increased cell death in the midbrain. Simultaneously, expression of Shh decreased locally in the notochord and floor plate, whereas overt patterning and differentiation proceeded normally. Normal midbrain expansion was restored by implantation of Shh-secreting cells in a dose-dependent manner; conversely, expansion was retarded following antagonism of the Shh signaling pathway by cyclopamine. Our results indicate that Shh signaling from the ventral midline is essential for regulating brain morphogenesis during early development.

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Figure 1: Transient separation of the notochord causes abnormal brain morphogenesis.
Figure 2: Overt differentiation of the brain is unaffected following notochord manipulation.
Figure 3: Loss of Shh expression after separation of the notochord.
Figure 4: Expression of genes involved in development of the MHB region following notochord separation at stage 12.
Figure 5: Reduced proliferation and increased cell death in the neural tube after notochord separation.
Figure 6: Rescue of normal phenotype by ectopic expression of Shh.

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References

  1. Brown, M., Keynes, R. & Lumsden, A. The Developing Brain (Oxford University Press, Oxford, 2001).

  2. Källén, B. Proliferation in the embryonic brain with special reference to the overgrowth phenomenon and its possible relationship to neoplasia. Prog. Brain Res. 14, 263–278 (1965).

    Article  Google Scholar 

  3. Burda, D. J. Studies on the experimental induction of overgrowth in chick embryos. Anat. Rec. 161, 419–426 (1968).

    Article  CAS  PubMed  Google Scholar 

  4. Wilson, D. The cell cycle of ventricular cells in the overgrown optic tectum. Brain Res. 69, 41–48 (1974).

    Article  CAS  PubMed  Google Scholar 

  5. Hamburger, V. & Hamilton, H. G. A series of normal stages in the development of the chick embryo. J. Morphol. 88, 49–92 (1951).

    Article  CAS  PubMed  Google Scholar 

  6. Wilson, D. B. Sequence of neuron origin in experimentally distorted brains of chick embryos. J. Comp. Neurol. 180, 501–508 (1978).

    Article  CAS  PubMed  Google Scholar 

  7. Alvarado-Mallart, R. M. Fate and potentialities of the avian mesencephalic/metencephalic neuroepithelium. J. Neurobiol. 24, 1341–1355 (1993).

    Article  CAS  PubMed  Google Scholar 

  8. Liu, A. & Joyner, A. L. Early anterior/posterior patterning of the midbrain and cerebellum. Annu. Rev. Neurosci. 24, 869–896 (2001).

    Article  CAS  PubMed  Google Scholar 

  9. Jessell, T. M. Neuronal specification in the spinal cord: inductive signals and transcriptional codes. Nat. Rev. Genet. 1, 20–29 (2000).

    Article  CAS  PubMed  Google Scholar 

  10. Shamim, H. et al. Sequential roles for Fgf4, En1 and Fgf8 in specification and regionalisation of the midbrain. Development 126, 945–959 (1999).

    CAS  PubMed  Google Scholar 

  11. Echelard, Y. et al. Sonic hedgehog, a member of a family of putative signaling molecules, is implicated in the regulation of CNS polarity. Cell 75, 1417–1430 (1993).

    Article  CAS  PubMed  Google Scholar 

  12. Roelink, H. et al. Floor plate and motor neuron induction by vhh-1, a vertebrate homolog of hedgehog expressed by the notochord. Cell 76, 761–775 (1994).

    Article  CAS  PubMed  Google Scholar 

  13. Ruiz-i-Altaba, A., Placzek, M., Baldassare, M., Dodd, J. & Jessell, T. M. Early stages of notochord and floor plate development in the chick embryo defined by normal and induced expression of HNF-3 beta. Dev. Biol. 170, 299–313 (1995).

    Article  PubMed  Google Scholar 

  14. Epstein, D. J., McMahon, A. P. & Joyner, A. L. Regionalization of Sonic hedgehog transcription along the anteroposterior axis of the mouse central nervous system is regulated by Hnf3-dependent and -independent mechanisms. Development 126, 281–292 (1999).

    CAS  PubMed  Google Scholar 

  15. Yamada, T., Pfaff, S. L., Edlund, T. & Jessell, T. M. Control of cell pattern in the neural tube: motor neuron induction by diffusible factors from notochord and floor plate. Cell 73, 673–686 (1993).

    Article  CAS  PubMed  Google Scholar 

  16. Varela-Echavarría, A., Pfaff, S. L. & Guthrie, S. Differential expression of LIM homeobox genes among motor neuron subpopulations in the developing chick brain stem. Mol. Cell Neurosci. 8, 242–257 (1996).

    Article  PubMed  Google Scholar 

  17. Hollyday, M., McMahon, J. A. & McMahon, A. P. Wnt expression patterns in chick embryo nervous system. Mech. Dev. 52, 9–25 (1995).

    Article  CAS  PubMed  Google Scholar 

  18. Lee, S. M., Danielian, P. S., Fritzsch, B. & McMahon, A. P. Evidence that FGF8 signalling from the midbrain–hindbrain junction regulates growth and polarity in the developing midbrain. Development 124, 959–969 (1997).

    CAS  PubMed  Google Scholar 

  19. Vaccarino, F. M. et al. Changes in the cerebral cortex size are governed by fibroblast growth factor during development. Nat. Neurosci. 2, 246–253 (1999).

    Article  CAS  PubMed  Google Scholar 

  20. Shamim, H. & Mason, I. Expression of Fgf4 during early development of the chick embryo. Mech. Dev. 85, 189–192 (1999).

    Article  CAS  PubMed  Google Scholar 

  21. Walshe, J. & Mason, I. Expression of FGFR1, FGFR2 and FGFR3 during early neural development in the chick embryo. Mech. Dev. 90, 103–110 (2000).

    Article  CAS  PubMed  Google Scholar 

  22. Cooper, M. K., Porter, J. A., Young, K. E. & Beachy, P. A. Teratogen-mediated inhibition of target tissue response to Shh signaling. Science 280, 1603–1607 (1998).

    Article  CAS  PubMed  Google Scholar 

  23. Incardona, J. P., Gaffield, W., Kapur, R. P. & Roelink, H. The teratogenic Veratrum alkaloid cyclopamine inhibits sonic hedgehog signal transduction. Development 125, 3553–3562 (1998).

    CAS  PubMed  Google Scholar 

  24. Desmond, M. E. & Jacobson, A. G. Embryonic brain enlargement requires cerebrospinal fluid pressure. Dev. Biol. 57, 188–198 (1977).

    Article  CAS  PubMed  Google Scholar 

  25. Desmond, M. E. & Schoenwolf, G. C. Evaluation of the roles of intrinsic and extrinsic factors in occlusion of the spinal neurocoel during rapid brain enlargement in the chick embryo. J. Embryol. Exp. Morphol. 97, 25–46 (1986).

    CAS  PubMed  Google Scholar 

  26. Watanabe, Y. & Nakamura, H. Control of chick tectum territory along dorsoventral axis by Sonic hedgehog. Development 127, 1131–1140 (2000).

    CAS  PubMed  Google Scholar 

  27. Agarwala, S., Sanders, T. A. & Ragsdale, C. W. Sonic hedgehog control of size and shape in midbrain pattern formation. Science 291, 2147–2150 (2001).

    Article  CAS  PubMed  Google Scholar 

  28. Jensen, A. M. & Wallace, V. A. Expression of Sonic hedgehog and its putative role as a precursor cell mitogen in the developing mouse retina. Development 124, 363–371 (1997).

    CAS  PubMed  Google Scholar 

  29. Duprez, D., Fournier-Thibault, C. & Le Douarin, N. Sonic hedgehog induces proliferation of committed skeletal muscle cells in the chick limb. Development 125, 495–505 (1998).

    CAS  PubMed  Google Scholar 

  30. Wallace, V. A. & Raff, M. C. A role for Sonic hedgehog in axon-to-astrocyte signalling in the rodent optic nerve. Development 126, 2901–2909 (1999).

    CAS  PubMed  Google Scholar 

  31. Dahmane, N. & Ruiz-i-Altaba, A. Sonic hedgehog regulates the growth and patterning of the cerebellum. Development 126, 3089–3100 (1999).

    PubMed  Google Scholar 

  32. Wallace, V. A. Purkinje-cell-derived Sonic hedgehog regulates granule neuron precursor cell proliferation in the developing mouse cerebellum. Curr. Biol. 9, 445–448 (1999).

    Article  CAS  PubMed  Google Scholar 

  33. Wechsler-Reya, R. J. & Scott, M. P. Control of neuronal precursor proliferation in the cerebellum by Sonic Hedgehog. Neuron 22, 103–114 (1999).

    Article  CAS  PubMed  Google Scholar 

  34. Ahlgren, S. C. & Bronner-Fraser, M. Inhibition of Sonic hedgehog signaling in vivo results in craniofacial neural crest cell death. Curr. Biol. 9, 1304–1314 (1999).

    Article  CAS  PubMed  Google Scholar 

  35. Rowitch, D. H. et al. Sonic hedgehog regulates proliferation and inhibits differentiation of CNS precursor cells. J. Neurosci. 19, 8954–8965 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  36. Sanz-Ezquerro, J. J. & Tickle, C. Autoregulation of Shh expression and Shh induction of cell death suggest a mechanism for modulating polarising activity during chick limb development. Development 127, 4811–4823 (2000).

    CAS  PubMed  Google Scholar 

  37. Miao, N. et al. Sonic hedgehog promotes the survival of specific CNS neuron populations and protects these cells from toxic insultin vitro. J. Neurosci. 17, 5891–5899 (1997).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Teillet, M. et al. Sonic hedgehog is required for survival of both myogenic and chondrogenic somitic lineages. Development 125, 2019–2030 (1998).

    CAS  PubMed  Google Scholar 

  39. Borycki, A. G. et al. Sonic hedgehog controls epaxial muscle determination through Myf5 activation. Development 126, 4053–4063 (1999).

    CAS  PubMed  Google Scholar 

  40. Charrier, J. B., Lapointe, F., Douarin, N. M. & Teillet, M. A. Anti-apoptotic role of Sonic hedgehog protein at the early stages of nervous system organogenesis. Development 128, 4011–4020 (2001).

    CAS  PubMed  Google Scholar 

  41. Marti, E., Takada, R., Bumcrot, D. A., Sasaki, H. & McMahon, A. P. Distribution of Sonic hedgehog peptides in the developing chick and mouse embryo. Development 121, 2537–2547 (1995).

    CAS  PubMed  Google Scholar 

  42. Carl, M. & Wittbrodt, J. Graded interference with FGF signalling reveals its dorsoventral asymmetry at the mid–hindbrain boundary. Development 126, 5659–5667 (1999).

    CAS  PubMed  Google Scholar 

  43. Niswander, L., Jeffrey, S., Martin, G. R. & Tickle, C. A positive feedback loop coordinates growth and patterning in the vertebrate limb. Nature 371, 609–612 (1994).

    Article  CAS  PubMed  Google Scholar 

  44. Zuniga, A., Haramis, A. P., McMahon, A. P. & Zeller, R. Signal relay by BMP antagonism controls the SHH/FGF4 feedback loop in vertebrate limb buds. Nature 401, 598–602 (1999).

    Article  CAS  PubMed  Google Scholar 

  45. Sun, X. et al. Conditional inactivation of Fgf4 reveals complexity of signalling during limb bud development. Nat. Genet. 25, 83–86 (2000).

    Article  CAS  PubMed  Google Scholar 

  46. Marigo, V. & Tabin, C. J. Regulation of patched by sonic hedgehog in the developing neural tube. Proc. Natl. Acad. Sci. USA 93, 9346–9351 (1996).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  47. Nieto, M. A., Patel, K. & Wilkinson, D. G. In situ hybridization analysis of chick embryos in whole mount and tissue sections. Methods Cell Biol. 51, 219–235 (1996).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

This work was supported by a Cambridge Australia Scholarship, the Cambridge Commonwealth Trust and a Peter Doherty Fellowship (J.B.), a Royal Society University Research Fellowship (D.T.), an International Research Scholars award from the Howard Hughes Medical Institute (R.K.), and by grants from the Medical Research Council and Wellcome Trust. We thank A. Fleming for comments on the manuscript.

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  1. Joanne Britto

    Present address: Neurotrauma Research Program, WAIMR, MRF Building, Perth, 6000, Australia

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  1. Department of Anatomy, University of Cambridge, Downing Street, Cambridge, CB2 3DY, UK

    Joanne Britto, David Tannahill & Roger Keynes

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Correspondence to Roger Keynes.

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Britto, J., Tannahill, D. & Keynes, R. A critical role for sonic hedgehog signaling in the early expansion of the developing brain. Nat Neurosci 5, 103–110 (2002). https://doi.org/10.1038/nn797

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