Regular Article
Pax6 Influences the Time and Site of Origin of Glial Precursors in the Ventral Neural Tube

https://doi.org/10.1006/mcne.1998.0711Get rights and content

Abstract

Neuroepithelial precursors in the ventral ventricular zone (VZ) of the spinal cord generate motor neurons (MNs) and interneurons, and then a subset of precursors starts to produce oligodendrocyte progenitors (OLPs). We show that OLPs originate in the ventral-most part of thePax6-positive VZ, which at earlier times generates somatic (Isl2/Lim3-positive) MNs. InSmall eye(Pax6-deficient) mice, the origin of OLPs is shifted dorsally and both OLPs andIsl2/Lim3MNs are delayed. We suggest that somatic MNs and OLPs are generated sequentially from a common set of MN-OL precursors whose position in the VZ is influenced by Pax6. Neuron–glia fate switching might be a preprogrammed property of these precursors or a response to feedback from newly generated neurons. OLs developed normally in explants ofIsl1(−/−)spinal cords, which lack MNs, arguing against feedback control and suggesting that the neuron–glia switch is an intrinsic developmental program in a specific subset of neural precursors.

References (48)

  • N.P. Pringle et al.

    Determination of neuroepithelial cell fate: Induction of the oligodendrocyte lineage by ventral midline cells and Sonic hedgehog

    Dev. Biol.

    (1996)
  • N.P. Pringle et al.

    Dorsal spinal cord neuroepithelium generates astrocytes but not oligodendrocytes

    Neuron

    (1998)
  • X. Qian et al.

    FGF2 concentration regulates the generation of neurons and glia from multipotent cortical stem cells

    Neuron

    (1997)
  • T. Tsuchida et al.

    Topographic organization of embryonic motor neurons defined by expression of LIM homeobox genes

    Cell

    (1994)
  • B.P. Williams et al.

    The generation of neurons and oligodendrocytes from a common precursor cell

    Neuron

    (1991)
  • W.-P. Yu et al.

    Embryonic expression of myelin genes: Evidence for a focal source of oligodendrocyte precursors in the ventricular zone of the neural tube

    Neuron

    (1994)
  • J. Altman et al.

    The development of the rat spinal cord

    Adv. Anat. Embryol. Cell Biol.

    (1984)
  • J.E. Bottenstein et al.

    Growth of a rat neuroblastoma cell line in serum-free supplemented medium

    Proc. Natl. Acad. Sci. USA

    (1979)
  • J.D. Burrill et al.

    PAX2 is expressed in multiple spinal cord interneurons, including a population of EN1+ interneurons that require PAX6 for their development

    Development

    (1997)
  • A.A. Davis et al.

    A self-renewing multipotential stem cell in embryonic rat cerebral cortex

    Nature

    (1994)
  • M. Ensini et al.

    The control of rostrocaudal pattern in the developing spinal cord: Specification of motor neuron subtype identity is initiated by signals from paraxial mesoderm

    Development

    (1998)
  • M.D. Goulding et al.

    Signals from the notochord and floor plate regulate the region-specific expression of two Pax genes in the developing spinal cord

    Development

    (1993)
  • R.J. Hardy

    Dorsoventral patterning and oligodendroglial specification in the developing central nervous system

    J. Neurosci.

    (1997)
  • Cited by (0)

    K. R. JessenW. D. Richardson

    1

    To whom correspondence and reprint requests should be addressed. Fax: +44 (0) 171 380 7805. E-mail:[email protected].

    View full text