RT Journal Article
SR Electronic
T1 Progeny of Olig2-Expressing Progenitors in the Gray and White Matter of the Adult Mouse Cerebral Cortex
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 10434
OP 10442
DO 10.1523/JNEUROSCI.2831-08.2008
VO 28
IS 41
A1 Leda Dimou
A1 Christiane Simon
A1 Frank Kirchhoff
A1 Hirohide Takebayashi
A1 Magdalena Götz
YR 2008
UL http://www.jneurosci.org/content/28/41/10434.abstract
AB Despite their abundance, still little is known about the rather frequent, constantly proliferating progenitors spread throughout the adult mouse brain parenchyma. The majority of these progenitors express the basic-helix-loop-helix transcription factor Olig2, and their number further increases after injury. Here, we examine the progeny of this progenitor population by genetic fate mapping using tamoxifen-inducible Cre-recombination in the Olig2 locus to turn on permanent reporter gene expression in the adult brain. Consistent with Olig2 expression in proliferating NG2+ progenitors, most reporter+ cells seen shortly after initiating recombination at adult stages incorporated BrdU and contained the proteoglycan NG2 in both the gray (GM) and the white matter (WM) of the cerebral cortex. However, at longer time points after induction, we observed profound differences in the identity of reporter+ cells in the WM and GM. Whereas most of the Olig2+ progenitors had generated mature, myelinating oligodendrocytes in the WM, hardly any reporter+ cells showing mature oligodendrocyte characteristics were detectable even up to 6 months after recombination in the GM. In the GM, most reporter+ cells remained NG2+, even after injury, but stopped proliferating rather soon after recombination. Thus, our results demonstrate the continuous generation of mature, myelinating oligodendrocytes in the WM, whereas cells in the GM generated mostly postmitotic NG2+ glia.