Conversion of cerebral cortex into basal ganglia in Emx2−/− Pax6Sey/Sey double-mutant mice

  • A Corrigendum to this article was published on 22 November 2013


The molecular mechanisms that activate morphogenesis of cerebral cortex are currently the subject of intensive experimental analysis. Transcription factor genes of the homeobox, basic helix-loop-helix (bHLH) and zinc-finger families have recently been shown to have essential roles in this process. However, the actual selector genes activating corticogenesis have not yet been identified. Here we show that high-level expression of at least one functional allele of either of the homeobox genes Emx2 or Pax6 in the dorsal telencephalon is necessary and sufficient to stably activate morphogenesis of cerebral cortex and to repress that of adjacent structures, such as striatum.

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Figure 1: Hematoxylin staining of Emx2 Pax6 mutant telencephalons.
Figure 2: Downregulation of cortical markers in late gestation Emx2 Pax6 mutants.
Figure 3: Ectopic expression of basal ganglia markers in the cortex of late gestation Emx2 Pax6 mutants.
Figure 4: Spreading of cortical hem identities in the cortex of late gestation Emx2 Pax6 mutants.
Figure 5: Downregulation of cortical markers in mid-gestation Emx2 Pax6 mutants.
Figure 6: Ectopic expression of ventral markers in the cortical anlage of mid gestation Emx2 Pax6 mutants.
Figure 7: Colocalization of BrdU and Islet1 in the telencephalon of an E11.5 Emx2−/− Pax6−/− mutant embryo, administered with BrdU and killed after 8 h.
Figure 8: Vitality and cortical-ganglionic specification of neuroblasts, in the dorsal telencephalon of Emx2 Pax6 mid-gestation mutants.

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  • 07 February 2012

    In the version of this article initially published, author Barbara Di Benedetto's name was misspelled. The error has been corrected in the HTML and PDF versions of the article.


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We thank J. Parnavelas, P. Bovolenta and A. Bulfone for critical reading of the manuscript. This work was funded by the EU (QLG3-CT-2000-00158; QLG3-CT-2000-01625; HPRN-CT-2000-00097), the Italian Ministery of Health (CS030.5/RF00.73), the Italian National Research Council (PF01.00026.PF49) and the University Excellence Center on Physiopathology of Cell.

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Correspondence to Antonello Mallamaci.

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Muzio, L., Di Benedetto, B., Stoykova, A. et al. Conversion of cerebral cortex into basal ganglia in Emx2−/− Pax6Sey/Sey double-mutant mice. Nat Neurosci 5, 737–745 (2002).

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