Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Mice lacking Dlx1 show subtype-specific loss of interneurons, reduced inhibition and epilepsy

Abstract

Dlx homeodomain transcription factors are essential during embryonic development for the production of forebrain GABAergic interneurons. Here we show that Dlx1 is also required for regulating the functional longevity of cortical and hippocampal interneurons in the adult brain. We demonstrate preferential Dlx1 expression in a subset of cortical and hippocampal interneurons which, in postnatal Dlx1 mutants, show a time-dependent reduction in number. This reduction preferentially affects calretinin+ (bipolar cells) and somatostatin+ subtypes (for example, bitufted cells), whereas parvalbumin+ subpopulations (basket cells and chandelier cells) seem to be unaffected. Cell transplantation analysis demonstrates that interneuron loss reflects cell-autonomous functions of Dlx1. The decrease in the number of interneurons was associated with a reduction of GABA-mediated inhibitory postsynaptic current in neocortex and hippocampus in vitro and cortical dysrhythmia in vivo. Dlx1 mutant mice show generalized electrographic seizures and histological evidence of seizure-induced reorganization, linking the Dlx1 mutation to delayed-onset epilepsy associated with interneuron loss.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Dlx1 is expressed in subsets of cortical and hippocampal GABAergic interneurons.
Figure 2: Number of GABAergic interneurons is reduced in neocortex and hippocampus of Dlx1−/− mice.
Figure 3: Subtype-specific reduction of interneurons in Dlx1−/− mice.
Figure 4: The reduction of GABAergic neurons in Dlx1−/− mice is due to apoptotic cell death.
Figure 5: Cell transplantation experiments show a cell-autonomous role for Dlx1 in controlling maturation and survival of subsets of cortical interneurons.
Figure 6: GABAergic synaptic inhibition is decreased in neocortex and hippocampus of Dlx1−/− mice.
Figure 7: Dlx1−/− mice have histological changes associated with seizures.
Figure 8: Dlx1−/− mice show cortical dysrhythmia and generalized electroencephalographic seizures.

Similar content being viewed by others

References

  1. Noebels, J.L. The biology of epilepsy genes. Annu. Rev. Neurosci. 26, 599–625 (2003).

    Article  CAS  PubMed  Google Scholar 

  2. Paulsen, O. & Moser, E.I. A model of hippocampal memory encoding and retrieval: GABAergic control of synaptic plasticity. Trends Neurosci. 21, 273–278 (1998).

    Article  CAS  PubMed  Google Scholar 

  3. Whittington, M.A. & Traub, R.D. Interneuron diversity series: inhibitory interneurons and network oscillations in vitro. Trends Neurosci. 26, 676–682 (2003).

    Article  CAS  PubMed  Google Scholar 

  4. Freund, T.F. Interneuron Diversity series: Rhythm and mood in perisomatic inhibition. Trends Neurosci. 26, 489–495 (2003).

    Article  CAS  PubMed  Google Scholar 

  5. Markram, H. et al. Interneurons of the neocortical inhibitory system. Nat. Rev. Neurosci. 5, 793–807 (2004).

    Article  CAS  PubMed  Google Scholar 

  6. Ramon y Cajal, S. Histology of the Nervous System. (Oxford University Press, New York, 1911).

    Google Scholar 

  7. Jones, E.G. Varieties and distribution of non-pyramidal cells in the somatic sensory cortex of the squirrel monkey. J. Comp. Neurol. 160, 205–267 (1975).

    Article  CAS  PubMed  Google Scholar 

  8. DeFelipe, J. Neocortical neuronal diversity: chemical heterogeneity revealed by colocalization studies of classic neurotransmitters, neuropeptides, calcium-binding proteins, and cell surface molecules. Cereb. Cortex 3, 273–289 (1993).

    Article  CAS  PubMed  Google Scholar 

  9. Kubota, Y., Hattori, R. & Yui, Y. Three distinct subpopulations of GABAergic neurons in rat frontal agranular cortex. Brain Res. 649, 159–173 (1994).

    Article  CAS  PubMed  Google Scholar 

  10. Gonchar, Y. & Burkhalter, A. Three distinct families of GABAergic neurons in rat visual cortex. Cereb. Cortex 7, 347–358 (1997).

    Article  CAS  PubMed  Google Scholar 

  11. McBain, C.J. & Fisahn, A. Interneurons unbound. Nat. Rev. Neurosci. 2, 11–23 (2001).

    Article  CAS  PubMed  Google Scholar 

  12. Gupta, A., Wang, Y. & Markram, H. Organizing principles for a diversity of GABAergic interneurons and synapses in the neocortex. Science 287, 273–278 (2000).

    Article  CAS  PubMed  Google Scholar 

  13. Klausberger, T. et al. Brain-state- and cell-type-specific firing of hippocampal interneurons in vivo. Nature 421, 844–848 (2003).

    Article  CAS  PubMed  Google Scholar 

  14. Lavdas, A.A., Grigoriou, M., Pachnis, V. & Parnavelas, J.G. The medial ganglionic eminence gives rise to a population of early neurons in the developing cerebral cortex. J. Neurosci. 19, 7881–7888 (1999).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Sussel, L., Marin, O., Kimura, S. & Rubenstein, J.L. Loss of Nkx2.1 homeobox gene function results in a ventral to dorsal molecular respecification within the basal telencephalon: evidence for a transformation of the pallidum into the striatum. Development 126, 3359–3370 (1999).

    CAS  PubMed  Google Scholar 

  16. Wichterle, H., Garcia-Verdugo, J.M., Herrera, D.G. & Alvarez-Buylla, A. Young neurons from medial ganglionic eminence disperse in adult and embryonic brain. Nat. Neurosci. 2, 461–466 (1999).

    Article  CAS  PubMed  Google Scholar 

  17. Xu, Q., Cobos, I., De La Cruz, E., Rubenstein, J.L. & Anderson, S.A. Origins of cortical interneuron subtypes. J. Neurosci. 24, 2612–2622 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Marin, O., Anderson, S.A. & Rubenstein, J.L. Origin and molecular specification of striatal interneurons. J. Neurosci. 20, 6063–6076 (2000).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Letinic, K., Zoncu, R. & Rakic, P. Origin of GABAergic neurons in the human neocortex. Nature 417, 645–649 (2002).

    Article  CAS  PubMed  Google Scholar 

  20. Panganiban, G. & Rubenstein, J.L. Developmental functions of the Distal-less/Dlx homeobox genes. Development 129, 4371–4386 (2002).

    CAS  PubMed  Google Scholar 

  21. Qiu, M. et al. Null mutation of Dlx-2 results in abnormal morphogenesis of proximal first and second branchial arch derivatives and abnormal differentiation in the forebrain. Genes Dev. 9, 2523–2538 (1995).

    Article  CAS  PubMed  Google Scholar 

  22. Qiu, M. et al. Role of the Dlx homeobox genes in proximodistal patterning of the branchial arches: mutations of Dlx-1, Dlx-2, and Dlx-1 and -2 alter morphogenesis of proximal skeletal and soft tissue structures derived from the first and second arches. Dev. Biol. 185, 165–184 (1997).

    Article  CAS  PubMed  Google Scholar 

  23. Anderson, S.A., Eisenstat, D.D., Shi, L. & Rubenstein, J.L. Interneuron migration from basal forebrain to neocortex: dependence on Dlx genes. Science 278, 474–476 (1997).

    Article  CAS  PubMed  Google Scholar 

  24. Cobos, I., Broccoli, V. & Rubenstein, J.L. The vertebrate ortholog of Aristaless is regulated by Dlx genes in the developing forebrain. J. Comp. Neurol. 483, 292–303 (2005).

    Article  CAS  PubMed  Google Scholar 

  25. Kitamura, K. et al. Mutation of ARX causes abnormal development of forebrain and testes in mice and X-linked lissencephaly with abnormal genitalia in humans. Nat. Genet. 32, 359–369 (2002).

    Article  CAS  PubMed  Google Scholar 

  26. Marty, S., Berzaghi Mda, P. & Berninger, B. Neurotrophins and activity-dependent plasticity of cortical interneurons. Trends Neurosci. 20, 198–202 (1997).

    Article  CAS  PubMed  Google Scholar 

  27. Stuhmer, T., Puelles, L., Ekker, M. & Rubenstein, J.L. Expression from a Dlx gene enhancer marks adult mouse cortical GABAergic neurons. Cereb. Cortex 12, 75–85 (2002).

    Article  PubMed  Google Scholar 

  28. Saino-Saito, S., Berlin, R. & Baker, H. Dlx-1 and Dlx-2 expression in the adult mouse brain: relationship to dopaminergic phenotypic regulation. J. Comp. Neurol. 461, 18–30 (2003).

    Article  CAS  PubMed  Google Scholar 

  29. Kawaguchi, Y. & Kubota, Y. GABAergic cell subtypes and their synaptic connections in rat frontal cortex. Cereb. Cortex 7, 476–486 (1997).

    Article  CAS  PubMed  Google Scholar 

  30. Alifragis, P., Liapi, A. & Parnavelas, J.G. Lhx6 regulates the migration of cortical interneurons from the ventral telencephalon but does not specify their GABA phenotype. J. Neurosci. 24, 5643–5648 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Alcantara, S. et al. Regional and cellular patterns of Reelin mRNA expression in the forebrain of the developing and adult mouse. J. Neurosci. 18, 7779–7799 (1998).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Erbel-Sieler, C. et al. Behavioral and regulatory abnormalities in mice deficient in the NPAS1 and NPAS3 transcription factors. Proc. Natl. Acad. Sci. USA 101, 13648–13653 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Stuhmer, T., Anderson, S.A., Ekker, M. & Rubenstein, J.L. Ectopic expression of the Dlx genes induces glutamic acid decarboxylase and Dlx expression. Development 129, 245–252 (2002).

    CAS  PubMed  Google Scholar 

  34. McBain, C.J., Eaton, J.V., Brown, T. & Dingledine, R. CNQX increases spontaneous inhibitory input to CA3 pyramidal neurones in neonatal rat hippocampal slices. Brain Res. 592, 255–260 (1992).

    Article  CAS  PubMed  Google Scholar 

  35. Morimoto, K., Fahnestock, M. & Racine, R.J. Kindling and status epilepticus models of epilepsy: rewiring the brain. Prog. Neurobiol. 73, 1–60 (2004).

    Article  CAS  PubMed  Google Scholar 

  36. Baraban, S.C. & Tallent, M.K. Interneuron Diversity series: Interneuronal neuropeptides–endogenous regulators of neuronal excitability. Trends Neurosci. 27, 135–142 (2004).

    Article  CAS  PubMed  Google Scholar 

  37. Racine, R.J. Modification of seizure activity by electrical stimulation. II. Motor seizure. Electroencephalogr. Clin. Neurophysiol. 32, 281–294 (1972).

    Article  CAS  PubMed  Google Scholar 

  38. Buzsaki, G. Theta oscillations in the hippocampus. Neuron 33, 325–340 (2002).

    Article  CAS  PubMed  Google Scholar 

  39. Nery, S., Fishell, G. & Corbin, J.G. The caudal ganglionic eminence is a source of distinct cortical and subcortical cell populations. Nat. Neurosci. 5, 1279–1287 (2002).

    Article  CAS  PubMed  Google Scholar 

  40. Yun, K. et al. Modulation of the notch signaling by Mash1 and Dlx1/2 regulates sequential specification and differentiation of progenitor cell types in the subcortical telencephalon. Development 129, 5029–5040 (2002).

    CAS  PubMed  Google Scholar 

  41. Powell, E.M. et al. Genetic disruption of cortical interneuron development causes region- and GABA cell type-specific deficits, epilepsy, and behavioral dysfunction. J. Neurosci. 23, 622–631 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Kobayashi, M. & Buckmaster, P.S. Reduced inhibition of dentate granule cells in a model of temporal lobe epilepsy. J. Neurosci. 23, 2440–2452 (2003).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Cossart, R. et al. Dendritic but not somatic GABAergic inhibition is decreased in experimental epilepsy. Nat. Neurosci. 4, 52–62 (2001).

    Article  CAS  PubMed  Google Scholar 

  44. Cossart, R., Bernard, C. & Ben-Ari, Y. Multiple facets of GABAergic neurons and synapses: multiple fates of GABA signalling in epilepsies. Trends Neurosci. 28, 108–115 (2005).

    Article  CAS  PubMed  Google Scholar 

  45. Maccaferri, G., Roberts, J.D., Szucs, P., Cottingham, C.A. & Somogyi, P. Cell surface domain specific postsynaptic currents evoked by identified GABAergic neurones in rat hippocampus in vitro. J. Physiol. (Lond.) 524, 91–116 (2000).

    Article  CAS  Google Scholar 

  46. Gonchar, Y., Turney, S., Price, J.L. & Burkhalter, A. Axo-axonic synapses formed by somatostatin-expressing GABAergic neurons in rat and monkey visual cortex. J. Comp. Neurol. 443, 1–14 (2002).

    Article  CAS  PubMed  Google Scholar 

  47. Wang, Y. et al. Anatomical, physiological and molecular properties of Martinotti cells in the somatosensory cortex of the juvenile rat. J. Physiol. (Lond.) 561, 65–90 (2004).

    Article  CAS  Google Scholar 

  48. Levitt, P., Eagleson, K.L. & Powell, E.M. Regulation of neocortical interneuron development and the implications for neurodevelopmental disorders. Trends Neurosci. 27, 400–406 (2004).

    Article  CAS  PubMed  Google Scholar 

  49. Horike, S., Cai, S., Miyano, M., Cheng, J.F. & Kohwi-Shigematsu, T. Loss of silent-chromatin looping and impaired imprinting of DLX5 in Rett syndrome. Nat. Genet. 37, 31–40 (2005).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

We thank R. Nicoll for physiological advice. I.C. thanks J. Palop and U. Borello for helpful discussions, M. Alvarez-Dolado for advice in cell transplantations, and the L. Mucke laboratory (Gladstone Institute of Neurological Disease, UCSF) for sharing the BioQuant Image Analysis. This work was supported by funds to J.L.R.R. (Nina Ireland, National Institute of Mental Health RO1 MH49428 and K05 MH065670), I.C. (National Alliance for Research on Schizophrenia and Depression Young Investigator Award), S.C.B. (US National Institutes of Health RO1 NS40272 and Citizens United for Research in Epilepsy) and J.L.N. (National Institute of Neurological Disorders and Stroke NS 29709 and National Institute of Child Health and Human Development HD24064, Baylor Mental Retardation and Developmental Disabilities Research Center).

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Inma Cobos or John L R Rubenstein.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Fig. 1

Normal numbers and layer distribution of Gad67+ neurons in postnatal Dlx1−/− mice. (PDF 4548 kb)

Supplementary Fig. 2

Normal numbers of PV+ interneurons in Dlx1−/− mice. (PDF 6893 kb)

Supplementary Fig. 3

Subtype-specific reduction of GABAergic neurons in Dlx1−/− mice. (PDF 7879 kb)

Supplementary Fig. 4

Preserved expression levels of interneuron markers in Dlx1−/− Dlx2−/− mice. (PDF 5743 kb)

Supplementary Fig. 5

Increased numbers of TUNEL+ profiles in neocortex and hippocampus of Dlx1−/− mice. (PDF 7061 kb)

Supplementary Fig. 6

Reduced GABAergic synaptic transmission in neocortex and hippocampus of Dlx1−/− mice. (PDF 1693 kb)

Supplementary Fig. 7

Distribution of amplitude and decay time constant of mIPSCs in Dlx1−/− mice. (PDF 2049 kb)

Supplementary Fig. 8

Expression of Dlx2 and Dlx5 in cortical interneurons. (PDF 6310 kb)

Supplementary Table 1

Decay time constant and rise time values of spontaneous and miniature IPSCs in neocortex and CA3 pyramidal cells from Dlx1+/+ and Dlx1−/− mice. (PDF 91 kb)

Supplementary Methods (PDF 174 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Cobos, I., Calcagnotto, M., Vilaythong, A. et al. Mice lacking Dlx1 show subtype-specific loss of interneurons, reduced inhibition and epilepsy. Nat Neurosci 8, 1059–1068 (2005). https://doi.org/10.1038/nn1499

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nn1499

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing