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From synapse to behavior: rapid modulation of defined neuronal types with engineered GABAA receptors

Nature Neuroscience volume 10, pages 923929 (2007) | Download Citation

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Abstract

In mammals, identifying the contribution of specific neurons or networks to behavior is a key challenge. Here we describe an approach that facilitates this process by enabling the rapid modulation of synaptic inhibition in defined cell populations. Binding of zolpidem, a systemically active allosteric modulator that enhances the function of the GABAA receptor, requires a phenylalanine residue (Phe77) in the γ2 subunit. Mice in which this residue is changed to isoleucine are insensitive to zolpidem. By Cre recombinase–induced swapping of the γ2 subunit (that is, exchanging Ile77 for Phe77), zolpidem sensitivity can be restored to GABAA receptors in chosen cell types. We demonstrate the power of this method in the cerebellum, where zolpidem rapidly induces significant motor deficits when Purkinje cells are made uniquely sensitive to its action. This combined molecular and pharmacological technique has demonstrable advantages over targeted cell ablation and will be invaluable for investigating many neuronal circuits.

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Acknowledgements

We thank E. Sigel for pointing out the γ2I77 mutation; J. Oberdick for the L7 expression cassette; S.J. Moss for the γ2F77GFP plasmid; M. Meyer for the L7Cre line; R. Tomioka and E. Mugnaini for antibodies to EGFP and GAD, respectively; H. Monyer for discussion and support; F. Zimmermann for the transgene and stem cell injections; I. Preugschat-Gumprecht for help with mouse genotyping; D. Andersson, T. Karayannis and M. Capogna for contributing to initial electrophysiological recordings; and S. Brickley, M. Capogna, S.G. Cull-Candy, C. De Zeeuw, N. Franks, T. Klausberger and Z. Nusser for comments on the manuscript. This work was funded by the VolkswagenStiftung (grant I/78 554 to W.W., E.R.K., W.S. and P.S.), the Deutsche Forschungsgemeinschaft (grant WI 1951/2 to W.W. and P.W.), the UK Medical Research Council (grant G0501584 to W.W.), the J. Ernest Tait Estate (to W.W. and T.G.), a Heidelberg Young Investigator Award (to P.W.), the Academy of Finland (to E.R.K. and A.-M.L.), the Sigrid Juselius Foundation (to E.R.K. and E.L.), the Institute Pasteur-Fondazione Cenci Bolognetti (to M.R.), the Austrian Federal Government (W.S.), the Medical University Vienna (W.S.) and a Wellcome Trust Programme Grant (to M.F.).

Author information

Author notes

    • Peer Wulff
    • , Thomas Goetz
    •  & William Wisden

    Present address: Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.

    • Peer Wulff
    •  & Thomas Goetz

    These authors contributed equally to this work.

Affiliations

  1. Department of Clinical Neurobiology, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.

    • Peer Wulff
    • , Thomas Goetz
    •  & William Wisden
  2. Institute of Biomedicine, Pharmacology, Biomedicum Helsinki, POB 63 (Haartmaninkatu 8), University of Helsinki, FI-00014 Helsinki, Finland.

    • Elli Leppä
    • , Anni-Maija Linden
    • , Olga Y Vekovischeva
    •  & Esa R Korpi
  3. Department of Pharmacology, University College London, Gower Street, London WC1E 6BT, UK.

    • Massimiliano Renzi
    •  & Mark Farrant
  4. MRC Anatomical Neuropharmacology Unit, Oxford University, Mansfield Road, Oxford OX1 3TH, UK.

    • Jerome D Swinny
    •  & Peter Somogyi
  5. Center for Brain Research, Section of Biochemistry and Molecular Biology of the Nervous System, Medical University of Vienna, Spitalgasse 4, A-1090 Vienna, Austria.

    • Werner Sieghart

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Contributions

The original idea was conceived by W.S. and developed with P.S., W.W. and E.R.K. Experiments were designed by M.F., E.R.K., P.S., P.W., W.S. and W.W. Experiments were performed by M.F., T.G., A.-M.L., E.L., M.R., J.D.S., P.S., O.Y.V., P.W. and W.W. Behavioral data were analyzed by E.L., A.-M.L. and E.R.K. Electrophysiological data were analyzed by M.F. The manuscript was written by M.F., P.W. and W.W. All authors commented on and helped to revise the text.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Peer Wulff.

Supplementary information

PDF files

  1. 1.

    Supplementary Fig. 1

    Generation of γ2I77lox and L7γ2F77GFP mice.

  2. 2.

    Supplementary Fig. 2

    Confirmation of Purkinje cell–specific Cre activity in the L7Cre line using ROSA26 indicator mice.

  3. 3.

    Supplementary Fig. 3

    Expression of the γ2F77GFP subunit in cerebellar Purkinje cells of PC-γ2–swap mice.

  4. 4.

    Supplementary Fig. 4

    In slices from PC-γ2–swap mice, potentiation of GABAA receptor–mediated mIPSCs by zolpidem is restricted to Purkinje cells.

  5. 5.

    Supplementary Methods

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DOI

https://doi.org/10.1038/nn1927

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