Manipulations of MeCP2 in glutamatergic neurons highlight their contributions to Rett and other neurological disorders

Abstract

Many postnatal onset neurological disorders such as autism spectrum disorders (ASDs) and intellectual disability are thought to arise largely from disruption of excitatory/inhibitory homeostasis. Although mouse models of Rett syndrome (RTT), a postnatal neurological disorder caused by loss-of-function mutations in MECP2, display impaired excitatory neurotransmission, the RTT phenotype can be largely reproduced in mice simply by removing MeCP2 from inhibitory GABAergic neurons. To determine what role excitatory signaling impairment might play in RTT pathogenesis, we generated conditional mouse models with Mecp2 either removed from or expressed solely in glutamatergic neurons. MeCP2 deficiency in glutamatergic neurons leads to early lethality, obesity, tremor, altered anxiety-like behaviors, and impaired acoustic startle response, which is distinct from the phenotype of mice lacking MeCP2 only in inhibitory neurons. These findings reveal a role for excitatory signaling impairment in specific neurobehavioral abnormalities shared by RTT and other postnatal neurological disorders.

Article and author information

Author details

  1. Xiangling Meng

    Department of Neuroscience, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  2. Wei Wang

    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
    Competing interests
    No competing interests declared.
  3. Hui Lu

    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
    Competing interests
    No competing interests declared.
  4. Ling-jie He

    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
    Competing interests
    No competing interests declared.
  5. Wu Chen

    Department of Neuroscience, Baylor College of Medicine, Houston, United States
    Competing interests
    No competing interests declared.
  6. Eugene Chao

    Department of Neuroscience, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  7. Marta L Fiorotto

    Children's Nutrition Research Center, Department of Pediatrics, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  8. Bin Tang

    Jan and Dan Duncan Neurological Research Institute, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  9. Jose A Herrera

    Jan and Dan Duncan Neurological Research Institute, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  10. Michelle L Seymour

    Huffington Center on Aging, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  11. Jeffrey L Neul

    Department of Neurosciences, UCSD, San Diego, United States
    Competing interests
    No competing interests declared.
  12. Frederick A Pereira

    Huffington Center on Aging, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  13. Jianrong Tang

    Department of Pediatrics, Baylor College of Medicine, Houston, United States
    Competing interests
    No competing interests declared.
  14. Mingshan Xue

    Department of Neuroscience, BCM, Houston, United States
    Competing interests
    No competing interests declared.
  15. Huda Y Zoghbi

    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, United States
    For correspondence
    hzoghbi@bcm.edu
    Competing interests
    Huda Y Zoghbi, Senior Editor, eLife.

Ethics

Animal experimentation: Mice were housed in an AAALAS-certified animal facility. All procedures to maintain and use these mice were approved by the Institutional Animal Care and Use committee for Baylor College of Medicine (Animal protocol number AN-1013 ).

Copyright

© 2016, Meng et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Xiangling Meng
  2. Wei Wang
  3. Hui Lu
  4. Ling-jie He
  5. Wu Chen
  6. Eugene Chao
  7. Marta L Fiorotto
  8. Bin Tang
  9. Jose A Herrera
  10. Michelle L Seymour
  11. Jeffrey L Neul
  12. Frederick A Pereira
  13. Jianrong Tang
  14. Mingshan Xue
  15. Huda Y Zoghbi
(2016)
Manipulations of MeCP2 in glutamatergic neurons highlight their contributions to Rett and other neurological disorders
eLife 5:e14199.
https://doi.org/10.7554/eLife.14199

Share this article

https://doi.org/10.7554/eLife.14199

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