Tol2-Mediated Gene Transfer and In Ovo Electroporation of the Otic Placode: A Powerful and Versatile Approach for Investigating Embryonic Development and Regeneration of the Chicken Inner Ear

  • Stephen Freeman
  • Elena Chrysostomou
  • Koichi Kawakami
  • Yoshiko Takahashi
  • Nicolas Daudet
Part of the Methods in Molecular Biology book series (MIMB, volume 916)


The vertebrate inner ear is composed of several specialized epithelia containing mechanosensory “hair” cells, sensitive to sound and head movements. In mammals, the loss of hair cells for example during aging or after noise trauma is irreversible and results in permanent sensory deficits. By contrast, avian, fish, and amphibians can efficiently regenerate lost hair cells following trauma. The chicken inner ear is a classic model system to investigate the cellular and molecular mechanisms of inner ear development and regeneration, yet it suffered until recently from a relative lack of flexible tools for genetic studies. With the introduction of in ovo electroporation and of Tol2 transposon vectors for gene transfer in avian cells, the field of experimental possibilities has now expanded significantly in this model. Here we provide a general protocol for in ovo electroporation of the chicken otic placode and illustrate how this approach, combined with Tol2 vectors, can be used to drive long-term and inducible gene expression in the embryonic chicken inner ear. This method will be particularly useful to investigate the function of candidate genes regulating progenitor cell behavior and sensory cell differentiation in the inner ear.

Key words

Inner ear Otic placode Hair cell Chicken embryo Electroporation Transfection Tol2 transposon Development Regeneration 



N.D. thanks Dr. Alexander Davies for teaching him the basics of in ovo electroporation. This work was supported by Deafness Research UK and the Biotechnology and Biological Sciences Research Council (BBSRC).


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Stephen Freeman
    • 1
  • Elena Chrysostomou
    • 1
  • Koichi Kawakami
    • 2
  • Yoshiko Takahashi
    • 3
  • Nicolas Daudet
    • 1
  1. 1.UCL Ear InstituteUniversity College LondonLondonUK
  2. 2.Division of Molecular and Developmental BiologyNational Institute of GeneticsMishimaJapan
  3. 3.Graduate School of Biological SciencesNara Institute of Science and Technology (NAIST)IkomaJapan

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