Cells (Oct 2022)

The Effect of a <i>Pex3</i> Mutation on Hearing and Lipid Content of the Inner Ear

  • Rafael M. Kochaj,
  • Elisa Martelletti,
  • Neil J. Ingham,
  • Annalisa Buniello,
  • Bebiana C. Sousa,
  • Michael J. O. Wakelam,
  • Andrea F. Lopez-Clavijo,
  • Karen P. Steel

Journal volume & issue
Vol. 11, no. 20
p. 3206


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Peroxisome biogenesis disorders (due to PEX gene mutations) are associated with symptoms that range in severity and can lead to early childhood death, but a common feature is hearing impairment. In this study, mice carrying Pex3 mutations were found to show normal auditory development followed by an early-onset progressive increase in auditory response thresholds. The only structural defect detected in the cochlea at four weeks old was the disruption of synapses below inner hair cells. A conditional approach was used to establish that Pex3 expression is required locally within the cochlea for normal hearing, rather than hearing loss being due to systemic effects. A lipidomics analysis of the inner ear revealed a local reduction in plasmalogens in the Pex3 mouse mutants, comparable to the systemic plasmalogen reduction reported in human peroxisome biogenesis disorders. Thus, mice with Pex3 mutations may be a useful tool to understand the physiological basis of peroxisome biogenesis disorders.