The Murine Catecholamine Methyltransferase mTOMT is Essential for Mechanotransduction by Cochlear Hair Cells
- Johns Hopkins University, United States
- UCSD, United States
- Indiana University School of Medicine, United States
- TSRI, United States
Abstract
Hair cells of the cochlea are mechanosensors for the perception of sound. Mutations in the LRTOMT gene, which encodes a protein with homology to the catecholamine methyltransferase COMT that is linked to schizophrenia, cause deafness. Here we show that Tomt/Comt2, the murine ortholog of LRTOMT, has an unexpected function in the regulation of mechanotransduction by hair cells. The role of mTOMT in hair cells is independent of mTOMT methyltransferase function and mCOMT cannot substitute for mTOMT function. Instead, mTOMT binds to putative components of the mechanotransduction channel in hair cells and is essential for the transport of some of these components into the mechanically sensitive stereocilia of hair cells. Our studies thus suggest functional diversification between mCOMT and mTOMT, where mTOMT is critical for the assembly of the mechanotransduction machinery of hair cells. Defects in this process are likely mechanistically linked to deafness caused by mutations in LRTOMT/Tomt.
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Author details
Funding
National Institute on Deafness and Other Communication Disorders (5965)
- Ulrich Mueller
National Institute on Deafness and Other Communication Disorders (7704)
- Ulrich Mueller
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experiments were approved by the Institutional Animal Care and Use Committee at Johns Hopkins University School of Medicine (#M016M271).
Copyright
© 2017, Cunningham 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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The Murine Catecholamine Methyltransferase mTOMT is Essential for Mechanotransduction by Cochlear Hair Cells
eLife 6:e24318.
https://doi.org/10.7554/eLife.24318
Further reading
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