In a paper that will appear in an upcoming issue of the journal Nature, the team reports that a protein called cadherin 23 is part of a complex of proteins called "tip links" that are on hair cells in the inner ear. These hair cells are involved in the physiological process called mechanotransduction, a phenomenon in hearing in which physical cues (sound waves) are transduced into electrochemical signals and communicated to the brain. The tip link is believed to have a central function in the conversion of physical cues into electrochemical signals.
"In humans, there are mutations in [the gene] cadherin 23 that cause deafness as well as Usher syndrome, the leading cause of deaf-blindness," says Associate Professor Ulrich Mueller, Ph.D., who is in the Department of Cell Biology at The Scripps Research Institute and is a member of Scripps Research's Institute for Childhood and Neglected Diseases.
A parallel study led by Mueller's collaborator Teresa Nicolson, Ph.D., and her colleagues at the Oregon Hearing Research Center and Vollum Institute corroborated Mueller's results by showing that when the cadherin 23 gene is deleted in mutant zebrafish, tip links never form.
Both studies explain how the cadherin 23 gene is a direct cause of certain types of deafness and suggest a potential therapeutic target for treating deafness.
The Physiology of Hearing and Deafness
Childhood and age-related hearing impairment is a major issue in our society. According to the National Institute on Deafness an Other Communication Disorders, one in t
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Contact: Jason Bardi
jasonb@scripps.edu
858-784-9254
Scripps Research Institute
28-Mar-2004