Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers unravel a central mystery of how hearing happens

14.10.2004


Scientists at the University of Virginia Health System have helped solve the mystery of how the human ear converts sound vibrations and balance stimuli into electrical impulses the brain can interpret. Their research is detailed in the October 13 advance online edition of the journal Nature, found at www.nature.com/nature .

Neuroscience researchers Jeffrey Holt and Gwenaëlle Géléoc, working in collaboration with scientists elsewhere, discovered a long-sought protein called TRPA1 that is located at the tips of the tiny sensory cells in the inner ear. They found that TRPA1 converts sound into nerve impulses, which are transmitted to the brain. Identification of the protein and the gene that encodes TRPA1, could allow for future treatments for deafness. "This is one of the most significant findings in sensory biology, detailing an ingeniously simple, but remarkably sensitive system," said Holt, an assistant professor of neuroscience and otolaryngology at the U.Va. Health System.

"For hearing researchers, this discovery is the holy grail in understanding the function of both hearing and balance," said Jeffrey Corwin, professor of neuroscience at U.Va. The protein TRPA1 works by forming a channel resembling a donut in the cell membrane of inner ear hair cells. "In the absence of sound, the hole is closed, "Holt explained. "But when sound strikes the protein, the hole pops open like a trap door, allowing potassium and calcium ions to flood into the cells. Because these elements carry a positive charge, an electrical signal is generated which is relayed to the brain for interpretation."



Now that this genetic link to hearing has been established, Holt said, geneticists can examine the gene that encodes TRPA1 in deaf patients, some of whom he expects may have a mutated form of the TRPA1 gene. "This could allow for the development of new gene therapies for deafness and balance disorders in the next five to ten years," Holt said. "Essentially, if we could take a correct copy of the gene and reintroduce it into the cells of the inner ear, we might be able to restore hearing and balance function in people with hereditary inner ear disorders."

A large body of circumstantial evidence has accumulated over the past 25 years that suggests a mechanically sensitive, donut-shaped protein must be at the heart of the body’s hearing apparatus, but scientists had no idea of what it was, despite intense effort. Holt and Géléoc previously identified an 18-hour window for the functional development of inner ear hair cells in mouse embryos. This breakthrough helped them identify that the TRPA1 gene was turned on during the same 18-hour period, sending the U.Va. scientists down the path to discovery.

"Now that we’ve identified TRPA1 as the hair cell transduction channel," Géléoc said, "this opens a window of opportunity with significant implications for the field of hearing and deafness research and beyond, including the fields of engineering and nanotechnology."

The husband and wife team of Holt and Géléoc, an assistant professor of research in neuroscience and otolaryngology at U.Va., worked in collaboration with scientists at Northwestern University, Duke University, Harvard Medical School and the National Institutes of Health. "This represents science at its best," Holt said. "We approached this question from a number of angles, with a number of different techniques and in a number of different research labs. The fact that we collaborated and came up with the same answer independently allows us to make a much more convincing scientific argument than any one scientist or lab could have done on their own."

Bob Beard | EurekAlert!
Further information:
http://www.virginia.edu
http://www.nature.com/nature

More articles from Life Sciences:

nachricht Enduring cold temperatures alters fat cell epigenetics
19.04.2018 | University of Tokyo

nachricht Full of hot air and proud of it
18.04.2018 | University of Pittsburgh

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

Im Focus: The Future of Ultrafast Solid-State Physics

In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.

Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Diamond-like carbon is formed differently to what was believed -- machine learning enables development of new model

19.04.2018 | Materials Sciences

Electromagnetic wizardry: Wireless power transfer enhanced by backward signal

19.04.2018 | Physics and Astronomy

Ultrafast electron oscillation and dephasing monitored by attosecond light source

19.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>