AUG 04, 2019 4:41 PM PDT

New Research In Reversing Deafness

WRITTEN BY: Amanda Mikyska

Hair cells inside the human ear are responsible for sensing and relaying sound to the brain.  In all mammals except humans, these cells can regenerate if damaged.  In humans, when a hair cell dies because of damage from loud noises, a virus, or genetic mutation, the loss is permanent.    

Scientists at Johns Hopkins University are now investigating the molecular signaling pathways of hair cell differentiation and growth, to find a way to regenerate damaged hair cells.  This would help people with deafness regain hearing, regardless of the cause.

Undamaged cochlear hair cells vs. damaged cochlear hair cells.

 

Previously, scientist knew about two genes, HEY1 and HEY2, which repress the differentiation of precursor hair cells into functional hair cells.  Without the HEY1 and HEY2 genes, cells prematurally differentiate and do not fully grow.  Interestingly, the expression of these two genes also expresses small amounts of "inhibitor of differentiation" (ID) proteins.  An accumulation of ID proteins, however, interfere with the ability of repressors to bind to the DNA.  When the repressor proteins cannot bind to DNA, the cells differentiate into audio-sensing hair cells, in an organized spiral.  The slow accumulation of ID proteins is a biological timer that results in the precise birth of audio-sensing cells.  

Most recently, scientists at Johns Hopkins University found that the proteins responsible for balancing the timing of differentiation are Activin A, a member of the cytokinin family, and  Follistatin (FST).  Precursor hair cells grow from the outside of the cochlear spiral to the inside.  Along the way, FST is expressed and represses differentiation of these precursor hair cells.  Activin A signals differentiation and is expressed in the reverse direction, beginning with cells at the center of the cochlear spiral.   

At the moment, there is no way to engineer hair cells to regenerate.  However, with more research on the underlying molecular controls, a therapy for hearing loss draws closer.   
 

 

Sources: Prajapati-DiNubila

About the Author
  • Amanda graduated from the University of Massachusetts Boston with a degree in Biology. After working in research on creating biochemicals from genetically engineered yeast, she started freelance science writing while traveling the world. Now, Amanda is a Lab Manager and Research Assistant at the the University of Central Florida, studying the molecular phylogeny of parasitic wasps. She writes about the latest research in Neuroscience, Genetics & Genomics, and Immunology. Interested in working on solutions for food/water security, sustainable fuel, and sustainable farming. Amanda is an avid skier, podcast listener, and has run two triathlons.
You May Also Like
AUG 31, 2021
Clinical & Molecular DX
Five Questions to Help You Select the Best Cellular Stain
AUG 31, 2021
Five Questions to Help You Select the Best Cellular Stain
Cellular stains are organic fluorescent dyes or fluorescent conjugates designed to localize to a specific organelle or c ...
SEP 14, 2021
Immunology
The Spleen Creates Long-Lasting Protection Against the Flu Virus
SEP 14, 2021
The Spleen Creates Long-Lasting Protection Against the Flu Virus
You share an elevator with an individual who is coughing and sneezing, only to find yourself feeling unwell a few days l ...
SEP 26, 2021
Coronavirus
LIBRA-Seq ID's a Potent Antibody to Fight COVID-19
SEP 26, 2021
LIBRA-Seq ID's a Potent Antibody to Fight COVID-19
Humans can produce millions or even billions of antibodies, so only so many can be captured and screened. But those anti ...
OCT 12, 2021
Immunology
Major Landmark in a 100-Year Search for a Malaria Vaccine
OCT 12, 2021
Major Landmark in a 100-Year Search for a Malaria Vaccine
In one of the greatest global health milestones of our time, the World Health Organization has approved the widespread d ...
OCT 17, 2021
Cardiology
Flu Vaccination Significantly Reduces Risk of Cardiac Events
OCT 17, 2021
Flu Vaccination Significantly Reduces Risk of Cardiac Events
The flu has been associated with a significantly increased risk of a cardiac event like heart attack or stroke.
NOV 18, 2021
Immunology
Could Maternal Antibodies Contribute to Autism Development?
NOV 18, 2021
Could Maternal Antibodies Contribute to Autism Development?
Pregnant mothers pass on oxygen and nutrients to their developing babies while shuttling away waste products from the fe ...
Loading Comments...