Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Possible New Cell Type Found in Developing Inner Ear

12.06.2003


Dr. Paul Sohal



The answer to how the complex, cavernous inner ear forms from a mostly homogenous group of cells may be that it doesn’t, says a Medical College of Georgia researcher who has found a new cell type that appears to migrate to the developing ear.

Dr. Paul Sohal first saw the cells he named ventrally emigrating neural tube cells in 1995, following the path of newly formed nerves out of the developing neural tube.

His research published in the June issue of the International Journal of Developmental Neuroscience says one place VENT cells go is to the developing inner ear.



“One thing which has been a puzzle was how can a single source of cells gives rise to entirely different systems, functionally different systems,” Dr. Sohal, developmental biologist, says of the inner ear which is believed to be formed from the same cells that form the outer layer of skin or epidermis. The only other cell believed to be in the region is the pigment-producing melanocyte.

By day two of development in the chick embryo, Dr. Sohal’s animal model, the neural tube -- a tubular structure that gives rise to the brain and spinal cord -- has formed and is covered with a skin called the surface ectoderm. That same day, an area of the skin on either side and about midway down the neural tube begins to thicken into what is known as an auditory placode. This thickened area begins to move inward, eventually working free from surrounding tissue and, by day three, forms the otic vesicle that will become the inner ear. In humans this should happen in the second month of development.

“What we have found is that, at this stage, VENT cells begin to move in from the neural tube and mix with these cells,” Dr. Sohal says. He believes VENT cells provide a heterogeneous mix to the epidermal cells, which could help explain the ability of cells within the region to form so many different types of tissue.

The developed inner ear is a complex structure that enables hearing and balance. The visible outer ear focuses sound to the middle then inner ear, which contain the eardrum and three bones that convert sound energy into mechanical energy. The movement of the bones applies pressure to the cochlea, a snail-shaped, fluid-filled organ, converting sound to a stimulus that triggers the hair cells. The hair cells -- which can be lost to disease, trauma or a congenital defect -- are activated and send signals to the nerve and eventually the brain where sound is perceived.

Dr. Sohal has published studies that show VENT cells in many areas of the body, most recently in the heart, small intestines and stomach. Still, he is meeting with resistance from some fellow scientists who are skeptical that he has found the first new cell type to be identified in the embryo since 1868. Some say the cells are simply experimental artifacts.

He believes they are much more, that the cells not only can form the four major types of body tissue but that they are the source of stem cells.

“The data is intriguing,” says Dr. David J. Kozlowski, developmental geneticist at MCG who is studying hair cell regeneration within the zebrafish inner ear to try to understand how hair cells regenerate in fish and not mammals.

Dr. Kozlowski, who also directs MCG’s Transgenic Zebrafish Core Facility, is looking for VENT cells in the zebrafish, another developmental model, to see if he can document their existence. “It’s certainly worth investing some effort to see if they exist in fish and, if they do, where do they go,” he says.

Dr. Sohal, undaunted most days, says the ubiquitous cells go pretty much everywhere, at least everywhere he has looked to date. “I think this tells us they are a general phenomenon, that the cells have a fundamental role.”

Back inside the ear, Dr. Sohal is now looking to determine if VENT cells are part of functional units within the inner ear. “What we have to do is find out where they end up. Are they part of the cochlea? Are they part of the sensory organs?” he says.

His work is funded by the National Institutes of Health.

Toni Baker | Medical College of Georgia
Further information:
http://www.mcg.edu/news/2003NewsRel/Sohal.html

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>