Featured Research

from universities, journals, and other organizations

Scientist studies frogs and fish for answers to human hearing

Date:
March 18, 2011
Source:
House Ear Institute
Summary:
Scientists are exploring the molecules and tissues necessary for normal inner ear development in two different species that are model organisms for developmental biological studies: the African clawed frog and the zebrafish.

Andres Collazo, Ph.D., looks at zebrafish which he studies at the molecular level to better understand the embryonic development of human hearing.
Credit: House Ear Institute

Scientists in the House Ear Institute laboratory of Andres Collazo, Ph.D., study inner ear development. Their work explores the molecules and tissues necessary for normal inner ear development in two different species that are model organisms for developmental biological studies: the African clawed frog Xenopus laevis and the zebrafish Danio rerio.

Why study frogs and fish? These are excellent subjects for study because during embryonic stages of development, the hearing and balance organs of both species greatly resemble those of humans. In addition, genomic sequencing of frogs and zebrafish has revealed that both species share the majority of the genes found in humans. By studying frogs and fish, whose eggs are fertilized and develop outside the mother, the scientists can address their hypotheses in living intact embryos.

Our inner ear develops in the embryo from a simple flap of skin called the otic placode into a complex, three dimensional structure that enables balance and hearing. The goal of Dr. Collazo's zebrafish research is to understand at the molecular level, how and why otic placode cells decide to become neuronal, nonsensory or sensory cells.

"Zebrafish provide a powerful, easily maniplulated genetic system for understanding the role of specific molecules during development," said Andres Collazo, Ph.D., House Ear Institute.

The main goal of the frog research is to determine which molecules and regions of the otic placode are required for normal patterning in the developing inner ear. These studies provide a better understanding of the causes of human inner ear malformations. Working with a team of scientists, Dr. Collazo, has discovered that physically removing either the front or back half of the otic placode in the Xenopus frog, results in a high percentage of mirror image duplicated inner ears. Mirror duplications generate a specific pattern in the wrong place, which helps in identifying which molecules are required for the normal layout of the inner ear. These studies also provide insights into some of the inner ear malformations seen in clinical patients.

Proper patterning, positioning and differentiation of the sensory organs within the inner ear are crucial for normal function in balance and hearing. Studies have found that the gene mutations in zebrafish, which can result in mirror duplicated inner ears, are found in molecules belonging to the cell signaling pathway designated Shh. Similarly, blocking the cell signaling pathway designated as Hh in the Xenopus frog or in zebrafish, results in two mirror image front halves and suggests that Shh signaling is necessary for patterning the back half. This is important because any future therapies developed for replacing lost sensory cells (hair cells) that detect motion in the inner ear, will require that the regenerated hair cells be accurately placed and positioned.


Story Source:

The above story is based on materials provided by House Ear Institute. Note: Materials may be edited for content and length.


Cite This Page:

House Ear Institute. "Scientist studies frogs and fish for answers to human hearing." ScienceDaily. ScienceDaily, 18 March 2011. <www.sciencedaily.com/releases/2011/03/110318204805.htm>.
House Ear Institute. (2011, March 18). Scientist studies frogs and fish for answers to human hearing. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2011/03/110318204805.htm
House Ear Institute. "Scientist studies frogs and fish for answers to human hearing." ScienceDaily. www.sciencedaily.com/releases/2011/03/110318204805.htm (accessed April 24, 2014).

Share This



More Health & Medicine News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins