Featured Research

from universities, journals, and other organizations

Cellular intricacies of cystic fibrosis

Date:
September 19, 2011
Source:
American Physiological Society
Summary:
When researchers discovered the primary genetic defect that causes cystic fibrosis (CF) back in 1989, they opened up a new realm of research into treatment and a cure for the disease. Since then, scientists have been able to clone the defective gene and study its effects in animals. Now researchers have developed a technique for observing the defects at work in human tissue donated by patients with CF.

When researchers discovered the primary genetic defect that causes cystic fibrosis (CF) back in 1989, they opened up a new realm of research into treatment and a cure for the disease. Since then, scientists have been able to clone the defective gene and study its effects in animals. Now researchers at the University of North Carolina at Chapel Hill have developed a technique for observing the defects at work in human tissue donated by patients with CF.

Related Articles


This technique has yielded an extraordinary view of the cellular intricacies of CF, which Martina Gentzsch, assistant professor of cell and developmental biology, will discuss at the 7th International Symposium on Aldosterone and the ENaC/Degenerin Family of Ion Channels, being held September 18-22 in Pacific Grove, Calif. The meeting is sponsored by the American Physiological Society. Her poster presentation is entitled, "The Cystic Fibrosis Transmembrane Conductance Regulator Inhibits Proteolytic Stimulation of ENaC."

Ion Transport Processes in CF

Cystic fibrosis is caused by a mutation in the gene that encodes a protein called cystic fibrosis transmembrane conductance regulator (CFTR), which functions as a chloride channel at the surface of airways and moves chloride out of the cells. CFTR also regulates another protein called epithelial sodium channel (ENaC), which is responsible for transporting sodium into cells. Thus far, scientists have been able to establish that when the CFTR mutation is present, ENaC becomes overactive and causes the cells in the lungs to absorb too much sodium. Water follows the sodium from the cells' surfaces into the cells, and as a result, the airways become dry and mucous becomes thick and sticky, leading to infections in the lungs.

To observe how CFTR regulates ENaC, Dr. Gentzsch and her team took cells from healthy lung tissue and CF lung tissue and maintained them in a liquid medium. The cells' surfaces were exposed to air, which prompted the cells to grow and behave as though they were still inside human lungs. Then the team studied proteolytic cleavage of ENaC, a process in which the ENaC protein is cut by enzymes called proteases at specific sites on the protein. This limited cleavage causes ENaC to become active. When the team analyzed the cells' behavior, they found that ENaC was more likely to have undergone cleavage in cells from CF tissue.

According to Dr. Gentzsch, these observations prompted two questions. First, what role does CFTR play in regulating ENaC cleavage? Second, why is ENaC cleavage not regulated in CF?

"CFTR binds to ENaC, so our initial thought was that close contact of ENaC to CFTR protects ENaC from being cleaved. But another possibility is that CFTR is responsible for suppressing ENaC cleavage and activation," said Dr. Gentzsch. In other words, the absence of a normally functioning CFTR protein may cause ENaC overactivity. Because there is more cleavage when the CFTR mutation is present, it implies that healthy CFTR prevents ENaC cleavage and activation, but defective CFTR does not.

Either way, Dr. Gentzsch feels that both CFTR and ENaC should be considered when developing therapies for CF. "Successful treatments should address both decreased CFTR function and increased salt absorption caused by ENaC overactivity."


Story Source:

The above story is based on materials provided by American Physiological Society. Note: Materials may be edited for content and length.


Cite This Page:

American Physiological Society. "Cellular intricacies of cystic fibrosis." ScienceDaily. ScienceDaily, 19 September 2011. <www.sciencedaily.com/releases/2011/09/110919104805.htm>.
American Physiological Society. (2011, September 19). Cellular intricacies of cystic fibrosis. ScienceDaily. Retrieved March 4, 2015 from www.sciencedaily.com/releases/2011/09/110919104805.htm
American Physiological Society. "Cellular intricacies of cystic fibrosis." ScienceDaily. www.sciencedaily.com/releases/2011/09/110919104805.htm (accessed March 4, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, March 4, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Adults Only Get The Flu Twice A Decade, Researchers Say

Adults Only Get The Flu Twice A Decade, Researchers Say

Newsy (Mar. 4, 2015) Researchers found adults only get the flu about once every five years. Scientists analyzed how a person&apos;s immunity builds up over time as well. Video provided by Newsy
Powered by NewsLook.com
New Hormone Could Protect Against Diabetes And Weight Gain

New Hormone Could Protect Against Diabetes And Weight Gain

Newsy (Mar. 4, 2015) A newly discovered hormone mimics the effects of exercise, protecting against diabetes and weight gain. Video provided by Newsy
Powered by NewsLook.com
Mount Everest Has a Poop Problem

Mount Everest Has a Poop Problem

Buzz60 (Mar. 4, 2015) With no bathrooms to use, climbers of Mount Everest have been leaving human waste on the mountain for years, and it&apos;s becoming a health issue. Mike Janela (@mikejanela) has more. Video provided by Buzz60
Powered by NewsLook.com
The Best Tips to 'Skinny' Your Home

The Best Tips to 'Skinny' Your Home

Buzz60 (Mar. 4, 2015) If you&apos;re looking to reach your health goals this season, there are a few simple tips to help you spring clean your space and improve your nutrition. Krystin Goodwin (@krystingoodwin) has the skinny on keeping a healthy home. Video provided by Buzz60
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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