Navigation Links
The cellular intricacies of cystic fibrosis
Date:9/19/2011

Bethesda, Md. (Sept. 19, 2011) 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.

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."


'/>"/>

Contact: Donna Krupa
dkrupa@the-aps.org
301-634-7209
American Physiological Society
Source:Eurekalert

Related biology news :

1. Cellular metabolism self-adapts to protect against free radicals
2. New cellular surprise may help scientists better understand human mitochondrial diseases
3. Cellular laser microsurgery illuminates research in vertebrate biology
4. Cellular stress can induce yeast to promote prion formation
5. Researchers provide means of monitoring cellular interactions
6. Development of a FRET sensor for real-time imaging of intracellular redox dynamics
7. How muscle develops: A dance of cellular skeletons
8. Harvard scientists see the early cellular cause of dry eye disease for the first time
9. Thalidomide shows efficacy as adjuvant therapy for hepatocellular carcinoma patients
10. WSU proves extracellular matrix tugging creates come hither stimulus for cancer migration
11. Extracting cellular engines may aid in understanding mitochondrial diseases
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/20/2016)... , June 20, 2016 Securus Technologies, ... technology solutions for public safety, investigation, corrections and ... prisons involved, it has secured the final acceptance ... facilities for Managed Access Systems (MAS) installed. Furthermore, ... facilities to be installed by October, 2016. MAS ...
(Date:6/15/2016)... ALBANY, New York , June 15, 2016 ... published a new market report titled "Gesture Recognition Market ... Trends and Forecast, 2016 - 2024". According to the ... at USD 11.60 billion in 2015 and is ... and reach USD 48.56 billion by 2024.  ...
(Date:6/9/2016)... -- Paris Police Prefecture ... to ensure the safety of people and operations in several ... tournament Teleste, an international technology group specialised in ... that its video security solution will be utilised by ... safety across the country. The system roll-out is scheduled for ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... WI (PRWEB) , ... June 23, 2016 , ... ... supplements, is pleased to announce the launch of their brand, UP4™ Probiotics, into ... for over 35 years, is proud to add Target to its list of ...
(Date:6/23/2016)... -- Houston Methodist Willowbrook Hospital has signed a ... serve as their official health care provider. As ... provide sponsorship support, athletic training services, and most ... athletes and families. "We are excited ... to bring Houston Methodist quality services and programs ...
(Date:6/23/2016)... SAN FRANCISCO , June 23, 2016   ... it has secured $1 million in debt financing from ... to ramp up automation and to advance its drug ... for its new facility. "SVB has been ... goes beyond the services a traditional bank would provide," ...
(Date:6/23/2016)... Ky. , June 23, 2016 ... two Phase 1 clinical trials of its complement ... placebo-controlled, single and multiple ascending dose studies designed ... pharmacodynamics (PD) of subcutaneous injection in healthy adult ... subcutaneously (SC) either as a single dose (ranging ...
Breaking Biology Technology: