The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-dependent protein kinase (PKA)- and ATP-regulated chloride channel whose activity determines the rate of electrolyte and fluid transport in a variety of epithelial tissues. Dysfunctional CFTR activity is involved in the pathogenesis of diseases including cystic fibrosis (CF), secretory diarrhea and pancreatitis. CFTR is expressed in the apical membrane of epithelial cells in tissues affected in these diseases, where its activity contributes to the transport of transepithelial salt and fluid. CFTR is thus directly involved in the pathology of at least two major diseases that cause morbidity and mortality in millions of individuals throughout the world. However, the molecular mechanisms that modulate CFTR activity in epithelial tissues are poorly understood. The development of effective treatments for these diseases would be facilitated by detailed knowledge of various cellular factors that regulate the activity of CFTR. In addition, recent evidences suggest that CFTR may exist in macromolecular complexes, in which protein-protein interactions may influence its Cl- channel activity. Identification of proteins that interact with CFTR might provide important insights into various cellular mechanisms involving CFTR. Our laboratory has isolated a number of proteins that bind to CFTR. One such protein NHERF causes a pronounced increase in CFTR channel activity. Since CF is caused by insufficient CFTR activity at the plasma membrane, a detailed understanding of CFTR?NHERF interaction could yield important clinical benefits, including possible therapeutic strategies for CF. A major goal of our laboratory is to elucidate the molecular mechanisms involved in the regulation of CFTR channel activity with a view to provide crucial insights leading to a more effective treatment for cystic fibrosis.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Intramural Research (Z01)
Project #
1Z01HL001286-01
Application #
6966900
Study Section
(LKEM)
Project Start
Project End
Budget Start
Budget End
Support Year
1
Fiscal Year
2004
Total Cost
Indirect Cost
Name
U.S. National Heart Lung and Blood Inst
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Beck, Edward J; Yang, Yu; Yaemsiri, Sirin et al. (2008) Conformational changes in a pore-lining helix coupled to cystic fibrosis transmembrane conductance regulator channel gating. J Biol Chem 283:4957-66
Liedtke, Carole M; Raghuram, Viswanathan; Yun, C Chris et al. (2004) Role of a PDZ1 domain of NHERF1 in the binding of airway epithelial RACK1 to NHERF1. Am J Physiol Cell Physiol 286:C1037-44
Yoo, Dana; Flagg, Thomas P; Olsen, Olav et al. (2004) Assembly and trafficking of a multiprotein ROMK (Kir 1.1) channel complex by PDZ interactions. J Biol Chem 279:6863-73