Transmembrane conductance

Cystic fibrosis Cystic fibrosis transmembrane conductance regulator (CFTR) Benzo(c)quinolizinium derivatives, VRT-325... 

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), a chloride (CF) channel characterised by chloride permeability and secretion, and also by the regulation of other epithelial ion channels (Eidelman et al, 2001). Mutations in the CFTR gene lead to an impaired or absent Cl conductance in the epithelial apical membrane, which leads to defective Cl secretion and absorption across the epithelium. Genistein (Illek et al, 1995 Weinreich et al, 1997) and other flavonoids (Illek and Fisher, 1998) have been shown, in different animal and tissue models, to activate wild-type CFTR and CFTR mutants by (Eidelman et al, 2001 Roomans, 2001 Suaud et al, 2002) ... 

Cystic fibrosis transmembrane conductance exporter family... 

A novel class of activators for chloride conductance in the cystic fibrosis transmembrane conductance regulator protein has been identified. These 3-(2-benzy-loxyphenyl)isoxazoles and 3-(2-benzyloxyphenyl)isoxazolines have been synthesized employing the 1,3-dipolar cycloaddition of nitrile oxides with various alkene and alkyne dipolarophiles (490). 

CFTR Cystic fibrosis transmembrane conductance regulator... 

Wagner, J. A., T. V. McDonald, P. T. Nghiem, A. W. Lowe, H. Schulman, D. C. Gruenert, L. Stryer, and P. Gardner. 1992. Antisense oligodeoxynucleotides to the cystic fibrosis transmembrane conductance regulator inhibit cAMP-activated but not calcium-activated chloride currents. Proc Natl Acad Sci USA 89(15) 6785-9. 

CF is caused by the absence of a protein called cystic fibrosis transmembrane conductance regulator (CFTR). This protein is required for the transport of chloride ions across cell membranes. On the molecular level, there is a mutation in the gene that encodes for CFTR. As a result, CFTR cannot be processed properly by the cell and is unable to reach the exocrine glands to assume its transport function. 

Cheung M, Akabas MH. 1996. Identification of the cystic fibrosis transmembrane conductance regulator channellining residues in and flanking the M6 membrane-spanning segment. Biophys J 70 2688-2695. 

CFTR (cystic fibrosis transmembrane conductance regulator) a membrane protein that functions as a chloride channel. 

Sato S, Ward CL, Kopito RR (1998) Cotranslational ubiquitination of cystic fibrosis transmembrane conductance regiilator in vitro. J Biol Chem 273 7189-7192 Schatz G, Dobberstein B (1996) Common principles of protein translocation across membranes. Science 271 1519-1526... 

Ward CL, Kopito RR (1994) Intracellular turnover of cystic fibrosis transmembrane conductance regulator Ineffident processing and rapid degradation of wild-type and mutant proteins.) Biol Chem 269 25710-25718 Ward CL, Omura S, Kopito RR (1995) Degradation of CFTR by the ubiquitin-proteasome pathway. Cell 83 121-127... 

Xiong X, Chong E, Skach W R (1999) Evidence that endoplasmic reticulum (ER)-assodated degradation of cystic fibrosis transmembrane conductance regulator is linked to retrograde translocation from the ER membrane. J Biol Chem 274 2616-2624... 

The gene product is termed CFTR (cystic fibrosis transmembrane conductance regulator), and it codes for a chloride ion channel. It may also carry out additional (as yet undetermined) functions. 

The cystic fibrosis (c/) gene was first identified in 1989. It codes for a 170 kDa protein, the cystic fibrosis transmembrane conductance regulator (CFTR), which serves as a chloride channel in epithelial cells. Inheritance of a mutant cftr gene from both parents results in the CF phenotype. While various organs are affected, the most severely affected are the respiratory epithelial cells, which have, unsurprisingly, become the focus of attempts at corrective gene therapy. 

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