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Updated: Sep 21, 2026

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae
Published on: March 10, 2012
Cl(-)-dependent HCO3- transport by cystic fibrosis transmembrane conductance regulator
1Department of Physiology, UT Southwestern Medical Center, Dallas, TX 75235-9040, USA. smuall@mednet.swmed.edu
Abstract:
Cystic fibrosis (CF) affects the function of multiple organs. The inability to maintain luminal hydration of ducts leads to their plugging and destruction of the affected organs. An exacerbating problem is the acidic pH of the fluid produced by CF patients' secretory glands. This is best documented for pancreatic secretion. Alkaline fluid secretion requires vectorial transport of electrolytes and of HCO(3)(-). The mechanism of HCO(3)(-) secretion by cystic fibrosis transmembrane conductance regulator (CFTR) expressing cells is not well understood. In the present communication we discuss results suggesting that CFTR itself can transport large amounts of HCO(3)(-) and that HCO(3)(-) transport by CFTR is mediated by a coupled, Cl(-)-dependent process that is different from a simple HCO(3)(-) conductance.
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