Characterization of CFTR chloride channel
Date of Issue2009
School of Biological Sciences
Cystic fibrosis (CF) is an inherited disease caused by mutations in a single gene which encodes the cystic fibrosis transmembrane conductance regulator (CFTR), a member of ATP-binding cassette (ABC) proteins superfamily. Since the genetic basis of CF was resolved in 1989 when the CFTR gene was cloned and disease-associated mutations were identified, remarkable progress have been made in understanding CF and CFTR. However, there is no cure for CF or effective control of the destruction of the lungs and pancreas of CF patients. What’s more, despite the progress in elucidating domains involved in CFTR channels function, the structure basis for chloride conductance through CFTR remains incompletely understood. For example, the possible interactions among the CFTR proteins have not been demonstrated at the cell membranes if they can form a dimer or an oligomer. Therefore, we tested whether CFTR is monomeric or oligomeric by analyzing the population of channel conductance from cells co-expressing two mutants with different single channel properties. And our results suggest that CFTR channel pore is made up from a monomer. However, our findings also provide direct functional evidence supporting the notion that CFTR can exist as dimer or even multimer in the cell membranes.