High resolution

Module 3: Figure CFTR channel



Structure and function of the cystic fibrosis transmembrane conductance regulator (CFTR) channel.

The cystic fibrosis transmembrane conductance regulator (CFTR) channel is a single polypeptide that conducts anions, mainly Cl and HCO3. The channel opens when the nucleotide-binding domains 1 and 2 (NBD1, NBD2) undergo a conformational change when they bind ATP. The channels close when NBD2 hydrolyses ATP to ADP. This ATP-dependent switching between open and closed configurations depends upon the phosphorylation of a regulatory (R) domain by protein kinase A (PKA)