ATP-binding cassette domain of the cystic fibrosis transmembrane regulator, subfamily C
The CFTR subfamily domain 1. The cystic fibrosis transmembrane regulator (CFTR), the product of the gene mutated in patients with cystic fibrosis, has adapted the ABC transporter structural motif to form a tightly regulated anion channel at the apical surface of many epithelia. Use of the term assembly of a functional ion channel implies the coming together of subunits, or at least smaller not-yet functional components of the active whole. In fact, on the basis of current knowledge only the CFTR polypeptide itself is required to form an ATP- and protein kinase A-dependent low-conductance chloride channel of the type present in the apical membrane of many epithelial cells. CFTR displays the typical organization (IM-ABC)2 and carries a characteristic hydrophilic R-domain that separates IM1-ABC1 from IM2-ABC2.
Jiyao W et al.(2023). "The conserved domain database in 2023.",