Changes in the R-region interactions depend on phosphorylation and contribute to PKA and PKC regulation of the cystic fibrosis transmembrane conductance regulator chloride channel.

The CFTR chloride channel is regulated by phosphorylation at PKA and PKC consensus sites within its regulatory region (R-region) through a mechanism, which is still not completely understood. We used a split-CFTR construct expressing the N-term-TMD1-NBD1 (Front Half; FH), TMD2-NBD2-C-Term (Back Half; BH), and the R-region as separate polypeptides (Split-R) in BHK cells, to investigate in situ how different phosphorylation conditions affect the R-region interactions with other parts of the protein. In proximity ligation assays, we studied the formation of complexes between the R-region and each half of the Split-CFTR.

ClC Channels and Transporters: Structure, Physiological Functions, and Implications in Human Chloride Channelopathies.

The discovery of ClC proteins at the beginning of the 1990s was important for the development of the Cl transport research field. ClCs form a large family of proteins that mediate voltage-dependent transport of Cl ions across cell membranes. They are expressed in both plasma and intracellular membranes of cells from almost all living organisms.