Effects of palmitoylation on the diffusional movement of BKCa channels in live cells

BKCa channels are palmitoylated at a cluster of cysteine residues within the cytosolic linker connecting the 1st and 2nd transmembrane domains, and this lipid modification affects their surface expression. To verify the effects of palmitoylation on the diffusional dynamics of BKCa channels, we investigated their lateral movement. Compared to wild-type channels, the movement of mutant palmitoylation-deficient channels was much less confined and close to random. The diffusion of the mutant channel was also much faster than that of the wild type. Thus, the lateral movement of BKCa channels is greatly influenced by palmitoylation.