Chloride channels
chloride channels
Chloride channels are a superfamily of poorly understood ion channels consisting of approximately 13 members.  Chloride channels display a variety of important physiological and cellular roles that include regulation of pH, volume homeostasis, organic solute transport, cell migration, cell proliferation and differentiation. Based on sequence homology the chloride channels can be subdivided into a number of groups. The importance of one such group, the CLC family of chloride channels, can be seen from the diseases that develop when the channel does not function normally.  This family of ion channels contains 10 or 12 transmembrane helices. Each protein forms a single pore. It has been shown that some members of this family form homodimers. In terms of primary structure, they are unrelated to known cation channels or other types of anion channels. Three CLC subfamilies are found in animals. CLC-1 ( P35523 ) is involved in setting and restoring the resting membrane potential of skeletal muscle, while other channels play important parts in solute concentration mechanisms in the kidney. These proteins contain two CBS domains. Chloride channels are also important for maintaining safe ion concentrations within plant cells.