| Type: | Domain | Name: | Bicarbonate transporter, C-terminal |
| Description: | Bicarbonate (HCO3-) transport mechanisms are the principal regulators of pH in animal cells. Such transport also plays a vital role in acid-base movements in the stomach, pancreas, intestine, kidney, reproductive organs and the central nervous system. Functional studies have suggested four different HCO3-transport modes. Anion exchanger proteins exchange HCO3-for Cl-in a reversible, electroneutral manner []. Na+/HCO3-co-transport proteins mediate the coupled movement of Na+and HCO3-across plasma membranes, often in an electrogenic manner []. Na-driven Cl-/HCO3-exchange and K+/HCO3-exchange activities have also been detected in certain cell types, although the molecular identities of the proteins responsible remain to be determined.Sequence analysis of the two families of HCO3-transporters that have been cloned to date (the anion exchangers and Na+/HCO3-co-transporters) reveals that they are homologous. This is not entirely unexpected, given that they both transport HCO3-and are inhibited by a class of pharmacological agents called disulphonic stilbenes []. They share around ~25-30% sequence identity, which is distributed along their entire sequence length, and have similar predicted membrane topologies, suggesting they have ~10 transmembrane (TM) domains.This domain is found at the C terminus of many bicarbonate transport proteins. It is also found in some plant proteins responsible for boron transport []. In these proteins it covers almost the entire length of the sequence. | Short Name: | HCO3_transpt_C |
