Stomatin.

Stomatin is a 31-kDa integral membrane protein, named after the rare human haemolytic anaemia hereditary stomatocytosis. In some cases of this anaemia, in which the red cells leak sodium and potassium ions, this protein is absent from the membrane, immediately suggesting that it has a role in the regulation of ion transport. The protein has a single hydrophobic domain, presumed to be membrane-associated, is phosphorylated, and is widely distributed in animal tissues. Mutations of a homologue in sensory nerve cells of the nematode Caenorhabditis elegans disrupt a neuronal transduction mechanism, in which mechanosensory information is relayed to an ion channel, whose opening initiates an action potential. It could be that this protein is a molecular link in a genetic stretch-sensitive system. Abnormalities of red cell ion transport are well known in human hypertension, but the molecular basis has never been elucidated: this protein and its functional associates, operating in a stretch- or pressure-sensitive complex, might be important.