Erythrocyte band 7 integral membrane protein isoform a, also known as STOM, is a member of a highly conserved family of integral membrane proteins. STOM may regulate ACCN1 and ACCN3 gating. It is a membrane protein involved in regulation of monovalent cation transport through lipid membranes. A second function of STOM may be to act as a cytoskeletal anchor. It is a major lipid-raft component of erythrocytes and epithelial cells, and is also an abundant platelet protein. Recombinant human STOM protein, fused to His-tag at N-terminus, was expressed in E.coli.