The EBP gene (EBP stands for emopamil-binding protein) is a protein-coding gene located on chromosome Xp11.23. The protein encoded by this gene, an isomerase, is an integral membrane protein of the endoplasmic reticulum. It is a binding protein with high affinity for the antiischemic phenylalkylamine Ca2+ antagonist [3H]emopamil and the photoaffinity marker [3H]azidopamil. It resembles sigma receptors and may belong to a superfamily of high-affinity drug-binding proteins in the endoplasmic reticulum of various tissues.
This protein shares structural features with bacterial and eukaryotic drug transport proteins. It has four putative transmembrane segments and contains two conserved glutamate residues that may be involved in the transport of cationic amphiphiles.