Phenylalkylamine Ca2+Antagonist Binding Protein

摘要: We recently characterized (Moebius, F. F., Burrows, G. G., Striessnig, J., and Glossmann H.(1993) Mol. Pharmacol. 43, 139-144) purified Hanner, M., Knaus, H. Weber, Glossmann, H.(1994) J. Biol. Chem. 269, 29314-29320) a binding protein for the phenylalkylamine Ca2+ antagonist emopamil. The emopamil-binding (EBP) acts as high affinity acceptor several antiischemic drugs thus represents potential common molecular target drug action. Degenerate oligonucleotides were synthesized according to N-terminal amino acid sequence of EBP used amplify guinea pig cDNA with reverse transcriptase-polymerase chain reaction clone full-length cDNAs from human liver libraries. coded 229 (guinea pig) 230 (human) 27-kDa polypeptides without significant homology any known protein. However, shared structural features pro- eukaryotic transport proteins. identity between was 73%. Hydrophobicity plots predicted four transmembrane segments. C terminus contained lysine-rich consensus retrieval type I integral membrane proteins endoplasmic reticulum. heterologous expression in Saccharomyces cerevisiae demonstrated that alone is sufficient form drug- cation-binding domains identical [3H]-emopamil-binding site liver. Northern Western blot analysis revealed abundance epithelial tissues liver, bowel, adrenal gland, testis, ovary, uterus low densities brain, cerebellum, skeletal muscle, heart. suggested be first structurally member family microsomal carrying so called ς-binding sites.