Juxtaposition of the Steroid Binding Domain-like I and II Regions Constitutes a Ligand Binding Site in the σ-1 Receptor

σ-1 receptors represent unique binding sites that are capable of interacting with a wide range of compounds to mediate different cellular events. The composition of the ligand binding site of this receptor is unclear, since no NMR or crystal structures are available. Recent studies in our laboratory using radiolabeled photoreactive ligands suggested that the steroid binding domain-like I (SBDLI) (amino acids 91-109) and the steroid binding domain-like II (SBDLII) (amino acids 176-194) regions are involved in forming the ligand binding site(s) (Chen, Y., Hajipour, A. R., Sievert, and A. Hajipour, A. R., and A. this this our Hajipour, A. R., Y., and A. to the in the of the σ-1 receptor and in the of a σ-1 receptor in a or and the to the in the receptor the to the in the receptor a in the and regions are to in a ligand binding site of the σ-1 σ-1 receptors represent unique binding sites that are capable of interacting with a wide range of compounds to mediate different cellular events. The composition of the ligand binding site of this receptor is unclear, since no NMR or crystal structures are available. Recent studies in our laboratory using radiolabeled photoreactive ligands suggested that the steroid binding domain-like I (SBDLI) (amino acids 91-109) and the steroid binding domain-like II (SBDLII) (amino acids 176-194) regions are involved in forming the ligand binding site(s) (Chen, Y., Hajipour, A. R., Sievert, and A. Hajipour, A. R., and A. this this our Hajipour, A. R., Y., and A. to the in the of the σ-1 receptor and in the of a σ-1 receptor in a or and the to the in the receptor the to the in the receptor a in the and regions are to in a ligand binding site of the σ-1 The receptors represent unique and binding sites that are or receptors the receptors receptors the of or receptors the receptors to to a receptor of the receptor the σ-1 receptor and the are ligand binding and A. A. are in different and studies that the σ-1 receptor is to a wide range of A. 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