This antibody is specific for the sigma-1 receptor (sigma-1R, Oprs1 protein, opioid receptor sigma 1) protein. On western blots, it identifies the target band at ~25 kDa. Reactivity has been confirmed with rat brain, rat liver, and mouse brain homogenates. Based on amino acid sequence identity, reactivity with human, bovine, dog, and ermine is expected.
The sigma receptor (sigma-1R, Oprs1 protein, opioid receptor sigma 1) and its agonists are implicated in a variety of cellular functions, biological processes and diseases, including cancer biology, psychosis, regulation of neurotransmitter function, motor, endocrine and immune systems. Two sigma receptors, -1 and -2 are presently known and classified based on their ability to bind a variety of ligands. The sigma-1 receptor interacts with a variety of psychotomimetic drugs, including cocaine and amphetamines. As indicated by its previous name, opioid receptor sigma 1 (OPRS1), was erroneously thought to function as an opioid receptor; it is now thought to be a non-opioid receptor. Alternative splicing of its gene results in transcript variants encoding distinct isoforms. It is distinct from any known receptor class and lacks significant homology to known mammalian proteins but possesses some homology with fungal sterol isomerases. The predicted structure of this 25 kDa protein depicts two transmembrane domains with both N- and C-terminal tails residing in the cytoplasm. The sigma-1 receptor is highly expressed in the central nervous system, heart, ovary, kidney, testes, liver, placenta, and embryonic stem cells. Both sigma receptors are also highly expressed in tumor cell lines from various tissues, including small- and non-small-cell lung carcinoma, large-cell carcinoma, renal carcinoma, colon carcinoma, sarcoma, brain tumors, breast cancer, emlanoma, glioblastoma, neuroblastoma, and prostate cancer. The exact mechanism how sigma-1R affects cancer biology is not known. Some hypotheses include modulation of ion channel activity, cytoskeletal proteins such as ankyrin, intracellular calcium levels, or sphingolipid levels. Recent evidence also suggests that sigma-1R is important in the compartmentalization/transport of ER-synthesized lipids. Two polymorphisms of the sigma-1R gene, which decrease expression of the gene, are associated with occurrence of Alzheimer's disease.
For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.
Protein Aliases: aging-associated gene 8 protein; ALS16; hSigmaR1; opioid receptor, sigma 1; OPRS1; SIG-1R; sigma 1 receptor variant SR-1D; sigma 1-type opioid receptor; sigma non-opioid intracellular receptor 1; sigma1-receptor; sigma1R; SR-BP; SR-BP1; SR31747 binding protein 1; SRBP
Gene Aliases: Oprs1; sigma1R