Orphan 7-TM Receptors
Orphan 7-TM receptors (orphan GPCRs) are receptors for which there are no defined ligands. Traditionally, receptors are characterized by specific ligands and stimuli; the search for ligands of orphan receptors is therefore akin to reverse-engineering this process.
Orphan 7-TM Receptor Agonists |
|
|---|---|
| Cat. No. | Product Name / Activity |
| 6544 | CID 1375606 |
| GPR27 agonist | |
| 0504 | Diphenyleneiodonium chloride |
| GPR3 agonist; also inhibits NOS and NADPH oxidases | |
| 6784 | FTBMT |
| Potent and selective GPR52 agonist; orally bioavailable and BBB permeable | |
| 5666 | JNJ 63533054 |
| Potent and selective GPR139 agonist | |
| 5151 | Prosaptide TX14(A) |
| Potent GPR37 and GPR37L1 agonist | |
| 5355 | TC-G 1008 |
| Potent and selective GPR39 agonist | |
Orphan 7-TM Receptor Inverse Agonists |
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| Cat. No. | Product Name / Activity |
| 6931 | AF 64394 |
| Potent and selective GPR3 inverse agonist | |
Orphan 7-TM Receptor Antagonists |
|
| Cat. No. | Product Name / Activity |
| 7445 | GPR52 Comp-43 |
| GPR52 receptor antagonist | |
| 5203 | NIBR 189 |
| Potent and selective EBI2 (GPR183) receptor antagonist | |
Orphan 7-TM Receptor Modulators |
|
| Cat. No. | Product Name / Activity |
| 5722 | Ogerin |
| Selective positive allosteric modulator at GPR68 | |
Orphan 7-TM receptors (orphan GPCRs) are receptors for which there are no defined ligands. Traditionally, receptors are characterized by specific ligands and stimuli; the search for ligands of orphan receptors is akin to reverse-engineering this process, since the receptors have been identified but they are responding to as-yet unidentified endogenous ligands. There are approximately 150 orphan 7-TM receptors, subdivided into three classes: Class A, Class B and Class C. Orphan G-protein coupled receptors are usually identified by number (e.g. GPR35, GPR139) and as they are 'de-orphanized' (by discovery of ligand), they sometimes maintain this prefix (e.g. GPR55). Recently 'de-orphanized' GPCRs include the neuropeptide receptor GPR171.
Screening of putative ligands, reverse pharmacology and the prediction of candidate ligands using structural similarities are three of the methods currently used to isolate ligands for these orphan receptors. Putative ligands for some of the orphan receptors include kynurenic acid (GPR35) and motilin (GPR38). Generation of synthetic ligands for orphan receptors also holds great therapeutic potential: the melanin-concentrating hormone receptor is one such example of a de-orphanized receptor that has developed into a target for obesity, anxiety and depression.There has been great interest in the function of orphan receptors; elucidating the cellular interactions involving them may lead to a greater understanding of existing processes.