Recombinant Human OPRD1 protein

The delta-opioid receptor (δ-OR, encoded by the *OPRD1* gene) is a G protein-coupled receptor (GPCR) predominantly expressed in the central and peripheral nervous systems. It plays a critical role in modulating pain perception, emotional responses, and neuropsychiatric functions by binding endogenous opioid peptides (e.g., enkephalins) and synthetic ligands. Unlike mu-opioid receptors (associated with analgesia and addiction), δ-OR activation is linked to anxiolytic, antidepressant, and less addictive properties, making it a promising therapeutic target for chronic pain, mood disorders, and addiction.

Recombinant OPRD1 proteins are engineered in vitro using heterologous expression systems (e.g., mammalian cells, *E. coli*, or yeast) to study receptor structure, signaling, and ligand interactions. These proteins often include tags (e.g., His-tag, FLAG) for purification and detection. Researchers utilize OPRD1 recombinant proteins to elucidate ligand-binding mechanisms, receptor dimerization, and downstream signaling pathways (e.g., Gi/o protein coupling, MAPK/ERK activation). Structural studies (X-ray crystallography, cryo-EM) of recombinant δ-OR have revealed key conformational changes during activation, aiding rational drug design.

Despite challenges like low native expression and instability, recombinant OPRD1 enables high-throughput screening of selective agonists/antagonists and probes receptor dysfunction in neurological diseases. Its study bridges gaps in opioid receptor pharmacology, offering insights into safer analgesics and neuropsychiatric therapies.