Pyroglutamylated RF-amide peptide receptor (QRFPR)

The **Pyroglutamylated RF-amide peptide receptor (QRFPR)**, also known as **GPR103**, is a class A G protein-coupled receptor (GPCR) with seven transmembrane domains that is activated by peptides containing a C-terminal RF-amide motif, notably QRFP and 26RFa[1][2][3]. This receptor mediates key neuroendocrine processes, including **regulation of energy homeostasis, appetite, and adrenal function**. QRFPR is predominantly expressed in the brain and acts primarily through coupling to Gq proteins to initiate intracellular signaling cascades[1][2]. Its endogenous ligands, including QRFP, P518, and 26RFa, induce receptor activation, leading to a cascade that influences metabolic and cardiovascular functions[1][2][3]. Structural studies have identified unique extracellular domain interactions that are crucial for ligand specificity and receptor activation[1][2]. Given its central role in metabolic regulation, **QRFPR is considered a promising therapeutic target** for obesity, diabetes, and eating disorders, although challenges remain regarding selectivity and potential systemic effects due to its broad physiological roles[1][2].

Other names

G-protein coupled receptor 103GPR103Orexigenic neuropeptide QRFP receptorPeptide P518 receptorAQ27SP9155

Agonists bind to QRFPR activating downstream G protein signaling that modulates appetite, energy homeostasis, and neuroendocrine outputs[1][2][3].