Mas-related G protein-coupled receptor D (MrgD)

Mas-related G protein-coupled receptor D (MrgD or MRGPRD) is a member of the Mas-related GPCR family expressed primarily in small-diameter sensory neurons, especially dorsal root ganglion (DRG) neurons, and found in other tissues such as retina and heart. MrgD is activated by endogenous ligands including β-alanine and alamandine, triggering Gi protein-coupled signaling that regulates nociception (pain and itch), vascular tone, and responses to tissue injury. Recent structural studies have elucidated its unique activation mechanism, which may be both ligand-dependent (e.g., β-alanine binding) and constitutive. MrgD and its ligands are implicated in the modulation and potential treatment of neuropathic pain, cardiovascular remodeling, and retinal neurovascular dysfunction, making it a promising, albeit still experimental, therapeutic target.

Other names

MrgDMRGPRDMas-related GPRDMas-related G protein–coupled receptor d

Agonists (e.g., β-alanine, alamandine): activate MrgD, leading to Gi protein signaling and downstream effects such as modulation of neuronal excitability or attenuation of proinflammatory pathways. Antagonism or genetic deletion: may reduce pain signaling or prevent maladaptive cardiac or retinal remodeling