Mas-related G protein-coupled receptors are sensory neuron-specific G protein-coupled receptors that are usually involved in the development and function of nociceptive neurons and may also regulate the sensation or modulation of pain. MRGD (MAS-related GPR, member D), also known as MRGPRD or TGR7, is a 321 amino acid multi-pass membrane protein that belongs to the G-protein coupled receptor 1 family and the Mas subfamily. MRGD is suggested to function specifically as a receptor for beta-alanine, a naturally occurring beta amino acid. Beta-alanine induces Ca2+ influx and decreases forskolin-stimulated cAMP production in cells expressing MRGD. Neurons of outer epidermis that express MRGD act as nociceptors in which they respond indirectly to external stimuli by detecting ATP release in the skin. MRGD is encoded by a gene located on human chromosome 11q13.2.