Melanocortin receptor 4
Also known as: MC4R
Function
G protein-coupled receptor that binds melanocyte-stimulating hormones (alpha- and beta-MSH) and corticotropin/ACTH, which are peptide products of the POMC precursor. Functions as a central component of the leptin-melanocortin pathway, which is essential for maintaining energy homeostasis. Upon activation, couples to G(s) protein, stimulating adenylate cyclase and the cAMP-dependent signaling pathway, which promotes anorexogenic signaling in the hypothalamus and contributes to a negative energy balance. Regulates food intake: activation by agonists suppresses appetite, whereas the antagonist Agouti-related protein/AGRP precludes agonist-induced signaling, thereby stimulating appetite. Modulates the firing activity of neurons in paraventricular nucleus (PVN) of the hypothalamus via alpha-MSH and AGRP regulation of inwardly rectifying potassium channel KCNJ13 closure, independently of G(s) signaling. In the PVN, also interacts with opsin 3/OPN3, which couples to G(i/o) proteins to inhibit MC4R-mediated cAMP signaling, thereby promoting food intake. In intestinal epithelial cells, contributes to inhibition of hepatic glucose production via nesfatin-1/NUCB2, leading to increased cAMP levels and glucagon-like peptide 1 (GLP-1) secretion. Interaction with MGRN1 displaces the G(s) protein, further decreasing MC4R signaling activity. Also activated by gamma-MSH, though with low potency.
Classification
- Family (Pfam)
- PF00001 7tm_1
- InterPro
- GPCR_Rhodpsn, GPCR_Rhodpsn_7TM, MC3-5R, Mcort_rcpt_4, Melcrt_ACTH_rcpt
- Functional cluster
- G Protein-Coupled Receptors
Experimental structures · PDB · 12
- 6W25 X-ray 2.75A
- 7AUE EM 2.97A
- 7F53 EM 3.00A
- 7F54 EM 3.00A
- 7F55 EM 3.10A
- 7F58 EM 3.10A
- 7PIU EM 2.58A
- 7PIV EM 2.86A
- 8QJ2 EM 3.40A
- 8WKY X-ray 2.90A
- 8WKZ X-ray 3.30A
- 9K3K EM 3.12A
A predicted model is available from AlphaFold.
Gene Ontology · 18
- GO:0005737 cytoplasm
- GO:0016020 membrane
- GO:0098804 non-motile cilium membrane
- GO:0005886 plasma membrane
- GO:0004978 corticotropin receptor activity
- GO:0004977 melanocortin receptor activity
- GO:0004980 melanocyte-stimulating hormone receptor activity
- GO:0042923 neuropeptide binding
- GO:0031625 ubiquitin protein ligase binding
- GO:0007189 adenylate cyclase-activating G protein-coupled receptor signaling pathway
- GO:0007188 adenylate cyclase-modulating G protein-coupled receptor signaling pathway
- GO:0007631 feeding behavior
- GO:0032099 negative regulation of appetite
- GO:2000252 negative regulation of feeding behavior
- GO:0045780 positive regulation of bone resorption
- GO:1903998 regulation of eating behavior
- GO:0060259 regulation of feeding behavior
- GO:1990680 response to melanocyte-stimulating hormone
Disease associations
- inherited obesity MONDO:0019182
Drugs targeting this protein · 5
- PF-00446687 agonist
- BREMELANOTIDE agonist
- SETMELANOTIDE agonist
- BREMELANOTIDE ACETATE agonist
- SETMELANOTIDE ACETATE agonist
Neighborhood · nearest proteins
Related proteins · sequence + function similarity
- Melanocortin receptor 4 1.00
- Melanocortin receptor 4 1.00
- Melanocortin receptor 4 1.00
- Melanocortin receptor 4 1.00
- Melanocortin receptor 4 1.00
- Melanocortin receptor 4 1.00
- Melanocortin receptor 5 0.98
- Melanocortin receptor 5 0.98
- Melanocortin receptor 4 0.98
- Melanocortin receptor 3 0.98
- Melanocortin receptor 5 0.98
- Melanocortin receptor 3 0.98
Co-cited proteins · studied together in the literature
- Nucleobindin-2 1 shared papers
- Adenylate cyclase type 3 1 shared papers
- Pro-opiomelanocortin 1 shared papers
- E3 ubiquitin-protein ligase MGRN1 1 shared papers
- Inward rectifier potassium channel 13 1 shared papers
- Melanocortin-2 receptor accessory protein 2 1 shared papers
- Agouti-related protein 1 shared papers
- Melanocortin receptor 3 1 shared papers
- Melanocyte-stimulating hormone receptor 1 shared papers
- Agouti-related protein 1 shared papers
- Melanocortin-2 receptor accessory protein 1 shared papers
- Inward rectifier potassium channel 13 1 shared papers
Literature · 25 cited papers
- Obesity due to MC4R deficiency is associated with reduced cholesterol, triglycerides and cardiovascular disease risk. Nat. Med. · 2025
- Hypothalamic opsin 3 suppresses MC4R signaling and potentiates Kir7.1 to promote food consumption. Proc. Natl. Acad. Sci. U.S.A. · 2025
- Intestinal NUCB2/nesfatin-1 regulates hepatic glucose production via the MC4R-cAMP-GLP-1 pathway. EMBO J. · 2024
- Structure reveals the activation mechanism of the MC4 receptor to initiate satiation signaling. Science · 2021
- Determination of the melanocortin-4 receptor structure identifies Ca2+ as a cofactor for ligand binding. Science · 2020
- Human gain-of-function MC4R variants show signaling bias and protect against obesity. Cell · 2019
- Subcellular localization of MC4R with ADCY3 at neuronal primary cilia underlies a common pathway for genetic predisposition to obesity. Nat. Genet. · 2018
- Functional characterization of a new human melanocortin-4 receptor homozygous mutation (N72K) that is associated with early-onset obesity. Mol. Biol. Rep. · 2014
- The melanocortin 4 receptor: oligomer formation, interaction sites and functional significance. Biochim. Biophys. Acta · 2013
- Mahogunin ring finger-1 (MGRN1) E3 ubiquitin ligase inhibits signaling from melanocortin receptor by competition with Galphas. J. Biol. Chem. · 2009
- MRAP and MRAP2 are bidirectional regulators of the melanocortin receptor family. Proc. Natl. Acad. Sci. U.S.A. · 2009
- The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). Genome Res. · 2004
- … and 13 more in the literature graph