Selectivity · by receptor
MC1R: ligand selectivity
Melanocortin 1 receptor · skin · pigment
7 catalogued melanocortin ligands bind MC1R with a curated affinity. The tightest is Afamelanotide (≈0.10 nM). The most MC1R-selective is Agouti (ASIP), which prefers MC1R by 20× — because the five receptors share one binding core, a ligand that truly prefers MC1R is the exception, not the rule.
Most MC1R-selective
Ligands whose tightest target of the five receptors is MC1R — ranked by selectivity window (how cleanly they prefer it).
- Agouti (ASIP)20×Selective · blocker
- Afamelanotide10×Selective
- Melanotan II2.5×Broadly non-selective
- α-MSH1.6×Broadly non-selective
Everything that binds MC1R
Ranked by binding strength. Filled bars are agonists; blue bars are blockers. Select a ligand for its full fingerprint across all five receptors.
Binding is not the whole story: these bars show how tightly each ligand holds MC1R, not what the receptor then does once bound. For the receptor's own biology — where it sits, what it controls, and what breaks when it fails — see the MC1R page. To put any one ligand next to the others, use the selectivity visualizer; for every value with its citation, the binding matrix.
Affinity values from the IUPHAR/BPS Guide to PHARMACOLOGY; selectivity is derived from them. Educational resource, not medical advice — see the editorial standards.