The first ligands to be discovered were synthetic and members of the halogenated aromatic hydrocarbons (polychlorinated dibenzodioxins, dibenzofurans and biphenyls) and polycyclic aromatic hydrocarbons (3-methylcholanthrene, benzo(a)pyrene, benzanthracenes and benzoflavones).
receptor | LDL receptor | Receptor (biochemistry) | Continuous erythropoietin receptor activator | GABA receptor | Epidermal growth factor receptor | NMDA receptor | hydrocarbon | Sensory receptor | receptor (biochemistry) | metabotropic glutamate receptor | Hydrocarbon | 5-HT2A receptor | VLDL receptor | TGF beta receptor 2 | receptor antagonist | epidermal growth factor receptor | aryl | 5-HT receptor | RAR-related orphan receptor alpha | Metabotropic glutamate receptor 5 | Metabotropic glutamate receptor 2 | G protein-coupled receptor | AMPA receptor | Adenosine A1 receptor | Toll-like receptor | TNF receptor associated periodic syndrome | taste receptor | Sigma-1 receptor | Receptor antagonist |
CLOCK (circadian locomotor output cycles kaput) was first cloned in mouse and BMAL1 (brain and muscle aryl hydrocarbon receptor nuclear translocator (ARNT)-like 1) is the primary homolog of Drosophila CYC.