An orphan receptor is an apparent receptor that has a similar structure to other identified receptors but whose endogenous ligand has not yet been identified. If a ligand for an orphan receptor is later discovered, the receptor is referred to as an "adopted orphan".
Famous quotes containing the words orphan and/or receptor:
“The obvious parallels between Star Wars and The Wizard of Oz have frequently been noted: in both there is the orphan hero who is raised on a farm by an aunt and uncle and yearns to escape to adventure. Obi-wan Kenobi resembles the Wizard; the loyal, plucky little robot R2D2 is Toto; C3PO is the Tin Man; and Chewbacca is the Cowardly Lion. Darth Vader replaces the Wicked Witch: this is a patriarchy rather than a matriarchy.”
—Andrew Gordon, U.S. educator, critic. “The Inescapable Family in American Science Fiction and Fantasy Films,” Journal of Popular Film and Television (Summer 1992)
“The disinterest [of my two great-aunts] in anything that had to do with high society was such that their sense of hearing ... put to rest its receptor organs and allowed them to suffer the true beginnings of atrophy.”
—Marcel Proust (1871–1922)