Discovery
Historically, receptors were discovered by using ligands to "fish" for their receptors. Hence by definition, these receptors were not orphans. However with modern molecular biology techniques such as screening of cDNA libraries, it becomes possible to identify related receptors based on sequence similarity to known receptors without knowing what their ligands are.
Read more about this topic: Orphan Receptor
Famous quotes containing the word discovery:
“I have known no experience more distressing than the discovery that Negroes didn’t love me. Unutterable loneliness claimed me. I felt without roots, like a man without a country ...”
—Sarah Patton Boyle, U.S. civil rights activist and author. The Desegregated Heart, part 1, ch. 10 (1962)
“The gain is not the having of children; it is the discovery of love and how to be loving.”
—Polly Berrien Berends (20th century)
“However backwards the world has been in former ages in the discovery of such points as GOD never meant us to know,—we have been more successful in our own days:Mthousands can trace out now the impressions of this divine intercourse in themselves, from the first moment they received it, and with such distinct intelligence of its progress and workings, as to require no evidence of its truth.”
—Laurence Sterne (1713–1768)