A locus of the gonadotropin-releasing hormone receptor that differentiates agonist and antagonist binding sites. - Zhou,W.; Rodic,V.; Kitanovic,S.; Flanagan,C.A.; Chi,L.; Weinstein,H.; Maayani,S.; Millar,R.P.; Sealfon,S.C. (J Biol Chem, 1995)