title: Conformational effects of Lys191 in the human GnRH receptor: mutagenesis and molecular dynamics simulations studies.
abstract: In the present study, we analyzed the role of Lys191 on function, structure, and dynamic behavior of the human GnRH receptor (hGnRHR) and the formation of the Cys14-Cys200 bridge, which is essential for receptor trafficking to the plasma membrane. Several mutants were studied; mutants lacked either the Cys14-Cys200 bridge, Lys191 or both. The markedly reduced expression and function of a Cys14Ser mutant lacking the 14-200 bridge, was nearly restored to wild-type/DeltaLys191 levels upon deletion of Lys191. Lys191 removal resulted in changes in the dynamic behavior of the mutants as disclosed by molecular dynamics simulations: the distance between the sulfur- (or oxygen-) sulfur groups of Cys (or Ser)14 and Cys200 was shorter and more constant, and the conformation of the NH(2)-terminus and the exoloop 2 exhibited fewer fluctuations than when Lys191 was present. These data provide novel information on the role of Lys191 in defining an optimal configuration for the hGnRHR intracellular trafficking and function.
authors.affiliation: Research Unit in Reproductive Medicine, Hospital de Ginecobstetricia Luis Castelazo Ayala, Instituto Mexicano del Seguro Social, Apartado Postal 99-065, Unidad Independencia, Mexico D.F. CP 10101, Mexico.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Jardón-Valadez
authors.forename: Arturo
authors.initials: A
authors.lastname: Aguilar-Rojas
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Maya-Núñez
authors.forename: Alfredo
authors.initials: A
authors.lastname: Leaños-Miranda
authors.forename: Angel
authors.initials: A
authors.lastname: Piñeiro
authors.forename: P Michael
authors.initials: PM
authors.lastname: Conn
authors.forename: Alfredo
authors.initials: A
authors.lastname: Ulloa-Aguirre
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002064:Buserelin / Q000493:pharmacokinetics; D019556:COS Cells; D002522:Chlorocebus aethiops; D003198:Computer Simulation; D006801:Humans; D006860:Hydrogen Bonding; D008239:Lysine / Q000235:genetics / Q000502:physiology*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D050505:Mutant Proteins / Q000737:chemistry; D011487:Protein Conformation; D021381:Protein Transport / Q000235:genetics; D011966:Receptors, LHRH / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000502:physiology
chemical_list: D050505:Mutant Proteins; D011966:Receptors, LHRH; D008239:Lysine; D002064:Buserelin