Insights on glucocorticoid receptor activity modulation through the binding of rigid steroids

Autor: Presman, D.M., Alvarez, L.D., Levi, V., Eduardo, S., Digman, M.A., Martí, M.A., Veleiro, A.S., Burton, G., Pecci, A.
Jazyk: angličtina
Rok vydání: 2010
Předmět:
Models
Molecular
DNA drug complex
mifepristone
Electrophoretic Mobility Shift Assay
protein binding
immunoprecipitation
incubation time
binding affinity
glucocorticoid receptor
animal
conformational transition
dimerization
drug receptor binding
steroid
article
cell line
protein function
cell assay
unclassified drug
modulation
cell strain COS1
cell strain L 929
COS Cells
cell strain COS7
protein DNA interaction
Steroids
nuclear receptor coactivator 2
in vitro study
ligand binding
dexamethasone
cell strain BHK
dissociation
protein DNA binding
Cercopithecus
Molecular Dynamics Simulation
gel mobility shift assay
oligomerization
Cercopithecus aethiops
in vivo study
Receptors
Glucocorticoid
drug mechanism
Animals
controlled study
structure activity relation
cell culture
cell type
DNA
molecular dynamics
chemical structure
glucocorticoid receptor antagonist
computer model
genetic transfection
steroid binding
21 hemisuccinate 6
19 epoxyprogesterone
metabolism
21 hydroxy 6
19 epoxyprogesterone
Zdroj: PLoS ONE 2010;5(10)
Biblioteca Digital (UBA-FCEN)
Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
instacron:UBA-FCEN
Popis: Background: The glucocorticoid receptor (GR) is a transcription factor that regulates gene expression in a ligand-dependent fashion. This modular protein is one of the major pharmacological targets due to its involvement in both cause and treatment of many human diseases. Intense efforts have been made to get information about the molecular basis of GR activity. Methodology/Principal Findings: Here, the behavior of four GR-ligand complexes with different glucocorticoid and antiglucocorticoid properties were evaluated. The ability of GR-ligand complexes to oligomerize in vivo was analyzed by performing the novel Number and Brightness assay. Results showed that most of GR molecules form homodimers inside the nucleus upon ligand binding. Additionally, in vitro GR-DNA binding analyses suggest that ligand structure modulates GRDNA interaction dynamics rather than the receptor's ability to bind DNA. On the other hand, by coimmunoprecipitation studies we evaluated the in vivo interaction between the transcriptional intermediary factor 2 (TIF2) coactivator and different GR-ligand complexes. No correlation was found between GR intranuclear distribution, cofactor recruitment and the homodimerization process. Finally, Molecular determinants that support the observed experimental GR LBD-ligand/TIF2 interaction were found by Molecular Dynamics simulation. Conclusions/Significance: The data presented here sustain the idea that in vivo GR homodimerization inside the nucleus can be achieved in a DNA-independent fashion, without ruling out a dependent pathway as well. Moreover, since at least one GR-ligand complex is able to induce homodimer formation while preventing TIF2 coactivator interaction, results suggest that these two events might be independent from each other. Finally, 21-hydroxy-6,19-epoxyprogesterone arises as a selective glucocorticoid with potential pharmacological interest. Taking into account that GR homodimerization and cofactor recruitment are considered essential steps in the receptor activation pathway, results presented here contribute to understand how specific ligands influence GR behavior. © 2010 Presman et al. Fil:Presman, D.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Alvarez, L.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Levi, V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Martí, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Veleiro, A.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Burton, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Pecci, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Databáze: OpenAIRE
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