Proteolytic activity of the purified hormone-binding subunit in the estrogen receptor.

AUTOR(ES)

Molinari, A M

RESUMO

The hormone-binding subunit of the calf uterus estradiol receptor was purified as a hormone-free molecule. Immunoaffinity chromatography with a specific monoclonal antibody was used as the final step. The purified subunit was specifically labeled by radioactive diisopropyl fluorophosphate. The diisopropyl fluorophosphate-labeled amino acid was serine. The purified receptor was able to release the fluorogenic or chromogenic group from synthetic peptides containing phenylalanine at the carboxyl terminus. This occurred only in the presence of estradiol and was hampered by aprotinin and diisopropyl fluorophosphate. Estradiol-dependent hydrolytic activity was also found in the eluate from gel slices after SDS/PAGE of purified receptor. This activity comigrated with the renaturable estradiol-binding activity. The estradiol antagonists 4-hydroxytamoxifen and ICI 164,384 as well as other steroid hormones were unable to activate this hydrolytic activity.

Documentos Relacionados

• A systematic mutational analysis of hormone-binding determinants in the human growth hormone receptor.
• Localization and synthesis of the hormone-binding regions of the human thyrotropin receptor.
• Rsk2 allosterically activates estrogen receptor α by docking to the hormone-binding domain
• Evidence for monomeric and oligomeric hormone-binding domains in affinity-purified gonadotropin receptor from rat ovary.
• Long-term effects of estrogen on avian liver: estrogen-inducible switch in expression of nuclear, hormone-binding proteins.