Progesterone inhibition of uterine nuclear estrogen receptor: dependence on RNA and protein synthesis.

AUTOR(ES)

Evans, R W

RESUMO

Progesterone treatment was found previously to reduce nuclear estrogen receptor (Re) rapidly (2-4 hr) in the hamster uterus in vivo. The present study was done to determine whether this inhibitory effect of progesterone on uterine nuclear Re could be demonstrated in vitro ad whether progesterone action was dependent on RNA and protein synthesis. A uterine strip system was used in which estradiol pretretment caused cytosol Re translocation to the nucleus and increased synthesis of cytosol progesterone receptor (Rp) during a 16-hr incubation. When progesterone was added to the medium 4 hr before the end of the incubation, cytosol Rp was depleted and nuclear Re was greatly reduced. Further experiments done with actinomycin D, puromycin, and cycloheximide indicated that the progesterone-induced loss of uterine nuclear Re was dependent on RNA and protein synthesis. These results suggest that progesterone reduced nuclear Re through a mechanism involving Rp translocation and the induction of RNA and protein synthesis, a product of which is active in degrading or otherwise inactivating nuclear Re.

Documentos Relacionados

• Dependence of "early" lambda bacteriophage RNA synthesis on bacteriophage-directed protein synthesis.
• Role of RNA Synthesis in the Estrogen Induction of a Specific Uterine Protein*
• Estrogen-induced synthesis of a specific uterine protein.
• Evidence for depression of nuclear protein synthesis and concomitant stimulation of nuclear RNA synthesis during early estrogen action.
• Purification of a soluble template-dependent rhinovirus RNA polymerase and its dependence on a host cell protein for viral RNA synthesis.