Rapid homologous up-regulation of binding capacity of androgen receptors in intact cells.
Incubation of MCF 7 cells with 5 alpha-dihydrotestosterone (DHT) at 37 degrees C led to a 70% increase in the Bmax of androgen receptor, as compared to the values measured at 2 degrees C, without detectable changes in equilibrium dissociation constants. When MCF 7 cells were incubated with hormone at 2 degrees C, to reach steady-state levels of androgen-receptor complex, a subsequent temperature shift to 37 degrees C induced a rapid (t 1/2 = 3 min) cycloheximide-insensitive increase in DHT binding to androgen receptor. MCF 7 cell treatments at 37 degrees C either before or after incubation with DHT at 2 degrees C showed that up-regulation of binding capacity of androgen receptor could be observed only if hormone is present during incubation at physiological temperature.
Rossini
G P
GP
Istituto di Chimica Biologica, Università di Modena, Italy.
D001943:Breast Neoplasms; D002460:Cell Line; D013196:Dihydrotestosterone / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007700:Kinetics; D011944:Receptors, Androgen / Q000187:drug effects / Q000378:metabolism*; D013696:Temperature; D015854:Up-Regulation
D011944:Receptors, Androgen; D013196:Dihydrotestosterone