The most obvious difference between the cytoplasmic and nuclear-bound estrogen receptor forms (CER and NER respectively) is their molecular size/conformation. This study examined whether any differences in their estradiol and DNA-binding, under non-activation (2h, 4°C) and activation (2h, 4°C + 30 min. 25°C) conditions could be attributed to their molecular characteristics. Baboon endometrial CER and 400 mM KCl-extracted NER were desalted on Sephadex G-25 mini-columns and evaluated for estradiol uptake and DNA binding abilities. The major observation was that Sephadex G-25 (exclusion limit 5kDa) not only removed the salt but also trapped some low molecular weight moieties (LMWM), possibly released by salt-induced dissociation from the NER-complexes. Consequently, there was a decrease in the concentration of NER but not CER, and its DNA-binding ability. It may be concluded that a) LMWM participates in receptor conformation, enhancing estradiol binding and subsequent activation/transformation and b) this phenomenon may be nuclear in situ.
|Original language||English (US)|
|Number of pages||2|
|Journal||Medical Science Research|
|State||Published - Jan 1 1987|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)