title: Goat endometrial heat shock protein-90 (Hsp-90): development of an expedient method for its purification and observations on its intracellular movement.
abstract: An expedient method has been developed by which goat uterine Hsp-90 could be isolated and purified to homogeneity in less than 1day. The yield is roughly 1mg from 60g tissue. This method takes into advantage three of our earlier observation that (a) Hsp-90 gets linked to the non-activated estrogen receptor (naER) in the presence of 10mM sodium molybdate; (b) naER, but not Hsp-90 binds to phosphocellulose and (c) exposure to estradiol facilitates dissociation of Hsp-90 from naER through estradiol binding to naER and the possible change in naER conformation. Intracellular movement of Hsp-90 and naER was monitored in goat endometrial cells in culture following exposure of the cells to estradiol. Confocal microscopic analysis revealed a clear presence of both proteins within the nucleus within 3h after exposure to estradiol. Whether Hsp-90 has its own nuclear-transport machinery is debatable. Being an actin-binding protein, there is a distinct possibility that the nuclear entry of Hsp-90 is actin dependent. The functional significance of the nuclear entry of Hsp-90, along with naER, remains to be determined; it may, however, be speculated that the Hsp-90 might be directly involved in the naER to nER II transformation by functioning as a molecular chaperone and helping the protein in re-orienting its structural organization.
authors.affiliation: MIMS Research Foundation, Valayanad Temple Road Junction, Mankav Bye Pass, Mankav, Calicut 673016, Kerala, India.
authors.forename: Parvathi
authors.initials: P
authors.lastname: Anilkumar
authors.forename: Vidya S
authors.initials: VS
authors.lastname: Krishnan
authors.forename: Raghava Varman
authors.initials: RV
authors.lastname: Thampan
mesh_terms: D000818:Animals; D001671:Biochemistry / Q000379:methods*; D002478:Cells, Cultured; D004717:Endometrium / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006041:Goats / Q000378:metabolism*; D018841:HSP90 Heat-Shock Proteins / Q000302:isolation & purification* / Q000378:metabolism*; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism*; D018613:Microscopy, Confocal; D021381:Protein Transport / Q000187:drug effects; D011960:Receptors, Estrogen / Q000378:metabolism
chemical_list: D018841:HSP90 Heat-Shock Proteins; D011960:Receptors, Estrogen; D004958:Estradiol