title: Quercetin suppresses heat shock-induced nuclear translocation of Hsp72.
abstract: The effect of quercetin and heat shock on the Hsp72 level and distribution in HeLa cells was studied by Western blotting, indirect immunofluorescence and immunogold electron microscopy. In control cells and after quercetin treatment, Hsp72 was located both in the cytoplasm and in the nucleus in comparable amounts. After hyperthermia, the level of nuclear Hsp72 raised dramatically. Expression of Hsp72 in cytoplasm was also higher but not to such extent as that observed in the nucleus. Preincubation of heated cells with quercetin inhibited strong Hsp72 expression observed after hyperthermia and changed the intracellular Hsp72 distribution. The cytoplasmic level of protein exceeded the nuclear one, especially around the nucleus, where the coat of Hsp72 was noticed. Observations indicating that quercetin was present around and in the nuclear envelope suggested an involvement of this drug in the inhibition of nuclear translocation. Our results indicate that pro-apoptotic activity of quercetin may be correlated not only with the inhibition of Hsp72 expression but also with suppression of its migration to the nucleus.
authors.affiliation: Department of Comparative Anatomy and Anthropology, Maria Curie-Sklodowska University, Lublin, Poland. jjgil@biotop.umcs.lublin.pl
authors.forename: Joanna
authors.initials: J
authors.lastname: Jakubowicz-Gil
authors.forename: Bozena
authors.initials: B
authors.lastname: Pawlikowska-Pawlega
authors.forename: Tomasz
authors.initials: T
authors.lastname: Piersiak
authors.forename: Jarosław
authors.initials: J
authors.lastname: Pawelec
authors.forename: Antoni
authors.initials: A
authors.lastname: Gawron
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D002467:Cell Nucleus / Q000187:drug effects* / Q000378:metabolism; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism*; D006367:HeLa Cells; D018869:Heat-Shock Response / Q000187:drug effects* / Q000502:physiology*; D006358:Hot Temperature; D006801:Humans; D011794:Quercetin / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D050884:HSP72 Heat-Shock Proteins; D011794:Quercetin