title: HSF1 granules: a novel stress-induced nuclear compartment of human cells.
abstract: Heat shock factor 1 (HSF1) is the ubiquitous stress-responsive transcriptional activator which is essential for the inducible transcription of genes encoding heat shock proteins and molecular chaperones. HSF1 localizes within the nucleus of cells exposed to heat shock, heavy metals, and amino acid analogues, to form large, irregularly shaped, brightly staining granules which are not detected during attenuation of the heat shock response or when cells are returned to their normal growth conditions. The kinetics of detection of HSF1 granules parallels the transient induction of heat shock gene transcription. HSF1 granules are also detected using an HSF1-Flag epitope tagged protein or a chimeric HSF1-green fluorescent protein which reveals that these nuclear structures are stress-induced and can be detected in living cells. The spatial organization of HSF1 granules in nuclei of stressed cells reveals that they are novel nuclear structures which are stress-dependent and provides evidence that the nucleus undergoes dynamic reorganization in response to stress.
authors.affiliation: Department of Biochemistry, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA.
authors.forename: J
authors.initials: J
authors.lastname: Cotto
authors.forename: S
authors.initials: S
authors.lastname: Fox
authors.forename: R
authors.initials: R
authors.lastname: Morimoto
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D001384:Azetidines / Q000494:pharmacology; D019187:Cadmium Compounds / Q000494:pharmacology; D002460:Cell Line; D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure*; D004268:DNA-Binding Proteins / Q000032:analysis / Q000096:biosynthesis*; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D006358:Hot Temperature; D006801:Humans; D002479:Inclusion Bodies / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D012459:Salicylates / Q000494:pharmacology; D020156:Salicylic Acid; D013431:Sulfates / Q000494:pharmacology; D015534:Trans-Activators / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis
chemical_list: D000596:Amino Acids; D001384:Azetidines; D019187:Cadmium Compounds; D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D012459:Salicylates; D013431:Sulfates; D015534:Trans-Activators; D014157:Transcription Factors; C082735:azetidine; C037123:cadmium sulfate; D020156:Salicylic Acid