In vivo binding of active heat shock transcription factor 1 to human chromosome 9 heterochromatin during stress.
Activation of the mammalian heat shock transcription factor (HSF)1 by stress is a multistep process resulting in the transcription of heat shock genes. Coincident with these events is the rapid and reversible redistribution of HSF1 to discrete nuclear structures termed HSF1 granules, whose function is still unknown. Key features are that the number of granules correlates with cell ploidy, suggesting the existence of a chromosomal target. Here we show that in humans, HSF1 granules localize to the 9q11-q12 heterochromatic region. Within this locus, HSF1 binds through direct DNA-protein interaction with a nucleosome-containing subclass of satellite III repeats. HSF1 granule formation only requires the DNA binding competence and the trimerization of the factor. This is the first example of a transcriptional activator that accumulates transiently and reversibly on a chromosome-specific heterochromatic locus.
Jolly
Caroline
C
DyOGen, INSERM U309, Institut A. Bonniot, Domaine de la Merci, 38706 La Tronche cedex, France. caroline.jolly@ujf-grenoble.fr
Konecny
Lara
L
Grady
Deborah L
DL
Kutskova
Yulia A
YA
Cotto
Jose J
JJ
Morimoto
Richard I
RI
Vourc'h
Claire
C
D001665:Binding Sites / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D003594:Cytoplasmic Granules / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006570:Heterochromatin / Q000235:genetics*; D006801:Humans; D018895:Microsatellite Repeats / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics; D013312:Stress, Physiological / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors
D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins; D006570:Heterochromatin; D014157:Transcription Factors