Transcriptional regulation and binding of heat shock factor 1 and heat shock factor 2 to 32 human heat shock genes during thermal stress and differentiation - PubMed (original) (raw)

Transcriptional regulation and binding of heat shock factor 1 and heat shock factor 2 to 32 human heat shock genes during thermal stress and differentiation

Nathan D Trinklein et al. Cell Stress Chaperones. 2004 Mar.

Abstract

Transcription of mammalian heat shock genes can be regulated by heat shock factors (HSF) 1 and 2. Although it has been shown previously that these factors respond to distinct stimuli, a broad analysis of the induction and function of these factors in living cells has not been performed. In our study, we assayed binding of human HSF1 and HSF2 at the promoters of 32 genes identified through LocusLink as heat shock genes in response to elevated temperature and hemin-induced differentiation in human K562 erythroleukemic cells using the chromatin immunoprecipitation technique. We also measured the induced expression of these genes under these 2 conditions. We found that 17 of the 32 genes were transcriptionally induced during heat shock, and HSF1 binding was detected at 15 of the 17 promoters. Nearly all the genes induced by heat shock were also induced to a lesser degree during hemin treatment. However, some genes were induced significantly more during hemin treatment than during heat shock. A new finding is that HSF1 and HSF2 bind to the same targets, but HSF1 binding is activated more by heat than by hemin treatment, and HSF2 binding is only activated by hemin treatment and not by heat. This technology also identified previously unknown HSF1 binding sites near genes that were previously shown to be heat inducible that may contribute to gene-specific regulation.

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Figures

Fig 1.

Fig 1.

Heat shock and hemin-induced gene expression patterns. The expression data for 32 genes during heat shock and hemin-induced differentiation show that many of the same genes are induced during heat shock and hemin treatment. Time points are listed at the top of the figure. The number of vertical bars in each box indicate the fold-induction of a given gene at that time point according to the key at the bottom of the figure

Fig 2.

Fig 2.

Expression kinetics of 6 genes during heat shock and differentiation. Each panel displays the expression kinetics of a single gene during heat shock and hemin-induced differentiation. Fold-induction is shown in log scale on the y-axis for each panel. Time points for heat shock and differentiation are shown on the x-axis at the bottom of the graph

Fig 3.

Fig 3.

HSF1 and HSF2 binding during heat shock and differentiation. (A) The bars indicate the degree of HSF1 and HSF2 binding to each promoter. Binding was quantitated by the ChIP fold-enrichment of each gene's promoter, which is shown on the scale on the left of the y-axis. Solid bars are from the heat shock HSF1 ChIP, and hatched bars are from the heat shock HSF2 ChIP. Both ChIPs were done 1 hour after heat shock. The white diamonds indicate the fold-induced expression at the 2-hour recovery time point after heat shock. Fold-induced expression values are shown on the right of the y-axis. (B) Same as panel A, except binding was assayed by ChIP 24 hours after the addition of hemin, and the diamonds indicate the fold-induced expression at the 72-hour time point of hemin treatment. HSF, heat shock factor; ChIP, chromatin immunoprecipitation

Fig 4.

Fig 4.

Reciprocal binding of HSF1 and HSF2 during heat shock and differentiation. Binding was quantitated in both panels by the ChIP fold-enrichment of each gene's promoter. Fold-enrichment is shown on the y-axis. (A) The white and black bars show HSF1 binding during heat shock and hemin treatment, respectively. (B) The white and black bars show HSF2 binding during heat shock and hemin treatment, respectively. ChIP, chromatin immunoprecipitation

Fig 5.

Fig 5.

HSF1 binding throughout the genomic regions of 5 heat shock genes. We assayed HSF1 binding at regularly spaced intervals throughout 3 genomic regions that contain 5 heat shock genes. Amplicons were designed to assay binding in the genomic regions of hsp27.1 (panel A), hsp90-β (panel B), and the region including hsp70-A1A, A1B, and A1L (panel C). White diamonds indicate HSE, and the sequence is shown for each. The enrichment of each amplicon is shown on the y-axis. HSF, heat shock factor; HSE, heat shock element

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References

    1. Kallio M, Chang Y, and Manuel M. et al. 2002 Brain abnormalities, defective meiotic chromosome synapsis and female subfertility in HSF2 null mice. EMBO J. 21:2591–2601. - PMC - PubMed
    1. Lam LT, Ronchini C, Norton J, Capobianco AJ, Bresnick EH. Suppression of erythroid but not megakaryocytic differentiation of human K562 erythroleukemic cells by notch-1. J Biol Chem. 2000;275:19676–19684.0021-9258(2000)275<19676:SOEBNM>2.0.CO;2 - PubMed
    1. Leppa S, Pirkkala L, Chow SC, Eriksson JE, Sistonen L. Thioredoxin is transcriptionally induced upon activation of heat shock factor 2. J Biol Chem. 1997;28:30400–30404.0021-9258(1997)028<30400:TITIUA>2.0.CO;2 - PubMed
    1. Mathew A, Mathur SK, Jolly C, Fox SG, Kim S, Morimoto RI. Stress-specific activation and repression of heat shock factors 1 and 2. Mol Cell Biol. 2001;21:7163–7171.0270-7306(2001)021<7163:SAAROH>2.0.CO;2 - PMC - PubMed
    1. Mathew A, Mathur SK, Morimoto RI. Heat shock response and protein degradation: regulation of HSF2 by the ubiquitin-proteasome pathway. Mol Cell Biol. 1998;18:5091–5098.0270-7306(1998)018<5091:HSRAPD>2.0.CO;2 - PMC - PubMed

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