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. 2007 Autumn;12(3):283-90.
doi: 10.1379/csc-250.1.

HSF2 binds to the Hsp90, Hsp27, and c-Fos promoters constitutively and modulates their expression

Donald C Wilkerson  1 , Hollie S Skaggs, Kevin D Sarge
Affiliations

HSF2 binds to the Hsp90, Hsp27, and c-Fos promoters constitutively and modulates their expression

Donald C Wilkerson et al. Cell Stress Chaperones. 2007 Autumn.

Abstract

Although the vast majority of genomic DNA is tightly compacted during mitosis, the promoter regions of a number of genes remain in a less compacted state throughout this stage of the cell cycle. The decreased compaction of these promoter regions, which is referred to as gene bookmarking, is thought to be important for the ability of cells to express these genes during the following interphase. Previously, we reported a role for the DNA-binding protein heat shock factor (HSF2) in bookmarking the stress-inducible 70,000-Da heat shock protein (hsp70) gene. In this report, we have extended those studies and found that during mitosis, HSF2 is bound to the HSE promoter elements of other heat shock genes, including hsp90 and hsp27, as well as the proto-oncogene c-fos. The presence of HSF2 is important for expression of these genes because blocking HSF2 levels by RNA interference techniques leads to decreased levels of these proteins. These results suggest that HSF2 is important for constitutive as well as stress-inducible expression of HSE-containing genes.

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Figures

Fig 1.
Fig 1.
Schematic diagram of the proximal promoters of HSE-containing genes. The proximal promoter regions of the hsp27, hsp70, hsp90, and c-fos genes are shown with the position of the HSE promoter elements labeled relative to the transcription initiation start site (+1). Arrows represent the binding sites for primers used to analyze DNA obtained with chromatin immunoprecipitation assays
Fig 2.
Fig 2.
Increased mitotic binding of HSF2 but not RNA polymerase II to HSE promoters. (A) Chromatin immunoprecipitation (ChIP) assays were performed with either HSF2 antibodies or nonspecific antibodies (as negative controls) and analyzed by polymerase chain reaction (PCR) with primers that amplify promoter regions of the hsp70, hsp27, hsp90, H2B, and DHFR genes. The top panel for each gene represents a PCR reaction with the use of HSF2-precipitated DNA fragments obtained from an asynchronous or mitotic (nocodazole treated) population of Jurkat cells. The middle panels represent PCR reactions with nonspecific rabbit immunoglobulin (IgG)-precipitated DNA fragments as template from asynchronous and mitotic populations of Jurkat cells. The lower panels represent PCR reactions with template DNA that was treated in the same manner as the HSF2- and IgG-precipitated DNA, except the input DNA was not subjected to immunoprecipitation. (B) ChIP assays with RNA polymerase II antibodies were performed as above and analyzed by PCR with primers that amplify promoter regions of the hsp70, hsp90, and c-fos genes
Fig 3.
Fig 3.
Inhibiting HSF2 expression decreases expression of hsp90 and hsp27. Asynchronous populations of HeLa cells were transfected with HSF2-specific or scrambled small interfering RNA (siRNA), and then extracts of these cells were subjected to sodium dodecyl sulfate–polyacrylamide gel electrophoresis and Western blot analysis with antibodies against HSF2 and HSF1 (A) or against Hsp27, Hsp90, or β-actin (B)
Fig 4.
Fig 4.
HSF2 binds the HSE-containing promoter of the c-fos gene in mitotic cells and is important for expression of this gene. (A) The results of polymerase chain reaction (PCR) with chromatin immunoprecipitation (ChIP) DNA immunoprecipitated with c-Fos and H4 antibodies. The panels for each gene represent PCR reactions carried out as labeled in Figure 2, with the top panel representing HSF2-precipitated DNA fragments used as PCR template, the middle panels representing rabbit immunoglobulin (IgG)-precipitated DNA fragments as template, and the lower panels representing mock-treated template DNA. (B) An asynchronous population of HeLa cells were treated with HSF2-specific or scrambled small interfering RNA (siRNA), and the effect on c-Fos protein levels was assayed by Western blots with c-Fos antibodies. A Western blot with antibodies against β-actin was performed as a loading control
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References

    1. Abravaya K, Phillips B, Morimoto RI. Heat shock-induced interactions of heat shock transcription factor and the human hsp70 promoter examined by in vivo footprinting. Mol Cell Biol. 1991;11:586–592.1098-5549(1991)011[0586:HSIOHS]2.0.CO;2 - PMC - PubMed
    1. Christova R, Oelgeschlager T. Association of human TFIID– promoter complexes with silenced mitotic chromatin in vivo. Nat Cell Biol. 2002;4:79–82.1465-7392(2002)004[0079:AOHTPC]2.0.CO;2 - PubMed
    1. Ciocca DR, Adams DJ, Bjercke RJ, Edwards DP, McGuire WL. Immunohistochemical detection of an estrogen-regulated protein by monoclonal antibodies. Cancer Res. 1982;42:4256–4258.0008-5472(1982)042[4256:IDOAEP]2.0.CO;2 - PubMed
    1. Ciocca DR, Adams DJ, Edwards DP, Bjercke RJ, McGuire WL. Distribution of an estrogen-induced protein with a molecular weight of 24,000 in normal and malignant human tissues and cells. Cancer Res. 1983;43:1204–1210.0008-5472(1983)043[1204:DOAEPW]2.0.CO;2 - PubMed
    1. Ciocca DR, Calderwood SK. Heat shock proteins in cancer: diagnostic, prognostic, predictive, and treatment implications. Cell Stress Chaperones. 2005;10:86–103.1466-1268(2005)010[0086:HSPICD]2.0.CO;2 - PMC - PubMed

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