scholarly journals Stress-induced transcription of satellite III repeats

2003 ◽  
Vol 164 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Caroline Jolly ◽  
Alexandra Metz ◽  
Jérôme Govin ◽  
Marc Vigneron ◽  
Bryan M. Turner ◽  
...  
Keyword(s):  
Heat Shock ◽  
Rna Polymerase Ii ◽  
Mammalian Cells ◽  
Stress Granules ◽  
Transcription Sites ◽  
Direct Binding ◽  
Nuclear Structures ◽  
Hsp Genes ◽  
Transcription Factor 1 ◽  
Rna Polymerase Ii Transcription

Exposure of mammalian cells to stress induces the activation of heat shock transcription factor 1 (HSF1) and the subsequent transcription of heat shock genes. Activation of the heat shock response also correlates with a rapid relocalization of HSF1 within a few nuclear structures termed nuclear stress granules. These stress-induced structures, which form primarily on the 9q12 region in humans through direct binding of HSF1 to satellite III repeats, do not colocalize with transcription sites of known hsp genes. In this paper, we show that nuclear stress granules correspond to RNA polymerase II transcription factories where satellite III repeats are transcribed into large and stable RNAs that remain associated with the 9q12 region, even throughout mitosis. This work not only reveals the existence of a new major heat-induced transcript in human cells that may play a role in chromatin structure, but also provides evidence for a transcriptional activity within a locus considered so far as heterochromatic and silent.

Gcn5- and Elp3-induced histone H3 acetylation regulates hsp70 gene transcription in yeast

2008 ◽  
Vol 409 (3) ◽  
pp. 779-788 ◽  
Author(s):  
Qiuju Han ◽  
Jun Lu ◽  
Jizhou Duan ◽  
Dongmei Su ◽  
Xiaozhe Hou ◽  
...  
Keyword(s):  
Heat Shock ◽  
Histone Acetylation ◽  
Rna Polymerase Ii ◽  
Gene Transcription ◽  
Transcriptional Activation ◽  
Histone H3 ◽  
Hsp70 Gene ◽  
Transcriptional Initiation ◽  
Hsp Genes ◽  
H3 Acetylation

The purpose of this study was to elucidate the mechanisms by which histone acetylation participates in transcriptional regulation of hsp70 (heat-shock protein 70) genes SSA3 and SSA4 in yeast. Our results indicated that histone acetylation was required for the transcriptional activation of SSA3 and SSA4. The HATs (histone acetyltransferases) Gcn5 (general control non-derepressible 5) and Elp3 (elongation protein 3) modulated hsp70 gene transcription by affecting the acetylation status of histone H3. Although the two HATs possessed overlapping function regarding the acetylation of histone H3, they affected hsp70 gene transcription in different ways. The recruitment of Gcn5 was Swi/Snf-dependent and was required for HSF (heat-shock factor) binding and affected RNAPII (RNA polymerase II) recruitment, whereas Elp3 exerted its roles mainly through affecting RNAPII elongation. These results provide insights into the effects of Gcn5 and Elp3 in hsp70 gene transcription and underscore the importance of histone acetylation for transcriptional initiation and elongation in hsp genes.

scholarly journals The translation elongation factor eEF1A1 couples transcription to translation during heat shock response

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Maria Vera ◽  
Bibhusita Pani ◽  
Lowri A Griffiths ◽  
Christian Muchardt ◽  
Catherine M Abbott ◽  
...  
Keyword(s):  
Heat Shock ◽  
Rna Polymerase Ii ◽  
Heat Shock Response ◽  
Mammalian Cells ◽  
Elongation Factor ◽  
Translation Elongation Factor ◽  
Translation Elongation ◽  
Hsp70 Mrna ◽  
Shock Response ◽  
Attractive Therapeutic Target

Translation elongation factor eEF1A has a well-defined role in protein synthesis. In this study, we demonstrate a new role for eEF1A: it participates in the entire process of the heat shock response (HSR) in mammalian cells from transcription through translation. Upon stress, isoform 1 of eEF1A rapidly activates transcription of HSP70 by recruiting the master regulator HSF1 to its promoter. eEF1A1 then associates with elongating RNA polymerase II and the 3′UTR of HSP70 mRNA, stabilizing it and facilitating its transport from the nucleus to active ribosomes. eEF1A1-depleted cells exhibit severely impaired HSR and compromised thermotolerance. In contrast, tissue-specific isoform 2 of eEF1A does not support HSR. By adjusting transcriptional yield to translational needs, eEF1A1 renders HSR rapid, robust, and highly selective; thus, representing an attractive therapeutic target for numerous conditions associated with disrupted protein homeostasis, ranging from neurodegeneration to cancer.

scholarly journals The Role of Heat Shock Transcription Factor 1 in the Genome-wide Regulation of the Mammalian Heat Shock Response

2004 ◽  
Vol 15 (3) ◽  
pp. 1254-1261 ◽  
Author(s):  
Nathan D. Trinklein ◽  
John I. Murray ◽  
Sara J. Hartman ◽  
David Botstein ◽  
Richard M. Myers
Keyword(s):  
Transcription Factor ◽  
Heat Shock ◽  
Heat Shock Response ◽  
Mammalian Cells ◽  
Transcriptional Response ◽  
Heat Shock Transcription Factor ◽  
Genome Wide ◽  
Shock Response ◽  
Inducible Genes ◽  
Transcription Factor 1

Previous work has implicated heat shock transcription factor 1 (HSF1) as the primary transcription factor responsible for the transcriptional response to heat stress in mammalian cells. We characterized the heat shock response of mammalian cells by measuring changes in transcript levels and assaying binding of HSF1 to promoter regions for candidate heat shock genes chosen by a combination of genome-wide computational and experimental methods. We found that many heat-inducible genes have HSF1 binding sites (heat shock elements, HSEs) in their promoters that are bound by HSF1. Surprisingly, for 24 heat-inducible genes, we detected no HSEs and no HSF1 binding. Furthermore, of 182 promoters with likely HSE sequences, we detected HSF1 binding at only 94 of these promoters. Also unexpectedly, we found 48 genes with HSEs in their promoters that are bound by HSF1 but that nevertheless did not show induction after heat shock in the cell types we examined. We also studied the transcriptional response to heat shock in fibroblasts from mice lacking the HSF1 gene. We found 36 genes in these cells that are induced by heat as well as they are in wild-type cells. These results provide evidence that HSF1 does not regulate the induction of every transcript that accumulates after heat shock, and our results suggest that an independent posttranscriptional mechanism regulates the accumulation of a significant number of transcripts.

scholarly journals Signal Transduction Pathways Leading to Heat Shock Transcription

2010 ◽  
Vol 2 ◽  
pp. STI.S3994 ◽  
Author(s):  
S. K. Calderwood ◽  
Y. Wang ◽  
X. Xie ◽  
M. A Khaleque ◽  
S. D Chou ◽  
...  
Keyword(s):  
Heat Shock ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Feedback Inhibition ◽  
Open Reading Frames ◽  
Transcriptional Level ◽  
Transcriptional Initiation ◽  
Nucleosome Remodeling ◽  
Shock Proteins ◽  
Hsp Genes

Heat shock proteins (HSP) are essential for intracellular protein folding during stress and protect cells from denaturation and aggregation cascades that can lead to cell death. HSP genes are regulated at the transcriptional level by heat shock transcription factor 1 (HSF1) that is activated by stress and binds to heat shock elements in HSP genes. The activation of HSF1 during heat shock involves conversion from an inert monomer to a DNA binding trimer through a series of intramolecular folding rearrangements. However, the trigger for HSF1 at the molecular level is unclear and hypotheses for this process include reversal of feedback inhibition of HSF1 by molecular chaperones and heat-induced binding to large non-coding RNAs. Heat shock also causes a profound modulation in cell signaling pathways that lead to protein kinase activation and phosphorylation of HSF1 at a number of regulatory serine residues. HSP genes themselves exist in an accessible chromatin conformation already bound to RNA polymerase II. The RNA polymerase II is paused on HSP promoters after transcribing a short RNA sequence proximal to the promoter. Activation by heat shock involves HSF1 binding to the promoter and release of the paused RNA polymerase II followed by further rounds of transcriptional initiation and elongation. HSF1 is thus involved in both initiation and elongation of HSP RNA transcripts. Recent studies indicate important roles for histone modifications on HSP genes during heat shock. Histone modification occurs rapidly after stress and may be involved in promoting nucleosome remodeling on HSP promoters and in the open reading frames of HSP genes. Understanding these processes may be key to evaluating mechanisms of deregulated HSP expression that plays a key role in neurodegeneration and cancer.

scholarly journals Distinct properties of c-myc transcriptional elongation are revealed in Xenopus oocytes and mammalian cells and by template titration, 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), and promoter mutagenesis.

1993 ◽  
Vol 13 (9) ◽  
pp. 5647-5658 ◽  
Author(s):  
T Meulia ◽  
A Krumm ◽  
M Groudine
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Initiation ◽  
Mammalian Cells ◽  
Xenopus Oocytes ◽  
Premature Termination ◽  
Proximal Region ◽  
Transcriptional Elongation ◽  
Transcription Complexes ◽  
Rna Polymerase Ii Transcription

A block to c-myc transcription elongation has been observed in Xenopus oocytes and mammalian cells. Here, we show that the distribution of RNA polymerase II transcription complexes in the c-myc promoter proximal region in Xenopus oocytes is different from that observed previously in mammalian cells. Thus, there are major differences in the c-myc elongation block observed in the two systems. In addition, as first reported for a Xenopus tubulin gene (K. M. Middleton and G. T. Morgan, Mol. Cell. Biol. 10:727-735, 1990). c-myc template titration experiments reveal the existence of two classes of RNA polymerase II transcription complexes in oocytes: one (at low template concentration) that is capable of reading through downstream sites of premature termination, and another (high template concentration) that does not. We show that these classes of polymerases are distinct from those previously identified by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), which distinguishes transcription complexes on the basis of transcribed distance, rather than on the basis of differential elongation through sites of premature termination. We also show that mutations that affect the efficiency of initiation of transcription from the c-myc P2 promoter can influence premature termination by at least two mechanisms: TATA box mutations function by the titration effect (decrease in transcription initiation results in a relative decrease in premature termination), while an upstream activator (E2F) site functions by contributing to the assembly of polymerase complexes competent to traverse the downstream sites of premature termination.

scholarly journals Hypophosphorylated SR splicing factors transiently localize around active nucleolar organizing regions in telophase daughter nuclei

2004 ◽  
Vol 167 (1) ◽  
pp. 51-63 ◽  
Author(s):  
Paula A. Bubulya ◽  
Kannanganattu V. Prasanth ◽  
Thomas J. Deerinck ◽  
Daniel Gerlich ◽  
Joel Beaudouin ◽  
...  
Keyword(s):  
Rna Polymerase Ii ◽  
Sr Proteins ◽  
Splicing Factors ◽  
Nuclear Speckles ◽  
Sr Protein ◽  
Nucleolar Organizing Regions ◽  
Transcription Sites ◽  
Nuclear Regions ◽  
Rna Polymerase Ii Transcription

Upon completion of mitosis, daughter nuclei assemble all of the organelles necessary for the implementation of nuclear functions. We found that upon entry into daughter nuclei, snRNPs and SR proteins do not immediately colocalize in nuclear speckles. SR proteins accumulated in patches around active nucleolar organizing regions (NORs) that we refer to as NOR-associated patches (NAPs), whereas snRNPs were enriched at other nuclear regions. NAPs formed transiently, persisting for 15–20 min before dissipating as nuclear speckles began to form in G1. In the absence of RNA polymerase II transcription, NAPs increased in size and persisted for at least 2 h, with delayed localization of SR proteins to nuclear speckles. In addition, SR proteins in NAPs are hypophosphorylated, and the SR protein kinase Clk/STY colocalizes with SR proteins in NAPs, suggesting that phosphorylation releases SR proteins from NAPs and their initial target is transcription sites. This work demonstrates a previously unrecognized role of NAPs in splicing factor trafficking and nuclear speckle biogenesis.

HSF1 transcription factor concentrates in nuclear foci during heat shock: relationship with transcription sites

1997 ◽  
Vol 110 (23) ◽  
pp. 2935-2941 ◽  
Author(s):  
C. Jolly ◽  
R. Morimoto ◽  
M. Robert-Nicoud ◽  
C. Vourc'h
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
In Situ Hybridization ◽  
Heat Shock ◽  
Human Fibroblasts ◽  
Relative Distribution ◽  
Transcription Sites ◽  
Nuclear Foci ◽  
Hsp Genes

In this paper, we show that upon heat shock, HSF1 concentrates in the nucleus of diploid human fibroblasts in two large foci. The relative distribution of HSF1 nuclear foci and active heat shock protein (hsp) genes was investigated by combining fluorescence in situ hybridization (FISH) for the detection of hsp nuclear transcripts and immunofluorescence for the detection of HSF1. We show that the HSF1 foci are distinct from the sites of hsp70 and hsp90 genes transcription. This is the second report of ploidy-dependent foci of transcription factors that are independent of their specific transcription sites. However, the correlation between the number of HSF1 foci and the ploidy of the cells strongly supports the existence of a specific chromosomal target for HSF1 foci.

scholarly journals PARP1 promotes the human heat shock response by facilitating HSF1 binding to DNA

2018 ◽  
pp. MCB.00051-18 ◽  
Author(s):  
Mitsuaki Fujimoto ◽  
Ryosuke Takii ◽  
Arpit Katiyar ◽  
Pratibha Srivastava ◽  
Akira Nakai
Keyword(s):  
Transcription Factor ◽  
Heat Shock ◽  
Heat Shock Response ◽  
Mammalian Cells ◽  
Ternary Complex ◽  
Regulatory Mechanisms ◽  
Gene Body ◽  
Shock Response ◽  
Shock Proteins ◽  
Transcription Factor 1

The heat shock response (HSR) is characterized by the rapid and robust induction of heat shock proteins (HSPs), including HSP70, in response to heat shock, and is regulated by heat shock transcription factor 1 (HSF1) in mammalian cells. Poly(ADP-ribose) polymerase 1 (PARP1), which can form a complex with HSF1 through the scaffold protein PARP13, has been suggested to be involved in the HSR. However, its effects on and regulatory mechanisms of the HSR are not well understood. Here, we show that prior to heat shock the HSF1-PARP13-PARP1 complex binds to HSP70 promoter. In response to heat shock, activated and auto-PARylated PARP1 dissociates from HSF1-PARP13 and redistributes throughout HSP70 locus. Remarkably, chromatin in HSP70 promoter is initially PARylated at high levels and decondensed, whereas that in the gene body is moderately PARylated afterwards. Activated HSF1 then binds to the promoter efficiently, and promotes the HSR. Chromatin PARylation and HSF1 binding to the promoter are also facilitated by phosphorylation-dependent dissociation of PARP13. Furthermore, the HSR and proteostasis capacity are reduced by pretreatment with genotoxic stresses, which disrupt the ternary complex. These results provide one of the priming mechanisms of the HSR that facilitates HSF1 binding to DNA during heat shock.

Distinct properties of c-myc transcriptional elongation are revealed in Xenopus oocytes and mammalian cells and by template titration, 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), and promoter mutagenesis

1993 ◽  
Vol 13 (9) ◽  
pp. 5647-5658
Author(s):  
T Meulia ◽  
A Krumm ◽  
M Groudine
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Initiation ◽  
Mammalian Cells ◽  
Xenopus Oocytes ◽  
Premature Termination ◽  
Proximal Region ◽  
Transcriptional Elongation ◽  
Transcription Complexes ◽  
Rna Polymerase Ii Transcription

A block to c-myc transcription elongation has been observed in Xenopus oocytes and mammalian cells. Here, we show that the distribution of RNA polymerase II transcription complexes in the c-myc promoter proximal region in Xenopus oocytes is different from that observed previously in mammalian cells. Thus, there are major differences in the c-myc elongation block observed in the two systems. In addition, as first reported for a Xenopus tubulin gene (K. M. Middleton and G. T. Morgan, Mol. Cell. Biol. 10:727-735, 1990). c-myc template titration experiments reveal the existence of two classes of RNA polymerase II transcription complexes in oocytes: one (at low template concentration) that is capable of reading through downstream sites of premature termination, and another (high template concentration) that does not. We show that these classes of polymerases are distinct from those previously identified by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), which distinguishes transcription complexes on the basis of transcribed distance, rather than on the basis of differential elongation through sites of premature termination. We also show that mutations that affect the efficiency of initiation of transcription from the c-myc P2 promoter can influence premature termination by at least two mechanisms: TATA box mutations function by the titration effect (decrease in transcription initiation results in a relative decrease in premature termination), while an upstream activator (E2F) site functions by contributing to the assembly of polymerase complexes competent to traverse the downstream sites of premature termination.

Sign in / Sign up

Export Citation Format

Share Document