Repression of hsp70 heat shock gene transcription by the suppressor of hairy-wing protein of Drosophila melanogaster

1991 ◽  
Vol 11 (4) ◽  
pp. 1894-1900
Author(s):  
C Holdridge ◽  
D Dorsett
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Protein Binding ◽  
Protein Interactions ◽  
Binding Sites ◽  
Zinc Finger Protein ◽  
Gene Promoter ◽  
Heat Shock Gene ◽  
Protein Binding Sites ◽  
Shock Gene

The suppressor of hairy-wing [su(Hw)] locus of Drosophila melanogaster encodes a zinc finger protein that binds a repeated motif in the gypsy retroposon. Mutations of su(Hw) suppress the phenotypes associated with mutations caused by gypsy insertions. To examine the mechanisms by which su(Hw) alters gene expression, a fragment of gypsy containing multiple su(Hw) protein-binding sites was inserted into various locations in the well-characterized Drosophila hsp70 heat shock gene promoter. We found no evidence for activation of basal hsp70 transcription by su(Hw) protein in cultured Drosophila cells but observed that it can repress heat shock-induced transcription. Repression occurred only when su(Hw) protein-binding sites were positioned between binding sites for proteins required for heat shock transcription. We propose that su(Hw) protein interferes nonspecifically with protein-protein interactions required for heat shock transcription, perhaps sterically, or by altering the ability of DNA to bend or twist.

scholarly journals Repression of hsp70 heat shock gene transcription by the suppressor of hairy-wing protein of Drosophila melanogaster.

1991 ◽  
Vol 11 (4) ◽  
pp. 1894-1900 ◽  
Author(s):  
C Holdridge ◽  
D Dorsett
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Protein Binding ◽  
Protein Interactions ◽  
Binding Sites ◽  
Zinc Finger Protein ◽  
Gene Promoter ◽  
Heat Shock Gene ◽  
Protein Binding Sites ◽  
Shock Gene

The suppressor of hairy-wing [su(Hw)] locus of Drosophila melanogaster encodes a zinc finger protein that binds a repeated motif in the gypsy retroposon. Mutations of su(Hw) suppress the phenotypes associated with mutations caused by gypsy insertions. To examine the mechanisms by which su(Hw) alters gene expression, a fragment of gypsy containing multiple su(Hw) protein-binding sites was inserted into various locations in the well-characterized Drosophila hsp70 heat shock gene promoter. We found no evidence for activation of basal hsp70 transcription by su(Hw) protein in cultured Drosophila cells but observed that it can repress heat shock-induced transcription. Repression occurred only when su(Hw) protein-binding sites were positioned between binding sites for proteins required for heat shock transcription. We propose that su(Hw) protein interferes nonspecifically with protein-protein interactions required for heat shock transcription, perhaps sterically, or by altering the ability of DNA to bend or twist.

scholarly journals Sequences involved in temperature and ecdysterone-induced transcription are located in separate regions of a Drosophila melanogaster heat shock gene.

1986 ◽  
Vol 6 (2) ◽  
pp. 663-673 ◽  
Author(s):  
E Hoffman ◽  
V Corces
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Dna Sequences ◽  
Germ Line ◽  
Initiation Site ◽  
P Element ◽  
Heat Shock Gene ◽  
Base Pairs ◽  
Consensus Sequences ◽  
Shock Gene

The transcriptional regulation of the Drosophila melanogaster hsp27 (also called hsp28) gene was studied by introducing altered genes into the germ line by P element-mediated transformation. DNA sequences upstream of the gene were defined with respect to their effect on steroid hormone-induced and heat-induced transcription. These two types of control were found to be separable; the sequences responsible for 80% of heat-induced expression were located more than 1.1 kilobases upstream of the RNA initiation site, while the sequences responsible for the majority of ecdysterone induction were positioned downstream of the site at -227 base pairs. We have determined the DNA sequence of the intergenic region separating hsp23 and hsp27 and have located putative heat shock and ecdysterone consensus sequences. Our results indicate that the heat shock promoter of the hsp27 gene is organized quite differently from that of hsp70.

Deletion polymorphism in a Drosophila melanogaster heat shock gene

1986 ◽  
Vol 204 (2) ◽  
pp. 266-272 ◽  
Author(s):  
Karl Sirotkin ◽  
Nancy Bartley ◽  
William L. Perry ◽  
Douglas Briggs ◽  
Ed H. Grell ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Heat Shock Gene ◽  
Deletion Polymorphism ◽  
Shock Gene

Conditional silencing: the HMRE mating-type silencer exerts a rapidly reversible position effect on the yeast HSP82 heat shock gene

1993 ◽  
Vol 13 (2) ◽  
pp. 727-738
Author(s):  
S Lee ◽  
D S Gross
Keyword(s):  
Heat Shock ◽  
Mating Type ◽  
Binding Sites ◽  
Position Effect ◽  
Heat Shock Factor ◽  
Heat Shock Gene ◽  
Autonomously Replicating Sequence ◽  
Type Locus ◽  
Factor Binding ◽  
Shock Gene

The HMRE silencer of Saccharomyces cerevisiae has been previously shown to transcriptionally repress class II and class III genes integrated within the HMR silent mating-type locus up to 2.6 kb away. Here we study the ability of this element to repress at an ectopic position, independent of sequences normally associated with it. When integrated 750 bp upstream of the HSP82 heat shock gene, the silencer represses basal-level transcription approximately 5-fold but has no effect on chemical- or heat-shock-induced expression. Such conditional silencing is also seen when the HMRE/HSP82 allele is carried on a centromeric episome or when the entire HMRa domain is transplaced 2.7 kb upstream of HSP82. Notably, the a1 promoter within the immigrant HMRa locus remains fully repressed at the same time HSP82 is derepressed. The position effect mediated by the E silencer is absolutely dependent on the presence of a functional SIR4 gene product, is lost within 1 min following stress induction, and is fully reestablished within 15 min following a return to nonstressful conditions. Similar kinetics of reestablishment are seen in HMRE/HSP82 and HMRa/HSP82 strains, indicating that complete repression can be mediated over thousands of base pairs within minutes. DNase I chromatin mapping reveals that the ABF1, RAP1, and autonomously replicating sequence factor binding sites within the silencer are constitutively occupied in chromatin, unaltered by heat shock or the presence of SIR4. Similarly, the heat shock factor binding site upstream of HSP82 remains occupied under such conditions, suggesting concurrent occupancy of silencer and activator binding sites. Our results are consistent with a model in which silencing at the HMRE/HSP82 allele is mediated by direct or indirect contacts between the silencer protein complex and heat shock factor.

scholarly journals Conditional silencing: the HMRE mating-type silencer exerts a rapidly reversible position effect on the yeast HSP82 heat shock gene.

1993 ◽  
Vol 13 (2) ◽  
pp. 727-738 ◽  
Author(s):  
S Lee ◽  
D S Gross
Keyword(s):  
Heat Shock ◽  
Mating Type ◽  
Binding Sites ◽  
Position Effect ◽  
Heat Shock Factor ◽  
Heat Shock Gene ◽  
Autonomously Replicating Sequence ◽  
Type Locus ◽  
Factor Binding ◽  
Shock Gene

The HMRE silencer of Saccharomyces cerevisiae has been previously shown to transcriptionally repress class II and class III genes integrated within the HMR silent mating-type locus up to 2.6 kb away. Here we study the ability of this element to repress at an ectopic position, independent of sequences normally associated with it. When integrated 750 bp upstream of the HSP82 heat shock gene, the silencer represses basal-level transcription approximately 5-fold but has no effect on chemical- or heat-shock-induced expression. Such conditional silencing is also seen when the HMRE/HSP82 allele is carried on a centromeric episome or when the entire HMRa domain is transplaced 2.7 kb upstream of HSP82. Notably, the a1 promoter within the immigrant HMRa locus remains fully repressed at the same time HSP82 is derepressed. The position effect mediated by the E silencer is absolutely dependent on the presence of a functional SIR4 gene product, is lost within 1 min following stress induction, and is fully reestablished within 15 min following a return to nonstressful conditions. Similar kinetics of reestablishment are seen in HMRE/HSP82 and HMRa/HSP82 strains, indicating that complete repression can be mediated over thousands of base pairs within minutes. DNase I chromatin mapping reveals that the ABF1, RAP1, and autonomously replicating sequence factor binding sites within the silencer are constitutively occupied in chromatin, unaltered by heat shock or the presence of SIR4. Similarly, the heat shock factor binding site upstream of HSP82 remains occupied under such conditions, suggesting concurrent occupancy of silencer and activator binding sites. Our results are consistent with a model in which silencing at the HMRE/HSP82 allele is mediated by direct or indirect contacts between the silencer protein complex and heat shock factor.

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