Perturbation of chromatin architecture on ecdysterone induction of Drosophila melanogaster small heat shock protein genes.

Alterations in the pattern of DNase I hypersensitivity were observed on ecdysterone-stimulated transcription of Drosophila melanogaster small heat shock protein genes. Perturbations were induced near hsp27 and hsp22, coupled with an extensive domain of chromatin unfolding in the intergenic region between hsp23 and the developmentally regulated gene 1. These regions represent candidates for ecdysterone regulatory interactions.

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Small heat shock protein genes are developmentally regulated during stress and non-stress conditions in Blastocladiella emersonii

Fungal Biology ◽

10.1016/j.funbio.2020.02.009 ◽

2020 ◽

Vol 124 (5) ◽

pp. 482-489

Author(s):

Raphaela Castro Georg ◽

Letícia Harumi Oshiquiri ◽

Jomal Rodrigues Barbosa-Filho ◽

Suely Lopes Gomes

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Small Heat Shock Protein ◽

Stress Conditions ◽

Developmentally Regulated ◽

Heat Shock Protein Genes ◽

Blastocladiella Emersonii

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Nucleosomal instability and induction of new upstream protein-DNA associations accompany activation of four small heat shock protein genes in Drosophila melanogaster

Molecular and Cellular Biology ◽

10.1128/mcb.6.3.779-791.1986 ◽

1986 ◽

Vol 6 (3) ◽

pp. 779-791

Author(s):

I L Cartwright ◽

S C Elgin

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Structural Changes ◽

Consensus Sequence ◽

Small Heat Shock Protein ◽

Specific Protein ◽

Dnase I ◽

Coding Region ◽

Protein Factor ◽

Heat Shock Protein Genes

We investigated in detail the structural changes that occur in nuclear chromatin upon activation of the four small heat shock protein genes in D. melanogaster. Both the chemical cleavage reagent methidiumpropyl-EDTA X iron(II) [MPE X Fe(II)] and the nuclease DNase I revealed a complex pattern of four or five hypersensitive sites upstream of each gene before activation. In addition, MPE X Fe(II) detected a short positioned array of nucleosomes located on each coding region. Upon heat shock activation a number of changes in the patterns occurred. For each gene, at least one of the upstream hypersensitive regions was eliminated or substantially shifted in position. Regions were established which became highly refractile to digestion by either MPE X Fe(II) or DNase I and, as such, appeared as small "footprints" in the pattern. The location of these refractile regions relative to the cap site varied for each gene examined. The coding regions themselves became highly accessible to DNase I. The nucleosomal arrays detected by MPE X Fe(II) were characterized by a considerable loss of detail and significantly enhanced accessibility, the extent of which probably reflected the relative transcription rate of each gene. Careful mapping of the location and extent of each upstream footprint and comparison with the DNA sequence revealed the presence at each location of two (or more) contiguous or overlapping segments that bear high homology to the heat shock consensus sequence C-T-N-G-A-A-N-N-T-T-C-N-A-G. A specific protein factor (or factors) is most likely bound at or near these sequence in heat-shocked Drosophila cells.

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Nucleosomal instability and induction of new upstream protein-DNA associations accompany activation of four small heat shock protein genes in Drosophila melanogaster.

Molecular and Cellular Biology ◽

10.1128/mcb.6.3.779 ◽

1986 ◽

Vol 6 (3) ◽

pp. 779-791 ◽

Cited By ~ 53

Author(s):

I L Cartwright ◽

S C Elgin

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Structural Changes ◽

Consensus Sequence ◽

Small Heat Shock Protein ◽

Specific Protein ◽

Dnase I ◽

Coding Region ◽

Protein Factor ◽

Heat Shock Protein Genes

We investigated in detail the structural changes that occur in nuclear chromatin upon activation of the four small heat shock protein genes in D. melanogaster. Both the chemical cleavage reagent methidiumpropyl-EDTA X iron(II) [MPE X Fe(II)] and the nuclease DNase I revealed a complex pattern of four or five hypersensitive sites upstream of each gene before activation. In addition, MPE X Fe(II) detected a short positioned array of nucleosomes located on each coding region. Upon heat shock activation a number of changes in the patterns occurred. For each gene, at least one of the upstream hypersensitive regions was eliminated or substantially shifted in position. Regions were established which became highly refractile to digestion by either MPE X Fe(II) or DNase I and, as such, appeared as small "footprints" in the pattern. The location of these refractile regions relative to the cap site varied for each gene examined. The coding regions themselves became highly accessible to DNase I. The nucleosomal arrays detected by MPE X Fe(II) were characterized by a considerable loss of detail and significantly enhanced accessibility, the extent of which probably reflected the relative transcription rate of each gene. Careful mapping of the location and extent of each upstream footprint and comparison with the DNA sequence revealed the presence at each location of two (or more) contiguous or overlapping segments that bear high homology to the heat shock consensus sequence C-T-N-G-A-A-N-N-T-T-C-N-A-G. A specific protein factor (or factors) is most likely bound at or near these sequence in heat-shocked Drosophila cells.

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