Regulation of Heat Shock Genes by Cytokines

Camptothecin stabilizes the topoisomerase I-DNA covalent intermediate that forms during the relaxation of torsionally strained DNA. By mapping the position of the resultant DNA nicks, we analyzed the distribution of the covalent intermediates formed on heat shock genes in cultured Drosophila melanogaster cells. Topoisomerase I was found to interact with the transcriptionally active genes hsp22, hsp23, hsp26, and hsp28 after heat shock but not with the inactive genes before heat shock. The interaction occurred predominantly within the transcribed region, with specific sites occurring on both the transcribed and nontranscribed strands of the DNA. Little interaction was seen with nontranscribed flanking sequences. Camptothecin only partially inhibited transcription of the hsp28 gene during heat shock, causing a reduced level of transcripts which were nonetheless full length. Topoisomerase I also interacted with the DNA throughout the transcriptionally active hsp83 gene, including an intron, in both heat-shocked and non-heat-shocked cells. The results point to a dynamic set of interactions at the active locus.

Download Full-text

Transcriptome and translatome changes in germinated pollen under heat stress uncover roles of transporter genes involved in pollen tube growth

10.1101/2020.05.29.122937 ◽

2020 ◽

Cited By ~ 1

Author(s):

Laetitia Poidevin ◽

Javier Forment ◽

Dilek Unal ◽

Alejandro Ferrando

Keyword(s):

Arabidopsis Thaliana ◽

Heat Stress ◽

High Temperature ◽

Heat Shock ◽

Pollen Tube ◽

Pollen Tube Growth ◽

Tube Growth ◽

Heat Shock Genes ◽

Germinated Pollen

ABSTRACTPlant reproduction is one key biological process very sensitive to heat stress and, as a consequence, enhanced global warming poses serious threats to food security worldwide. In this work we have used a high-resolution ribosome profiling technology to study how heat affects both the transcriptome and the translatome of Arabidopsis thaliana pollen germinated in vitro. Overall, a high correlation between transcriptional and translational responses to high temperature was found, but specific regulations at the translational level were also present. We show that bona fide heat shock genes are induced by high temperature indicating that in vitro germinated pollen is a suitable system to understand the molecular basis of heat responses. Concurrently heat induced significant down-regulation of key membrane transporters required for pollen tube growth, thus uncovering heat-sensitive targets. We also found that a large subset of the heat-repressed transporters is specifically up-regulated, in a coordinated manner, with canonical heat-shock genes in pollen tubes grown in vitro and semi in vivo, based on published transcriptomes from Arabidopsis thaliana. Ribosome footprints were also detected in gene sequences annotated as non-coding, highlighting the potential for novel translatable genes and translational dynamics.

Download Full-text

1800MHz Radiofrequency electromagnetic radiation: Does it affect heat shock genes expression levels in the rat brain?

Medicine Science | International Medical Journal ◽

10.5455/medscience.2020.06.112 ◽

2020 ◽

Vol 9 (4) ◽

pp. 929

Author(s):

Badel Arslan ◽

Nurcan Aras ◽

Gul Yas ◽

Aysegul Cetinkaya

Keyword(s):

Heat Shock ◽

Electromagnetic Radiation ◽

Rat Brain ◽

Heat Shock Genes ◽

Expression Levels ◽

Genes Expression ◽

Radiofrequency Electromagnetic Radiation

Download Full-text

The Skn7 Response Regulator ofSaccharomyces cerevisiaeInteracts with Hsf1 In Vivo and Is Required for the Induction of Heat Shock Genes by Oxidative Stress

Molecular Biology of the Cell ◽

10.1091/mbc.11.7.2335 ◽

2000 ◽

Vol 11 (7) ◽

pp. 2335-2347 ◽

Cited By ~ 108

Author(s):

Desmond C. Raitt ◽

Anthony L. Johnson ◽

Alexander M. Erkine ◽

Kozo Makino ◽

Brian Morgan ◽

...

Keyword(s):

Oxidative Stress ◽

Heat Shock ◽

Response Regulator ◽

Coiled Coil ◽

Normal Growth ◽

Temperature Sensitive ◽

Regulatory Sequences ◽

Heat Shock Genes

The Skn7 response regulator has previously been shown to play a role in the induction of stress-responsive genes in yeast, e.g., in the induction of the thioredoxin gene in response to hydrogen peroxide. The yeast Heat Shock Factor, Hsf1, is central to the induction of another set of stress-inducible genes, namely the heat shock genes. These two regulatory trans-activators, Hsf1 and Skn7, share certain structural homologies, particularly in their DNA-binding domains and the presence of adjacent regions of coiled-coil structure, which are known to mediate protein–protein interactions. Here, we provide evidence that Hsf1 and Skn7 interact in vitro and in vivo and we show that Skn7 can bind to the same regulatory sequences as Hsf1, namely heat shock elements. Furthermore, we demonstrate that a strain deleted for the SKN7 gene and containing a temperature-sensitive mutation in Hsf1 is hypersensitive to oxidative stress. Our data suggest that Skn7 and Hsf1 cooperate to achieve maximal induction of heat shock genes in response specifically to oxidative stress. We further show that, like Hsf1, Skn7 can interact with itself and is localized to the nucleus under normal growth conditions as well as during oxidative stress.

Download Full-text