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Updated: Aug 12, 2026
06:01
Standardized Methods for Measuring Induction of the Heat Shock Response in Caenorhabditis elegans
Published on: July 3, 2020
Heat shock protein synthesis during development in Caulobacter crescentus
Journal of Bacteriology
|November 1, 1986
Summary
Caulobacter crescentus cells activate heat shock protein (Hsp) synthesis upon temperature increase. These heat shock proteins are regulated by the cell cycle, even under normal conditions.
Area of Science:
- Microbiology
- Molecular Biology
- Cell Biology
Background:
- Caulobacter crescentus exhibits a complex cell cycle.
- Heat shock response is a conserved cellular defense mechanism.
Purpose of the Study:
- To investigate the heat shock response in Caulobacter crescentus.
- To identify heat shock proteins (Hsps) and their regulation during the cell cycle.
Main Methods:
- Immunological cross-reactivity using antibodies against E. coli heat shock proteins.
- Two-dimensional gel electrophoresis of [35S]methionine-labeled cell extracts during heat shock.
Main Results:
- Identified 20 distinct heat shock proteins (Hsps) in C. crescentus.
- Hsps are coordinately expressed in response to heat across the cell cycle.
- Four Hsps (Hsp70, Hsp62, Hsp24b, Hsp23a) are synthesized and cell cycle regulated under normal conditions.
- Hsp62 and Hsp70 are analogous to E. coli GroEL and DnaK, respectively.
Conclusions:
- Heat shock gene activation in C. crescentus is not developmentally controlled.
- Cell cycle regulation of specific Hsps occurs even without heat stress.
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