Related Experiment Video
Updated: Jun 23, 2026
10:36
Measurements of Physiological Stress Responses in C. Elegans
Published on: May 21, 2020
Genetically encoded bioluminescent indicators for stress hormones.
Sung Bae Kim1, Moritoshi Sato, Hiroaki Tao
1National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba 305-8569, Japan.
Analytical Chemistry
|April 25, 2009
Summary
Researchers developed novel bioluminescent indicators to detect stress hormones like cortisol in cells. Modifications significantly improved sensitivity and accuracy for stress hormone detection.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Stress hormones, such as cortisol, play critical roles in mammalian physiology.
- Accurate and sensitive detection of stress hormones is essential for understanding cellular responses to stress.
- Existing methods for stress hormone detection may lack sensitivity or require complex procedures.
Purpose of the Study:
- To develop novel genetically encoded bioluminescent indicators for sensitive detection of stress hormones in mammalian cells.
- To investigate the impact of protein engineering strategies, including circular permutation (CP) and corepressor motifs, on indicator performance.
- To establish a new platform for real-time monitoring of stress hormone levels within living cells.
Main Methods:
- Synthesis of a genetically encoded bioluminescent probe incorporating the glucocorticoid receptor ligand-binding domain (GR LBD) linked to a LXXLL motif.
- Fusion of Gaussia luciferase (GLuc) fragments around the GR LBD-LXXLL motif to create a single-chain probe.
- Engineering of the probe through circular permutation (CP) and/or the addition of a corepressor motif.
- Characterization of indicator performance, including dose-response curves, detection limits, dynamic range, luminescence, and ligand selectivity.
Main Results:
- The engineered bioluminescent indicators demonstrated biphasic dose-response curves to cortisol upon co-fusion of a corepressor motif.
- Circular permutation (CP) significantly enhanced the detection limit for cortisol by up to 100-fold.
- Combined application of CP and corepressor motifs resulted in synergistic improvements, including a lower detection limit, wider dynamic range, enhanced luminescence, and improved ligand selectivity.
- This study is the first to investigate the contribution of corepressor motifs to single-chain bioluminescent probes.
Conclusions:
- Genetically encoded bioluminescent indicators can be effectively engineered for sensitive stress hormone detection.
- Circular permutation and corepressor motifs are key strategies for optimizing the performance of single-chain bioluminescent probes.
- These engineered indicators offer a promising tool for advancing the study of stress physiology and hormone signaling in mammalian cells.
- The findings provide new insights into enhancing the sensorial properties of single-chain probes.
Related Concept Videos
02:11Reporter Genes
Reporter genes are a type of protein-coding gene that are often tagged to a gene of interest. Once inside a target cell, reporter genes usually produce visually identifiable characteristics like fluorescence and luminescence when expressed along with the gene of interest. Thus, reporter genes “report” the presence or absence of genes of interest in an organism, determine the gene expression pattern, or track the physical location of a DNA segment or protein in the cell.
Commonly used reporter...
Commonly used reporter...
01:30Other Stress Responses in Bacteria
Bacteria have global regulatory systems that control several types of stress mechanisms. These include Pho regulon and the heat shock response, which are essential systems for environmental adaptation, such as nutrient limitation and proteotoxic stress. The Pho regulon and the heat shock response exemplify bacterial resilience, enabling rapid adaptation to fluctuating environmental conditions.Pho RegulonBacteria require phosphorus for essential cellular processes, including nucleic acid...