Related Experiment Video
Updated: Jul 15, 2026
10:38
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
Published on: September 27, 2012
Cyanobacterial clock, a stable phase oscillator with negligible intercellular coupling.
M Amdaoud1, M Vallade, C Weiss-Schaber
1Laboratoire de Spectrométrie Physique, Centre National de la Recherche Scientifique/Unité Mixte de Recherche 5588, Université Joseph Fourier-Grenoble I, BP 87, 38402 St. Martin d'Hères Cedex, France.
Summary
Cyanobacterial circadian clocks maintain accuracy despite cellular noise. This study demonstrates that clock stability is an intrinsic property, not due to intercellular communication, as coupling effects are negligible.
Area of Science:
- Cellular Biology
- Biophysics
- Systems Biology
Background:
- Cellular functions require accuracy despite molecular noise.
- Cyanobacteria possess a resilient circadian oscillator.
- Resilience may stem from intercellular communication or intrinsic network properties.
Purpose of the Study:
- Investigate the role of intercellular communication in cyanobacterial circadian clock resilience.
- Differentiate the effects of intercellular coupling from intrinsic noise resilience.
- Quantify the intercellular coupling strength in cyanobacteria.
Main Methods:
- Theoretical modeling of interacting noisy phase oscillators.
- Numerical simulations to validate theoretical models.
- Experimental analysis of concurrent cell population phases.
- In situ entrainment experiments to assess external force coupling.
Main Results:
- Theoretical and simulation results distinguished coupling effects from noise.
- Experimental evaluation revealed a negligible intercellular coupling strength.
- Entrainment experiments confirmed detection of external force coupling and mean phase dynamics.
Conclusions:
- Cyanobacterial clock stability is an intrinsic property of the biochemical network.
- Intercellular communication does not significantly contribute to clock resilience.
- The cyanobacterial circadian oscillator exhibits inherent noise resistance.
Related Concept Videos
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:45Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
01:30Bacterial Phylum Cyanobacteria
Cyanobacteria are a diverse group of oxygenic, phototrophic bacteria that played a pivotal role in converting Earth’s atmosphere from anoxic to oxygen-rich billions of years ago. They exhibit remarkable morphological diversity, ranging from unicellular forms to filamentous types, with cell sizes varying between 0.5 μm and 100 μm. Cyanobacteria are classified into five groups: Chroococcales (unicellular, dividing by binary fission), Pleurocapsales (unicellular, dividing by multiple fission),...
01:16Non-equilibrium in the Cell
An important concept in studying metabolism and energy is that of chemical equilibrium. Most chemical reactions are reversible. They can proceed in both directions, releasing energy into their environment in one direction, and absorbing it from the environment in the other direction. The same is true for the chemical reactions involved in cell metabolism, such as the breaking down and building up of proteins into and from individual amino acids, respectively. Reactants within a closed system...
01:45Positive Regulator Molecules
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.