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Updated: Jul 3, 2026
13:57
Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
Published on: February 18, 2014
Cooperativity, sensitivity, and noise in biochemical signaling
William Bialek1, Sima Setayeshgar
1Joseph Henry Laboratories of Physics, Lewis-Sigler Institute for Integrative Genomics, and Princeton Center for Theoretical Physics, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|July 23, 2008
Summary
Cooperativity enhances biological signaling sensitivity but does not overcome physical detection limits. The random arrival of signaling molecules remains a noise source unaffected by cooperative binding effects.
Area of Science:
- Biophysics
- Systems Biology
- Biochemistry
Background:
- Cooperative binding of signaling molecules is a known mechanism to enhance biological signaling sensitivity.
- Increased sensitivity is often assumed to enable the detection of smaller signals.
Purpose of the Study:
- To investigate the physical limits of chemoreception in biological signaling systems.
- To determine if cooperativity in signaling molecule binding can reduce the noise inherent in detection.
Main Methods:
- Extending the theoretical framework established by Berg and Purcell on the physical limits of chemoreception.
- Analyzing the impact of diffusing signaling molecules and receptor site interactions on signal detection.
Main Results:
- The random arrival of diffusing signaling molecules at receptor sites acts as a fundamental noise source.
- Cooperativity in binding does not reduce this inherent noise, although it can facilitate reaching detection limits.
Conclusions:
- Cooperativity enhances the ability to reach the physical limits of signal detection but does not lower these limits.
- The inherent noise from molecule diffusion remains a critical factor in biological sensing, irrespective of cooperativity.
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