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Updated: May 18, 2026
08:28
Measurement of Force-Sensitive Protein Dynamics in Living Cells Using a Combination of Fluorescent Techniques
Published on: November 2, 2018
Force fluctuations impact kinetics of biomolecular systems
Elena F Koslover1, Andrew J Spakowitz
1Biophysics Program, Stanford University, Stanford, California 94305, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
Molecular force fluctuations significantly impact biological process rates. Our model shows these fluctuations, not just average force, are crucial for understanding transition kinetics, like RNA polymerase pausing.
Area of Science:
- Biophysics
- Molecular Biology
- Biochemistry
Background:
- Biological processes are often force-dependent.
- Molecular forces fluctuate due to thermal noise and active cellular processes.
- These fluctuations can alter biomolecular rate constants.
Purpose of the Study:
- To investigate the impact of force fluctuations on the kinetics of force-dependent biological processes.
- To model the pausing of eukaryotic RNA polymerase during transcription of nucleosomal DNA, incorporating force fluctuations.
Main Methods:
- Developed a computational model to simulate biomolecular processes under fluctuating forces.
- Applied the model to analyze the pausing kinetics of eukaryotic RNA polymerase transcribing nucleosomal DNA.
- Compared model predictions with and without force fluctuations.
Main Results:
- Force fluctuations dramatically affect transition kinetics, yielding different predictions than average force alone.
- The timescale of force fluctuations significantly influences overall rates and the relevant force regime.
- Transient high-force events are critical for determining kinetics in fluctuating cellular environments.
Conclusions:
- Fluctuating forces, not just average force, are essential for accurately modeling force-dependent biological processes.
- Understanding force fluctuation dynamics is key to predicting cellular behavior in vivo.
- Transient force behaviors play a vital role in cellular kinetics.
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