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Sealable Femtoliter Chamber Arrays for Cell-free Biology

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Published on: March 11, 2015

Colored extrinsic fluctuations and stochastic gene expression.

Vahid Shahrezaei¹, Julien F Ollivier, Peter S Swain

¹Department of Physiology, Centre for Non-linear Dynamics, McGill University, Montreal, Quebec, Canada.

Molecular Systems Biology

|May 9, 2008

Summary

This summary is machine-generated.

Cellular noise, or extrinsic fluctuations, significantly impacts biochemical networks by affecting protein levels and response times. Understanding these colored fluctuations is key to predicting network behavior and function.

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Area of Science:

Biochemistry
Systems Biology
Computational Biology

Background:

Cellular processes exhibit inherent stochasticity (noise), with intrinsic noise well-understood.
Extrinsic fluctuations, arising from interactions with other cellular systems, are nonspecific and long-lived ('colored').

Purpose of the Study:

To extend stochastic simulation algorithms to incorporate extrinsic fluctuations.
To investigate the impact of extrinsic noise on biochemical network dynamics and variation.

Main Methods:

Modified the standard stochastic simulation algorithm to include extrinsic fluctuations.
Analyzed the effects of these fluctuations on mean protein numbers, intrinsic noise, and network response times.

Main Results:

Extrinsic fluctuations influence mean protein levels and intrinsic noise.
These fluctuations can accelerate network response times and explain observed biological variation.
Correlated extrinsic fluctuations can amplify or attenuate network responses, predicting differential effects of coherent and incoherent feedforward loops.

Conclusions:

Extrinsic fluctuations play a critical role in cellular function and network performance.
The timescales and nonspecificity of extrinsic noise are crucial determinants of biochemical network behavior.