Colored extrinsic fluctuations and stochastic gene expression

  • Shahrezaei V
  • Ollivier J
  • Swain P
  • 205


    Mendeley users who have this article in their library.
  • 144


    Citations of this article.


Stochasticity is both exploited and controlled by cells. Although the intrinsic stochasticity inherent in biochemistry is relatively well understood, cellular variation, or 'noise', is predominantly generated by interactions of the system of interest with other stochastic systems in the cell or its environment. Such extrinsic fluctuations are nonspecific, affecting many system components, and have a substantial lifetime, comparable to the cell cycle (they are 'colored'). Here, we extend the standard stochastic simulation algorithm to include extrinsic fluctuations. We show that these fluctuations affect mean protein numbers and intrinsic noise, can speed up typical network response times, and can explain trends in high-throughput measurements of variation. If extrinsic fluctuations in two components of the network are correlated, they may combine constructively (amplifying each other) or destructively (attenuating each other). Consequently, we predict that incoherent feedforward loops attenuate stochasticity, while coherent feedforwards amplify it. Our results demonstrate that both the timescales of extrinsic fluctuations and their nonspecificity substantially affect the function and performance of biochemical networks.

Author-supplied keywords

  • Biochemical networks
  • Extrinsic noise
  • Intrinsic noise
  • Stochastic simulation algorithm

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • Vahid Shahrezaei

  • Julien F. Ollivier

  • Peter S. Swain

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free