Fundamental limits on the suppression of molecular fluctuations.

ABSTRACT: Negative feedback is common in biological processes and can increase a system's stability to internal and external perturbations. But at the molecular level, control loops always involve signalling steps with finite rates for random births and deaths of individual molecules. Here we show, by developing mathematical tools that merge control and information theory with physical chemistry, that seemingly mild constraints on these rates place severe limits on the ability to suppress molecular fluctuations. Specifically, the minimum standard deviation in abundances decreases with the quartic root of the number of signalling events, making it extremely expensive to increase accuracy. Our results are formulated in terms of experimental observables, and existing data show that cells use brute forc

SUBMITTER: Lestas I 

PROVIDER: S-EPMC2996232 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature