To Grow is Not Enough: Impact of Noise on Cell Environmental Response and Fitness

TL;DR

This study demonstrates that increased noise in cell cycle regulation reduces growth rate but enhances cellular adaptability to environmental fluctuations, indicating a trade-off between growth and responsiveness.

Contribution

The paper combines experimental and theoretical approaches to show how noise in cell cycle regulation affects growth and adaptability, revealing a non-optimized balance in cellular fitness.

Findings

Higher noise decreases growth rate.

Increased noise improves environmental response.

Cells optimize for adaptability, not just growth.

Abstract

Quantitative single cell measurements have shown that cell cycle duration (the time between cell divisions) for diverse cell types is a noisy variable. The underlying distribution is mean scalable with a universal shape for many cell types in a variety of environments. Here we show through both experiment and theory that increasing the amount of noise in the regulation of the cell cycle negatively impacts the growth rate but positively correlates with improved cellular response to fluctuating environments. Our findings suggest that even non-cooperative cells in exponential growth phase do not optimize fitness through growth rate alone, but also optimize adaptability to changing conditions. In a manner similar to genetic evolution, increasing the noise in biochemical processes correlates with improved response of the system to environmental changes.