Models of protein production along the cell cycle: an investigation of possible sources of noise

TL;DR

This study uses stochastic models to analyze how various intracellular processes influence protein production noise during the cell cycle, revealing that fluctuations in RNA polymerases and ribosomes contribute less to variability than previously thought.

Contribution

It provides a comprehensive quantitative comparison of multiple intracellular factors affecting protein production noise, highlighting the minimal impact of RNA polymerase and ribosome fluctuations.

Findings

RNA polymerase and ribosome fluctuations have little impact on protein variability

Cell volume growth and division significantly influence protein production noise

The results challenge previous assumptions about sources of cellular noise

Abstract

In this article, we quantitatively study, through stochastic models, the efects of several intracellular phenomena, such as cell volume growth, cell division, gene replication as well as fuctuations of available RNA polymerases and ribosomes. These phenomena are indeed rarely considered in classic models of protein production and no relative quantitative comparison among them has been performed. The parameters for a large and representative class of proteins are determined using experimental measures. The main important and surprising conclusion of our study is to show that despite the signifcant fuctuations of free RNA polymerases and free ribosomes, they bring little variability to protein production contrary to what has been previously proposed in the literature. After verifying the robustness of this quite counter-intuitive result, we discuss its possible origin from a theoretical view, and interpret it as the result of a mean-feld efect.