Figure 5.

Changing variables that influence noise in cell size regulation can result in variation to the level of noise in protein concentration. (A) Left: some trajectories of cell size and protein concentration for relatively regulated cell cycle timing (steps = 10). Right: trajectories of cell size and protein concentration for a less regulated cell cycle timing (steps = 1). (B) Protein noise as the squared coefficient of variation for different levels of regulation of cell cycle timing measured as the ${CV}^2$ of the added size which theoretically is the multiplicative inverse of the division steps. (C) Left: some trajectories of cell size and protein concentration for relatively regulated growth rate $\left({CV}_{\mathrm{gr}}^2={10}^{-3}\right)$. Right: some trajectories of cell size and protein concentration for relatively less regulated growth rate $\left({CV}_{\mathrm{gr}}^2={10}^{-1}\right)$. (D) Protein noise for different levels of noise in cell growth rate. (E) Left: some trajectories of cell size and protein concentration for relatively regulated cell splitting $\left({CV}_{\text{div}}^2={10}^{-3}\right)$. Right: trajectories of cell size and protein concentration for a less regulated cell splitting $\left({CV}_{\text{div}}^2={10}^{-1}\right)$. (F) Protein noise for different levels of noise in cell splitting position. The protein is produced by burst events that occur at a rate $k_p=4\ln \left(2\right)$ with a burst size distributed following a geometric distribution with mean $\langle b\rangle =5$. Error bars represent the 95% confidence interval of the simulations using bootstrapping methods.