What dominates fluctuations of cellular growth rate?

Friday, 29 May 2026, 11am to 12pm

Many cells exhibit exponential growth not only at the population level but also at the single-cell level. However, single-cell growth rates fluctuate over time. We distinguish between two conceptually distinct sources of growth rate fluctuations: intrinsic continuous fluctuations resulting from intracellular processes, and fluctuations that originate at division events, which we refer to as kicks. We use a simple model to describe single-cell growth and identify the signatures of continuous noise and division kicks. To infer the true biological behavior reliably from experiments, it is crucial to account for measurement noise. We derive analytical expressions for the statistics of meaningful observables, accounting for continuous fluctuations, division kicks, and measurement noise. Importantly, we find that ignoring measurement noise can lead to incorrect biological conclusions. Our results provide insights into how different sources of growth rate variability and measurement errors influence observed cell size dynamics, offering an interpretable framework for analyzing experimental data in cellular biology.

Speaker(s): Dr Roi Holtzman (Dept of Physics, University of Oxford)

Series: Mathematical Biology and Ecology Seminar Series

Venue: Mathematical Institute - L4 - L4 Mathematical Institute Woodstock Road Oxford Oxfordshire OX2 6GG United Kingdom

Department: Mathematical Institute (Department)

Organiser: Sara Jolliffe

Host: Dr Carles Falco Gandia