Dissecting analogue and digital modes of gene regulation

Date

Apr 7, 2026

Time

3:30 PM - 4:30 PM

Speaker

Prof Martin Howard

Affiliation

John Innes Centre

Series

MPI-PKS Kolloquium

Language

en

Main Topic

Physik

Other Topics

Physik

Description

Quantitative gene regulation at the population level can be achieved by two fundamentally different modes of regulation at individual gene copies. A “digital” mode involves binary ON/OFF expression states, with population level variation arising from the proportion of gene copies that are ON or OFF, while an “analogue” mode involves graded expression levels at each gene copy. We will discuss the contexts in which each mode of regulation is used, focusing on the importance of digital states in epigenetic memory systems. We will then examine how nonlinear feedback can stabilise digital memory states, examining particularly the case of histone modification read-write feedback. One system where such histone memory states are critical is for memory of winter in plants, needed to ensure that flowering occurs only after winter has passed. We will highlight recent interlinked theoretical and experimental progress in understanding how this quantitative memory is set up and then stably propagated. We will also discuss the case of DNA methylation memory, where due to the very low noise present in the maintenance mechanism, analogue memory states do appear to be possible.

Last modified: Mar 11, 2026, 7:38:28 AM