The world is a complex and dynamic place. Earth takes part in an intricate dance with the moon, surrounding planets, our sun, other stars and entire galaxies. All interact with one another determining our position in the universe. On a much smaller scale, humans consist of trillions of cells that work together to let us walk, run, and think. Each such single living cell is driven by the interaction of about a trillion non-living molecules. Life at all scales is complex, dynamic, and difficult to understand. All these examples, however, have in common that they obey the basic laws of physics. Although we can apply those laws to understand a small part of each system, many interacting parts can behave wildly different and unpredictable. By combining theory and experiment, our lab aims at understanding such system dynamics, studying living (Dynamics in Biology) and non-living (Dynamics in Physics) systems.
How do oscillatory systems with multiple pacemakers synchronize their dynamics?
Felix and Jan have studied what happens when multiple pacemakers compete with each other. Using numerical simulations in a generic reaction-diffusion system, they determined when and how pacemakers synchronize depending on their size, oscillation frequency, and type of coupling. Their work has been published in Chaos. Well done Felix and Jan!
Nuclei determine the spatial origin of mitotic waves
We show how mitotic waves initiate at pacemakers, regions which oscillate faster than their surroundings. In cell-free extracts of Xenopus laevis eggs, we find that nuclei define such pacemakers by concentrating cell cycle regulators. While Felix developed computational models to illustrate how multiple nuclei can collectively determine the pacemaker location, the experiments were carried out by Alexandra, Arno and Liliana. Our work provides insight into how nuclei and spatial system dimensions can control local concentrations of regulators, influencing the emergent behavior of mitotic waves. For more information, see the publication in eLife. Congratulations to everyone for this great team effort!
Mutualistic cross-feeding in microbial systems generates bistability via an Allee effect
Congratulations to Stefan for publishing his latest work in Scientific Reports! In microbial ecosystems, species can interact in a mutualistic way as a result of metabolic cross-feeding. Here, we reduce a theoretical nutrient-explicit model of two mutualistic cross-feeders in a chemostat, uncovering an explicit relation to a growth model with an Allee effect.