Cells, the building blocks of life, are masters of information processing, and they're not doing it alone. Theoretical physics is shedding light on the mysterious ways cells self-organize and make decisions in a chaotic world.
Cells as Information Processors:
Imagine a bustling city with no traffic lights or a conductor-less orchestra. That's what self-organizing systems are like, and our cells are no exception. From the assembly of intricate structures to the precise movement of proteins, cells exhibit remarkable coordination. But how do they achieve this in the noisy, chaotic environment of the human body?
The Physics of Self-Organization:
Scientists at the Erzberger Group are delving into this question by applying theoretical physics. They're uncovering how cells use physical forces and their surroundings to self-organize. Anna Erzberger, the group leader, emphasizes the universality of these principles across scales and systems, allowing for concrete predictions.
Binary Decisions in a Crowded World:
PhD student Jenna Elliott, with a physics background, is fascinated by how cells process information. In a crowded cellular environment, cells might use filters, much like a photographer, to make binary decisions. This is crucial for actions like choosing a direction or deciding when to divide.
Elliott's research focuses on spatial signals, like a cell's proximity to an object. She found that certain membrane particles can act as a threshold, converting complex signals into simple 'yes-no' answers. But does this hold true in living cells?
Living Cells and Spatial Patterns:
By collaborating with biologists, the team studied a unicellular organism, S. arctica, and its nuclear pore complexes (NPCs). These NPCs align with microtubules, potentially acting as information highways. The researchers confirmed that spatial patterns in cells can indeed provide filtered information about their surroundings.
Elliott highlights the advantages of understanding these physical rules, enabling the design of synthetic materials that can adapt and compute, offering potential medical applications.
Shape, Signalling, and Feedback Loops:
Tim Dullweber, a former PhD student in the group, took a different path, starting with wet-lab research. He was captivated by the physics at cell boundaries and wanted to understand the interplay between mechanics and signalling. The Notch signalling pathway, unique in its membrane-embedded molecules, caught his attention.
Dullweber and colleagues compared cells to adaptive droplets, finding that they can oscillate and switch shapes rapidly. This is due to feedback loops, where signalling can alter cell mechanics, leading to sharp transitions between cellular states. In the zebrafish embryo, these shape transitions help establish tissue boundaries during development.
Biology Inspires Physics:
These studies not only show how physics helps us understand biology but also how biological systems can inspire new physics. The Theory@EMBL research program aims to explore these complex biological systems further, offering a deeper understanding of the principles governing life.
Controversy and Comment:
But here's where it gets controversial. Are these physical principles truly universal? Can we replicate the complexity of biological systems in synthetic materials? Share your thoughts below, and let's explore the fascinating intersection of physics and biology together.
