Engineering Synthetic Turing Patterns Georg Wachter*,☥, Mark Isalan*,+, Robert Endres*

Introduction What are Turing patterns?

Why are we not just blobs of cells? Emerging patterns Legendary mathematician thought he Armed with just a simple set of rules, cells can become might know the answer: Our cells are governed by part of a structured, multicellular organism. This simple rules that lead to complex patterning. These phenomenon of the whole being more complex than the 'Turing patterns' shape our brains, fngers and explain sum of its parts is called emergence.1 why zebras have stripes.1

Turing Patterns! Simple rules Intricate pattern

Self organising and repairing Turing patterns do not need any external cues to self organise - this comes with the added bonus that they Why engineer Turing patterns? can repair themselves! In the future, this property might Engineering regularly spaced, stable Turing patterns be used to engineer self repairing tissue. could open the door to many medical advances - Self repairing Turing pattern on zebrafsh skin3 including tissue and organoid engineering, as well as advanced biomaterials. Furthermore it can give us a deeper understanding of how we develop into organised, multicellular organisms.2

Considerations Approach

Does growth change the pattern? How to design a Turing pattern? Turing Patterns usually form during Turing patterns are difcult to build in the lab. development, when cells divide. In the lab, we Many variables exist that infuence pattern are screening for Turing patterns in bacterial colonies formation - however not all variables are equally that grow. This radial growth can change the pattern important! Using machine learning and mathematical we expect to see in the microscope.4 modelling, we can predict which variables we will need to look at more closely in the lab.5 Growth rate Slow Intermediate Fast Unguided Design Guided Design

What do patterns in 3D look like? People don't grow as fat disks… Some experiments Changing variable 1 has no might rely on a third dimension as well. This can make 1% of attempted impact - focus on variable 2! the pattern more irregular. experiments give Turing patterns… Variable 1 Variable 2 But why only those, and -1 Take slice how do we get more? Relevance

References Author information 1. A. M. Turing, 1952: The Chemical Basis of * Department of Life Sciences, Imperial College London 2. B. P. Teague, P. Guye and R. Weiss, 2016: Synthetic Morphogenesis + Centre for Synthetic Biology, Imperial College London 3. S. Kondo and T. Miura, 2010: Reaction-Difusion Model as a Framework for Understanding Biological ☥ [email protected] 4. C. Konow et al., 2019: Turing patterns on radially growing domains: experiments and simulations. 5. C. D. Smolke and P. A. Silver, 2011: Informing Biological Design by Integration of Systems and Synthetic Biology