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Liquid-liquid phase separation within fibrillar networks
Jason X Liu1,2, Mikko P Haataja1,2, Andrej Košmrlj1,2
1Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, 08544, USA.
Nature Communications
|September 28, 2023
Summary
Biomolecular condensates separate into liquid phases within cellular fibrillar networks. Their growth and mechanical interactions depend on network structure, revealing principles of intracellular phase separation.
Area of Science:
- Biophysics
- Cell Biology
- Soft Matter Physics
Background:
- Complex fibrillar networks are crucial for cellular functions, including the formation of biomolecular condensates via liquid-liquid phase separation.
- Mechanical interactions between condensates and these networks are vital for cellular physiology, but the underlying physical principles are not well understood.
Purpose of the Study:
- To investigate the dynamics and mechanics of liquid-liquid phase separation within fibrillar networks.
- To understand how mechanical forces govern condensate behavior and network restructuring.
Main Methods:
- Utilized oil droplets as a model system to condense within biopolymer gels, simulating intracellular environments.
- Analyzed condensate growth dynamics and network deformation under varying conditions.
Main Results:
- Condensates confined within the network pore space exhibit growth in abrupt temporal bursts.
- Condensate restructuring and network deformation are driven by fibril fracture, a process dictated by the balance between condensate capillarity and network strength.
Conclusions:
- This study provides a synthetic analog for intracellular phase separation, enhancing our understanding of the mechanical interplay between biomolecular condensates and cellular fibrillar networks.
- The findings highlight the critical role of mechanical forces and network integrity in regulating condensate behavior within the cell.
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