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Updated: Feb 3, 2026
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Automated Robotic Liquid Handling Assembly of Modular DNA Devices
Published on: December 1, 2017
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DNA Local-Flexibility-Dependent Assembly of Phase-Separated Liquid Droplets
1Institute for Basic Science, Center for Soft and Living Matter, Ulsan, Republic of Korea.
Biophysical Journal
|October 22, 2018
Summary
Cellular membraneless organization relies on liquid-liquid phase separation (LLPS). DNA sequence flexibility, not just charge, dictates LLPS, with nucleotides regulating polypeptide-DNA complex formation and secondary phase separation.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Intracellular components undergo membraneless organization via phase separation.
- Liquid-liquid phase separation (LLPS) is a key mechanism for cellular organization.
Purpose of the Study:
- Investigate the associative LLPS of DNA with cationic polypeptides.
- Determine factors influencing DNA phase separation in polypeptide complexes.
Main Methods:
- Comparative analysis of DNA sequences with varying persistence lengths.
- Studying phase behavior of single-stranded and double-stranded DNA (dsDNA).
- Assessing the effect of free nucleotide triphosphates on LLPS.
Main Results:
- DNA local flexibility, not charge density, is the primary determinant of LLPS.
- Free nucleotide triphosphates promote LLPS of polypeptide-dsDNA complexes, preventing precipitation.
- dsDNA exhibits secondary phase separation into liquid-crystalline subcompartments within droplets.
Conclusions:
- Local DNA flexibility, encoded in its sequence, regulates multicomponent LLPS.
- Nucleotide-dependent regulation and selectivity are crucial for membraneless intracellular organization.
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