Specific Spatial Localization of Actin and DNA in a Water/Water Microdroplet: Self-Emergence of a Cell-Like Structure

Chembiochem. 2018 Jul 4;19(13):1370-1374. doi: 10.1002/cbic.201800066. Epub 2018 Jun 1.


The effect of binary hydrophilic polymers on a pair of representative bio-macromolecules in a living cell has been examined. The results showed that these bio-macromolecules exhibited specific localization in cell-sized droplets that were spontaneously formed through water/water microphase segregation under crowding conditions with coexisting polymers. In these experiments, a simple binary polymer system with poly(ethylene glycol) (PEG) and dextran (DEX) was used. Under the conditions of microphase segregation, DNA was entrapped within cell-sized droplets rich in DEX. Similarly, F-actin, linearly polymerized actin, was entrapped specifically within microdroplets rich in DEX, whereas G-actin, a monomeric actin, was distributed evenly inside and outside these droplets. This study has been extended to a system with both F-actin and DNA, and it was found that DNA molecules were localized separately from aligned F-actin proteins to create microdomains inside microdroplets, reflecting the self-emergence of a cellular morphology similar to a stage of cell division.

Keywords: DNA; liquids; microdroplets; phase separation; synthetic biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / chemistry*
  • Animals
  • Artificial Cells / chemistry*
  • Chickens
  • DNA / chemistry*
  • Dextrans / chemistry
  • Polyethylene Glycols / chemistry
  • Water / chemistry*


  • Actins
  • Dextrans
  • Water
  • Polyethylene Glycols
  • DNA