Sequence Determinants of Intracellular Phase Separation by Complex Coacervation of a Disordered Protein

Mol Cell. 2016 Jul 7;63(1):72-85. doi: 10.1016/j.molcel.2016.05.042.


Liquid-liquid phase separation, driven by collective interactions among multivalent and intrinsically disordered proteins, is thought to mediate the formation of membrane-less organelles in cells. Using parallel cellular and in vitro assays, we show that the Nephrin intracellular domain (NICD), a disordered protein, drives intracellular phase separation via complex coacervation, whereby the negatively charged NICD co-assembles with positively charged partners to form protein-rich dense liquid droplets. Mutagenesis reveals that the driving force for phase separation depends on the overall amino acid composition and not the precise sequence of NICD. Instead, phase separation is promoted by one or more regions of high negative charge density and aromatic/hydrophobic residues that are distributed across the protein. Many disordered proteins share similar sequence characteristics with NICD, suggesting that complex coacervation may be a widely used mechanism to promote intracellular phase separation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Nucleus / chemistry
  • Cell Nucleus / metabolism
  • Computer Simulation
  • HeLa Cells
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Intrinsically Disordered Proteins / chemistry*
  • Intrinsically Disordered Proteins / genetics
  • Intrinsically Disordered Proteins / metabolism
  • Membrane Proteins / chemistry*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mice
  • Models, Molecular
  • Mutation
  • Organelles / chemistry*
  • Organelles / metabolism
  • Protein Domains
  • Proteomics / methods
  • Static Electricity
  • Structure-Activity Relationship
  • Surface Properties
  • Time Factors
  • Transfection


  • Intrinsically Disordered Proteins
  • Membrane Proteins
  • nephrin