RNA transcription modulates phase transition-driven nuclear body assembly

Significance Living cells contain various membraneless organelles whose size and assembly appear to be governed by equilibrium thermodynamic phase separation. However, the dynamics of this process are poorly understood. Here, we quantify the assembly dynamics of liquid-phase nuclear bodies and find that they can be explained by classical models of phase separation and coarsening. In addition, active nonequilibrium processes, particularly rRNA transcription, can locally modulate thermodynamic parameters to stabilize nucleoli. Our findings demonstrate that the classical phase separation mechanisms long associated with nonliving condensed matter can mediate organelle assembly in living cells, whereas chemical…

• NS
  National Science Foundation

  Awards: CAREER, 1253035
• DR
  Damon Runyon Cancer Research Foundation
• PU
  Princeton University
• SS
  Searle Scholars Program

  Award: 12-SSP-217
• NI
  National Institutes of Health

  Award: 1DP2GM105437-01