Sequence-Specific Polyampholyte Phase Separation in Membraneless Organelles.

Phase Transition of a Disordered Nuage Protein Generates Environmentally Responsive Membraneless Organelles

Cells chemically isolate molecules in compartments to both facilitate and regulate their interactions. In addition to membrane-encapsulated compartments, cells can form proteinaceous and membraneless organelles, including nucleoli, Cajal and PML bodies, and stress granules. The principles that determine when and why these structures form have remained elusive. Here, we demonstrate that the diso...

Physics of Protein Evolutionary Switches and Phase Separation in Membraneless Organelles

It's Raining Liquids: RNA Tunes Viscoelasticity and Dynamics of Membraneless Organelles.

Paradigm-shifting advances have revealed that diverse membraneless organelles originate via liquid-liquid phase separation, but how their distinct structural and functional milieux are specified is not understood. Recent work elucidates that RNA governs the biophysical characteristics of liquid droplets formed by RNA-binding proteins with low-complexity domains and can decelerate pathogenic fib...

Phase Separation and Single-Chain Compactness of Charged Disordered Proteins Are Strongly Correlated.

Liquid-liquid phase separation of intrinsically disordered proteins (IDPs) is a major undergirding factor in the regulated formation of membraneless organelles in the cell. The phase behavior of an IDP is sensitive to its amino acid sequence. Here we apply a recent random-phase-approximation polymer theory to investigate how the tendency for multiple chains of a protein to phase-separate, as ch...

Random-phase-approximation theory for sequence-dependent, biologically functional liquid-liquid phase separation of intrinsically disordered proteins

Intrinsically disordered proteins (IDPs) are typically low in nonpolar/hydrophobic but relatively high in polar, charged, and aromatic amino acid compositions. Some IDPs undergo liquid-liquid phase separation in the aqueous milieu of the living cell. The resulting phase with enhanced IDP concentration can function as a major component of membraneless organelles that, by creating their own IDP-r...