Improved coarse-grained model for studying sequence dependent phase separation of disordered proteins. Academic Article uri icon


  • We present improvements to the hydropathy scale (HPS) coarse-grained (CG) model for simulating sequence-specific behavior of intrinsically disordered proteins (IDPs), including their liquid-liquid phase separation (LLPS). The previous model based on an atomistic hydropathy scale by Kapcha and Rossky (KR scale) is not able to capture some well-known LLPS trends such as reduced phase separation propensity upon mutations (R-to-K and Y-to-F). Here, we propose to use the Urry hydropathy scale instead, which was derived from the inverse temperature transitions in a model polypeptide with guest residues X. We introduce two free parameters to shift () and scale () the overall interaction strengths for the new model (HPS-Urry) and use the experimental radius of gyration for a diverse group of IDPs to find their optimal values. Interestingly, many possible (, ) combinations can be used for typical IDPs, but the phase behavior of a low-complexity (LC) sequence FUS is only well described by one of these models, which highlights the need for a careful validation strategy based on multiple proteins. The CG HPS-Urry model should enable accurate simulations of protein LLPS and provide a microscopically detailed view of molecular interactions.

published proceedings

  • Protein Sci

altmetric score

  • 11.1

author list (cited authors)

  • Regy, R. M., Thompson, J., Kim, Y. C., & Mittal, J.

citation count

  • 21

complete list of authors

  • Regy, Roshan Mammen||Thompson, Jacob||Kim, Young C||Mittal, Jeetain

publication date

  • July 2021