TDP-43 -helical structure tunes liquid-liquid phase separation and function. Academic Article uri icon


  • Liquid-liquid phase separation (LLPS) is involved in the formation of membraneless organelles (MLOs) associated with RNA processing. The RNA-binding protein TDP-43 is present in several MLOs, undergoes LLPS, and has been linked to the pathogenesis of amyotrophic lateral sclerosis (ALS). While some ALS-associated mutations in TDP-43 disrupt self-interaction and function, here we show that designed single mutations can enhance TDP-43 assembly and function via modulating helical structure. Using molecular simulation and NMR spectroscopy, we observe large structural changes upon dimerization of TDP-43. Two conserved glycine residues (G335 and G338) are potent inhibitors of helical extension and helix-helix interaction, which are removed in part by variants at these positions, including the ALS-associated G335D. Substitution to helix-enhancing alanine at either of these positions dramatically enhances phase separation in vitro and decreases fluidity of phase-separated TDP-43 reporter compartments in cells. Furthermore, G335A increases TDP-43 splicing function in a minigene assay. Therefore, the TDP-43 helical region serves as a short but uniquely tunable module where application of biophysical principles can precisely control assembly and function in cellular and synthetic biology applications of LLPS.

published proceedings

  • Proc Natl Acad Sci U S A

altmetric score

  • 61.18

author list (cited authors)

  • Conicella, A. E., Dignon, G. L., Zerze, G. H., Schmidt, H. B., D'Ordine, A. M., Kim, Y. C., ... Fawzi, N. L.

citation count

  • 134

complete list of authors

  • Conicella, Alexander E||Dignon, Gregory L||Zerze, Gül H||Schmidt, Hermann Broder||D'Ordine, Alexandra M||Kim, Young C||Rohatgi, Rajat||Ayala, Yuna M||Mittal, Jeetain||Fawzi, Nicolas L

publication date

  • March 2020