Deciphering the "Fuzzy" Interaction of FG Nucleoporins and Transport Factors Using Small-Angle Neutron Scattering

Structure. 2018 Mar 6;26(3):477-484.e4. doi: 10.1016/j.str.2018.01.010. Epub 2018 Feb 8.

Abstract

The largely intrinsically disordered phenylalanine-glycine-rich nucleoporins (FG Nups) underline a selectivity mechanism that enables the rapid translocation of transport factors (TFs) through the nuclear pore complexes (NPCs). Conflicting models of NPC transport have assumed that FG Nups undergo different conformational transitions upon interacting with TFs. To selectively characterize conformational changes in FG Nups induced by TFs we performed small-angle neutron scattering (SANS) with contrast matching. Conformational-ensembles derived from SANS data indicated an increase in the overall size of FG Nups is associated with TF interaction. Moreover, the organization of the FG motif in the interacting state is consistent with prior experimental analyses defining that FG motifs undergo conformational restriction upon interacting with TFs. These results provide structural insights into a highly dynamic interaction and illustrate how functional disorder imparts rapid and selective FG Nup-TF interactions.

Keywords: FG nucleoporins; Kap95; NTF2; contrast matching; ensemble analysis; intrinsically disordered proteins; nuclear pore complex; nuclear transport; small-angle neutron scattering; transport factors.

Publication types

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

MeSH terms

  • Models, Molecular
  • Neutron Diffraction
  • Nuclear Pore Complex Proteins / chemistry
  • Nuclear Pore Complex Proteins / metabolism*
  • Nucleocytoplasmic Transport Proteins / chemistry
  • Nucleocytoplasmic Transport Proteins / metabolism*
  • Protein Binding
  • Protein Conformation
  • Scattering, Small Angle

Substances

  • Nuclear Pore Complex Proteins
  • Nucleocytoplasmic Transport Proteins