Structure of the cytoplasmic ring of the Xenopus laevis nuclear pore complex by cryo-electron microscopy single particle analysis

Cell Res. 2020 Jun;30(6):520-531. doi: 10.1038/s41422-020-0319-4. Epub 2020 May 6.

Abstract

The nuclear pore complex (NPC) exhibits structural plasticity and has only been characterized at local resolutions of up to 15 Å for the cytoplasmic ring (CR). Here we present a single-particle cryo-electron microscopy (cryo-EM) structure of the CR from Xenopus laevis NPC at average resolutions of 5.5-7.9 Å, with local resolutions reaching 4.5 Å. Improved resolutions allow identification and placement of secondary structural elements in the majority of the CR components. The two Y complexes in each CR subunit interact with each other and associate with those from flanking subunits, forming a circular scaffold. Within each CR subunit, the Nup358-containing region wraps around the stems of both Y complexes, likely stabilizing the scaffold. Nup205 connects the short arms of the two Y complexes and associates with the stem of a neighboring Y complex. The Nup214-containing region uses an extended coiled-coil to link Nup85 of the two Y complexes and protrudes into the axial pore of the NPC. These previously uncharacterized structural features reveal insights into NPC assembly.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cryoelectron Microscopy
  • Cytoplasm / chemistry
  • Nuclear Pore Complex Proteins / chemistry*
  • Oocytes / chemistry*
  • Protein Conformation
  • Single Molecule Imaging
  • Xenopus laevis*

Substances

  • Nuclear Pore Complex Proteins