Integrated Structural Analysis of the Human Nuclear Pore Complex Scaffold

• Published in: Cell Vol. 155; no. 6; pp. 1233 - 1243
• Main Authors: Bui, Khanh Huy, von Appen, Alexander, DiGuilio, Amanda L., Ori, Alessandro, Sparks, Lenore, Mackmull, Marie-Therese, Bock, Thomas, Hagen, Wim, Andrés-Pons, Amparo, Glavy, Joseph S., Beck, Martin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.12.2013
• Subjects: crosslinking; electron microscopy; eukaryotic cells; HeLa Cells; Humans; Mass Spectrometry; Models, Molecular; Nuclear Envelope - chemistry; Nuclear Envelope - metabolism; nuclear membrane; Nuclear Pore Complex Proteins - chemistry; Nuclear Pore Complex Proteins - metabolism; Nuclear Pore Complex Proteins - ultrastructure; nucleoporins; Polymerization; tomography
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/j.cell.2013.10.055

The nuclear pore complex (NPC) is a fundamental component of all eukaryotic cells that facilitates nucleocytoplasmic exchange of macromolecules. It is assembled from multiple copies of about 30 nucleoporins. Due to its size and complex composition, determining the structure of the NPC is an enormous challenge, and the overall architecture of the NPC scaffold remains elusive. In this study, we have used an integrated approach based on electron tomography, single-particle electron microscopy, and crosslinking mass spectrometry to determine the structure of a major scaffold motif of the human NPC, the Nup107 subcomplex, in both isolation and integrated into the NPC. We show that 32 copies of the Nup107 subcomplex assemble into two reticulated rings, one each at the cytoplasmic and nuclear face of the NPC. This arrangement may explain how changes of the diameter are realized that would accommodate transport of huge cargoes. [Display omitted] •The human NPC is resolved up to 3.2 nm•32 copies of the hNup107 subcomplex form two reticulated rings•Mitotic phosphorylation sites cluster into intersubcomplex contacts•The hNup214 subcomplex forms a protrusion at the cytoplasmic ring The basic architectural element of the NPC is a dimer of two shifted Nup107 subcomplexes that oligomerizes into two reticulated rings, one each at the cytoplasmic and nuclear face of the NPC. This arrangement, involving 32 copies of Nup107 and duplicating the 8-fold symmetry of the NPC, may explain how changes of the diameter are realized that would accommodate transport of huge cargoes.