Architecture of the nuclear pore complex coat

By Tobias Stuwe, Ana R. Correia, Daniel H. Lin, Marcin Paduch, Vincent T. Lu, Anthony A. Kossiakoff, and André Hoelz.

Published in Science. 2015 Mar 6;347(6226):1148-52. PMID: 25745173. PMCID: 5180592. Link to publication page.

Core Facility: Synthetic Antigen Binder (SAB) Generation and Crystallography

Figure 4. Architecture of the NPC coat. (A) Thirty-two copies of the yeast CNC, shown in cartoon representation with a representative subunit colored as in Fig. 1, docked into the cryoelectron tomographic reconstruction of the intact human NPC (3), shown as a gray surface. The outer and inner cytoplasmic and nuclear CNC rings are highlighted in orange, cyan, pink, and blue, respectively. (B) Cartoon representations of 16 yeast CNC copies from the cytoplasmic side of the NPC coat. Schematics indicating the positions assigned to Nup84CTD and Nup133, which were not crystallized, are shown. (C) Interface between the inner and outer CNC rings. Two views of the yeast CNC and its mate from the inner ring are shown. (D) Orientation of the Nup120 β propeller relative to neighboring coat Nups and the membrane. Portions of two CNCs from the cytoplasmic outer ring are shown in cartoon representation. Green and cyan shading indicate the positioning of Nup84CTD and Nup133, respectively. The cyan line represents the N-terminal unstructured segment of Nup133 that binds to Nup120 (9).

Abstract

The nuclear pore complex (NPC) constitutes the sole gateway for bidirectional nucleocytoplasmic transport. Despite half a century of structural characterization, the architecture of the NPC remains unknown. Here we present the crystal structure of a reconstituted ~400-kilodalton coat nucleoporin complex (CNC) from Saccharomyces cerevisiae at a 7.4 angstrom resolution. The crystal structure revealed a curved Y-shaped architecture and the molecular details of the coat nucleoporin interactions forming the central “triskelion” of the Y. A structural comparison of the yeast CNC with an electron microscopy reconstruction of its human counterpart suggested the evolutionary conservation of the elucidated architecture. Moreover, 32 copies of the CNC crystal structure docked readily into a cryoelectron tomographic reconstruction of the fully assembled human NPC, thereby accounting for ~16 megadalton of its mass.