Near-atomic Structure of the Cytoplasmic Ring of the Xenopus laevis Nuclear Pore Complex

Shi, Y.; Zhou, Q.; Zhu, X.; Huang, G.; Zeng, C.; Zhan, X.; Liang, K.; Wang, Q.; Zhao, Y.; Lei, J.; Liu, M.; Wang, P.; Tao, Q.; Yan, C.

doi:10.1101/2022.02.14.480321

bioRxiv · 10.1101/2022.02.14.480321

Near-atomic Structure of the Cytoplasmic Ring of the Xenopus laevis Nuclear Pore Complex

Shi, Y.·Zhou, Q.·Zhu, X.·Huang, G.·Zeng, C.·Zhan, X.·Liang, K.·Wang, Q.·Zhao, Y.·Lei, J.·Liu, M.·Wang, P.·Tao, Q.·Yan, C.

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Abstract

The nuclear pore complex (NPC) mediates nucleocytoplasmic shuttling. Here we present single-particle cryo-EM structure of the cytoplasmic ring (CR) from the Xenopus laevis NPC at 4.1-4.7 [A] resolutions. The structure of an N-terminal domain of Nup358 was resolved at 3.0 [A], facilitating identification of five Nup358 molecules in each CR subunit. Aside from unveiling the assembly details of the two Y-shaped multicomponent complexes (Y complexes) in each CR subunit, the improved resolutions reveal the C-terminal fragment of Nup160 to be an organizing center at the vertex of each Y complex. Our structures show that the scaffold of a CR subunit comprises five Nup358, two Nup205 and two Nup93 molecules in addition to the previously characterized Y complexes. One-Sentence SummaryImproved resolutions of the cytoplasmic ring (CR) of the Xenopus laevis nuclear pore complex reveal that five Nup358 molecules, together with two copies of interweaved Nup205, Nup93 and Y complexes, constitute the scaffold of each CR subunit.

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Shi, Y., Zhou, Q., Zhu, X., Huang, G., Zeng, C., Zhan, X., Liang, K., Wang, Q., Zhao, Y., Lei, J., Liu, M., Wang, P., Tao, Q., Yan, C.. 2022-02-14. Near-atomic Structure of the Cytoplasmic Ring of the Xenopus laevis Nuclear Pore Complex. https://doi.org/10.1101/2022.02.14.480321

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