Architecture of the linker-scaffold in the nuclear pore

Petrovic, S.; Samanta, D.; Perriches, T.; Bley, C. J.; Thierbach, K.; Brown, B.; Nie, S.; Mobbs, G. W.; Stevens, T. A.; Liu, X.; Hoelz, A.

doi:10.1101/2021.10.26.465796

bioRxiv · 10.1101/2021.10.26.465796

Architecture of the linker-scaffold in the nuclear pore

Petrovic, S.·Samanta, D.·Perriches, T.·Bley, C. J.·Thierbach, K.·Brown, B.·Nie, S.·Mobbs, G. W.·Stevens, T. A.·Liu, X.·Hoelz, A.

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Abstract

The nuclear pore complex (NPC) is the sole bidirectional gateway for nucleocytoplasmic transport. Despite recent progress in elucidating the arrangement of the structured scaffold building blocks in the NPC symmetric core, their cohesion by multivalent unstructured linker proteins remained elusive. Combining biochemical reconstitution, high resolution structure determination, docking into cryo-electron tomographic reconstructions, and physiological validation, we elucidated the architecture of the entire linker-scaffold, yielding a near-atomic composite structure of the symmetric core accounting for [~]77 MDa of the human NPC. Whereas linkers generally play a rigidifying role, the linker-scaffold of the NPC provides the plasticity and robustness necessary for the reversible constriction and dilation of its central transport channel. Our results complete the structural characterization of the NPC symmetric core, providing a rich foundation for future functional studies. One sentence summaryAn interdisciplinary analysis established the near-atomic molecular architecture and evolutionary conservation of the linker-scaffold of the human nuclear pore complex.

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Petrovic, S., Samanta, D., Perriches, T., Bley, C. J., Thierbach, K., Brown, B., Nie, S., Mobbs, G. W., Stevens, T. A., Liu, X., Hoelz, A.. 2021-10-26. Architecture of the linker-scaffold in the nuclear pore. https://doi.org/10.1101/2021.10.26.465796

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