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Related Experiment Video

Updated: May 13, 2026

Single-Molecule Imaging of Nuclear Transport

Single-Molecule Imaging of Nuclear Transport

Published on: June 9, 2010

Ring cycle for dilating and constricting the nuclear pore.

Sozanne R Solmaz¹, Günter Blobel, Ivo Melcák

¹Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA. ssolmaz@rockefeller.edu

Proceedings of the National Academy of Sciences of the United States of America

|March 13, 2013

Summary

The nuclear pore complex

Area of Science:

Molecular Biology
Structural Biology
Cell Biology

Background:

The nuclear pore complex (NPC) regulates transport between the nucleus and cytoplasm.
Channel nucleoporins (Nups) like Nup54, Nup58, and Nup62 are crucial for NPC function.
Previous studies established interactomes and structures of Nup58 and Nup62 segments.

Purpose of the Study:

To determine the crystal structure of the free Nup54 segment.
To propose a dynamic model for nuclear pore dilation and constriction.
To understand the role of nucleoporins in regulating nuclear transport.

Main Methods:

X-ray crystallography to determine the structure of the Nup54 segment.
Integration of structural data with previous findings on Nup58 and Nup62.

Related Experiment Videos

Last Updated: May 13, 2026

Single-Molecule Imaging of Nuclear Transport

Single-Molecule Imaging of Nuclear Transport

Published on: June 9, 2010

Computational modeling to propose a 'ring cycle' mechanism.

Main Results:

The Nup54 segment forms a tetrameric helical bundle prone to instability.
A 'ring cycle' model is proposed, involving rearrangements of Nup54 and Nup58 tetramers.
The model describes transitions between a constricted (10-20 nm) and dilated (40-50 nm) pore.
Phenylalanine-glycine (FG) repeats regulate the ring cycle, potentially stabilized by cargo-binding.

Conclusions:

The structural plasticity of Nup54 and Nup58 enables dynamic changes in nuclear pore diameter.
The proposed 'ring cycle' mechanism provides a framework for understanding NPC gating.
Regulation by FG repeats links pore state to cellular transport demands.