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Updated: May 22, 2026
10:39
Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
The human nuclear pore complex as revealed by cryo-electron tomography
Tal Maimon1, Nadav Elad, Idit Dahan
1Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University, Beer-Sheva, 84105, Israel.
Structure (London, England : 1993)
|May 29, 2012
Summary
This study reveals the detailed structure of human nuclear pore complexes (NPCs), the gateways in the nuclear envelope. The findings highlight unique features and differences compared to other organisms.
Area of Science:
- Structural Biology
- Cell Biology
- Molecular Machines
Background:
- Nuclear pore complexes (NPCs) regulate transport between the cytoplasm and nucleoplasm.
- NPCs are large molecular machines (over 100 MDa) controlling macromolecule passage.
- Understanding NPC structure is crucial for cell function.
Purpose of the Study:
- To determine the high-resolution structure of the human NPC.
- To identify novel structural features and transport routes.
- To compare the human NPC structure with those of other eukaryotes.
Main Methods:
- Cryo-electron tomography of intact human fibroblast cells.
- In silico subtomogram averaging of individual NPCs.
- High-resolution structural reconstruction of the mammalian NPC.
Main Results:
- Determined the structure of the human NPC at ~6.6 nm resolution.
- Identified canonical NPC features, inner lateral channels, and bridge-like structures.
- Revealed alternative peripheral nuclear passage routes.
Conclusions:
- The human NPC exhibits distinct dimensions and organization compared to lower eukaryotes.
- Human NPC structure is similar to amphibian (frog) counterparts.
- Structural insights suggest novel mechanisms for nucleocytoplasmic transport.
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