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Updated: Aug 11, 2026
12:13
Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
Simple fold composition and modular architecture of the nuclear pore complex
Damien Devos1, Svetlana Dokudovskaya, Rosemary Williams
1Department of Biopharmaceutical Sciences, University of California, Mission Bay QB3, 1700 4th Street, Suite 503B, San Francisco, CA 94143-2552, USA.
Summary
Researchers mapped the protein folds of the nuclear pore complex (NPC), revealing a simple, modular structure. This finding explains how the NPC evolved from basic protein components.
Area of Science:
- Structural biology
- Cell biology
- Biochemistry
Background:
- The nuclear pore complex (NPC) regulates transport between the nucleus and cytoplasm.
- Current structural data for nucleoporins (nups) is limited, hindering a full understanding of NPC architecture.
Purpose of the Study:
- To computationally and biochemically determine the protein folds for most residues in yeast and vertebrate nups.
- To elucidate the structural composition and organization of the NPC.
Main Methods:
- Combined computational and biochemical analyses.
- Fold assignment for nucleoporin residues.
Main Results:
- Assigned folds for ~95% of residues in yeast and vertebrate nups.
- Identified only eight distinct fold types, with three dominant folds comprising ~85% of NPC structure.
- Revealed a modular architecture with transmembrane, scaffold, and FG-repeat domains.
Conclusions:
- The NPC exhibits remarkable simplicity in composition and modularity in architecture across eukaryotes.
- Structural similarities suggest a common evolutionary origin for NPCs and coated vesicles.
- The NPC likely evolved through gene duplication from a limited set of ancestral proteins.
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