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Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
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Nuclear export of pre-60S particles through the nuclear pore complex
Zongqiang Li1,2, Shuaijiabin Chen1,2, Liang Zhao1,2
1School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.
Nature
|May 31, 2023
Summary
Researchers visualized yeast nuclear pore complex (NPC) structures, revealing how export factors facilitate the transport of large ribosomal subunits (pre-60S particles) through the NPC channel.
Area of Science:
- Cell Biology
- Structural Biology
- Molecular Biology
Background:
- The nuclear pore complex (NPC) regulates the transport of molecules between the nucleus and cytoplasm.
- Ribosomal subunit precursors (pre-60S and pre-40S particles) are large cargoes requiring export factors for NPC translocation.
Purpose of the Study:
- To determine the structure of native pre-60S particles within yeast NPCs.
- To elucidate the mechanism of pre-60S particle export through the NPC.
Main Methods:
- Cryo-electron microscopy (cryo-EM) was used to visualize native pre-60S particles in yeast NPCs.
- In silico analysis was performed to study the distribution of pre-60S particles within the NPC.
Main Results:
- The cryo-EM structure revealed known assembly factors and multiple export factors bound to pre-60S particles.
- These factors interact with phenylalanine-glycine (FG) repeats in nucleoporins, forming anchor sites for NPC binding and facilitating passage.
- In silico analysis showed NPCs can accommodate up to four pre-60S particles, which are enriched in inner ring regions.
Conclusions:
- Export factors play a crucial role in mediating pre-60S particle passage through the NPC.
- A translocation model for pre-60S particle export is proposed, highlighting the importance of factor interactions with the NPC's FG-repeat network.
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