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Updated: May 18, 2026
10:49
Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
Structural evolution of the membrane-coating module of the nuclear pore complex
Xiaoping Liu1, Jana M Mitchell, Richard W Wozniak
1Laboratory of Cell Biology, Rockefeller University, New York, NY 10065, USA.
Summary
The nucleoporin Nup37 binds to the nuclear pore complex coatomer module, specifically to Sp-Nup120. This interaction, revealed by structural analysis, clarifies the evolution of the nuclear pore complex from yeast to metazoa.
Area of Science:
- Cell Biology
- Structural Biology
- Evolutionary Biology
Background:
- The nuclear pore complex (NPC) coatomer module is essential for nuclear envelope structure.
- Evolution shows an increase in coatomer module size from yeast to metazoa.
- The role of nucleoporin Nup37 in the heptamer-octamer transition was unclear.
Purpose of the Study:
- To determine the binding interaction between Nup37 and the NPC coatomer module.
- To elucidate the atomic-level details of the Nup37-Nup120 interaction.
- To understand the evolutionary implications of Nup37 acquisition.
Main Methods:
- Recombinant nucleoporin expression and purification.
- Crystallographic analysis of Sp-Nup37 and Sp-Nup120 complex.
- Structural determination of protein domains and interactions.
Main Results:
- Sp-Nup37 specifically binds Sp-Nup120, not Sc-Nup120.
- Nup37 folds into a seven-bladed β-propeller.
- Sp-Nup120(1-950) also forms a propeller domain with a conserved insert crucial for Nup37 binding.
Conclusions:
- The Nup37-Nup120 interaction is key to the evolution of the NPC coatomer module.
- Structural insights reveal how Nup37 integrates into the larger coatomer complex.
- This study clarifies the assembly and evolutionary trajectory of the NPC.
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