Three-dimensional superresolution fluorescence microscopy maps the variable molecular architecture of the nuclear...

Area of Science:

• Cell Biology
• Structural Biology
• Biophysics

Background:

• Nuclear pore complexes (NPCs) are essential macromolecular machines regulating nucleocytoplasmic transport.
• Vertebrate NPCs comprise ~1000 nucleoporins with a mass >100 MDa, presenting significant structural challenges.
• Previous models lacked comprehensive structural detail for many NPC components due to size and flexibility.

Purpose of the Study:

• To develop an integrated 3D structural map of the NPC in human cells.
• To visualize both central and peripheral NPC subunits with molecular specificity and nanoscale resolution.
• To investigate the conformational variability of NPC structures in situ.

Main Methods:

• Utilized 3D superresolution microscopy.
• Applied computational classification and averaging techniques.
• Analyzed over 10,000 individual NPCs from single human cells.

Main Results:

• Generated the first integrated 3D structural map of the NPC.
• Resolved structures of both central and peripheral NPC subunits.
• Identified distinct conformations of the nuclear ring and nuclear basket.
• Achieved molecular specificity and nanoscale resolution.

Conclusions:

• The developed method provides unprecedented insights into NPC architecture.
• Demonstrated conformational plasticity within NPC components.
• Opened avenues for correlating NPC structural states with cellular functions in situ.