Visualizing nuclear pore complex plasticity with pan-expansion microscopy

Area of Science:

• Cell Biology
• Biophysics

Background:

• Investigating nuclear pore complex (NPC) plasticity in response to cell type and environment is crucial.
• Accessible tools are needed to study NPC size and localization dynamics.

Purpose of the Study:

• To develop and utilize novel methods for visualizing and quantifying NPC plasticity.
• To understand the role of LINC complexes and nuclear envelope tension in regulating NPC diameter.
• To examine NPC structural changes in disease models.

Main Methods:

• Pan-expansion microscopy (pan-ExM) for high-resolution imaging of NPCs.
• Machine learning-based segmentation for NPC identification and analysis.
• Experimental manipulations including hyperosmotic shock and LINC complex depletion.

Main Results:

• NPCs display a wide range of diameters, with dilation biased towards the basal nuclear surface.
• Hyperosmotic shock causes NPC constriction, while LINC complex depletion removes basal dilation bias.
• POM121 relocalizes within NPCs in patient-derived neurons with C9orf72 amyotrophic lateral sclerosis.

Conclusions:

• Pan-expansion microscopy is effective for studying NPC plasticity at single-NPC resolution.
• LINC complexes may modulate local nuclear envelope tension to regulate NPC dilation.
• NPC structural alterations, like POM121 shift, are observable in disease contexts.