Presenting Author Max Planck Institute of Biophysics
Nuclear pore complexes (NPCs) fuse the inner and outer nuclear membranes and mediate nucleocytoplasmic exchange. They are made of 30 different nucleoporins and form a cylindrical architecture around an aqueous central channel. This architecture is highly dynamic in space and time. Variations in NPC diameter were reported, but the physiological circumstances and the molecular details remained unknown. We combined cryo-electron tomography (cryo-ET) with integrative structural modeling to capture the respective large-scale conformational changes in cellulo. While NPCs of exponentially growing cells adopt a dilated conformation, they reversibly constrict upon cellular energy depletion or conditions of hypertonic osmotic stress. We propose a model in which nuclear envelope membrane tension regulates the conformation of the NPC.
