Nuclear pore complex structure and dynamics revealed by cryoelectron tomography.

Martin Beck; Friedrich Förster; Mary Ecke; Jürgen M Plitzko; Frauke Melchior; Günther Gerisch; Wolfgang Baumeister; Ohad Medalia

doi:10.1126/science.1104808

PubMed · 15514115

Nuclear pore complex structure and dynamics revealed by cryoelectron tomography.

Martin Beck·Friedrich Förster·Mary Ecke·Jürgen M Plitzko·Frauke Melchior·Günther Gerisch·Wolfgang Baumeister·Ohad Medalia

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Abstract

Nuclear pore complexes (NPCs) are gateways for nucleocytoplasmic exchange. To analyze their structure in a close-to-life state, we studied transport-active, intact nuclei from Dictyostelium discoideum by means of cryoelectron tomography. Subvolumes of the tomograms containing individual NPCs were extracted in silico and subjected to three-dimensional classification and averaging, whereby distinct structural states were observed. The central plug/transporter (CP/T) was variable in volume and could occupy different positions along the nucleocytoplasmic axis, which supports the notion that it essentially represents cargo in transit. Changes in the position of the CP/T were accompanied by structural rearrangements in the NPC scaffold.

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Active Transport, Cell Nucleus Animals Cell Nucleus Cryoelectron Microscopy Cytoskeleton Dictyostelium Image Processing, Computer-Assisted Imaging, Three-Dimensional Nuclear Pore Tomography Journal Article

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Martin Beck, Friedrich Förster, Mary Ecke, Jürgen M Plitzko, Frauke Melchior, Günther Gerisch, Wolfgang Baumeister, Ohad Medalia. 2004-10-28. Nuclear pore complex structure and dynamics revealed by cryoelectron tomography.. https://doi.org/10.1126/science.1104808

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