Three-Dimensional Architecture of the Isolated Yeast Nuclear Pore Complex: Functional and Evolutionary Implications

• Published in: Molecular cell Vol. 1; no. 2; pp. 223 - 234
• Main Authors: Yang, Qing, Rout, Michael P, Akey, Christopher W
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 1998
• Subjects: Animals; Evolution, Molecular; Freezing; Fungal Proteins - chemistry; Fungal Proteins - ultrastructure; Image Processing, Computer-Assisted; Microscopy, Electron, Scanning Transmission; Molecular Weight; Nuclear Envelope - chemistry; Nuclear Envelope - ultrastructure; Protein Conformation; Saccharomyces - chemistry; Saccharomyces - metabolism; Saccharomyces - ultrastructure; Species Specificity; Vertebrates
• ISSN: 1097-2765; 1097-4164
• DOI: 10.1016/S1097-2765(00)80023-4

We have calculated a three-dimensional map of the yeast nuclear pore complex (yNPC) from frozen-hydrated specimens, thereby providing a direct comparison with the vertebrate NPC. Overall, the smaller yNPC is comprised of an octagonal inner spoke ring that is anchored within the nuclear envelope by a novel membrane-interacting ring. In addition, a cylindrical transporter is located centrally within the spokes and exhibits a variable radial expansion in projection that may reflect gating. The inner spoke ring, a transmembrane spoke domain, and the transporter are conserved between yeast and vertebrates; hence, they are required to form a functional NPC. However, significant alterations in NPC architecture have arisen during evolution that may be correlated with differences in nuclear transport regulation or mitotic behavior.