'American Association for the Advancement of Science (AAAS)'
Abstract
The nucleoporins Nup58 and Nup45 are part of the central transport channel of the nuclear pore complex, which is thought to have a flexible diameter. In the crystal structure of an α-helical region of mammalian Nup58/45, we identified distinct tetramers, each consisting of two antiparallel hairpin dimers. The intradimeric interface is hydrophobic, whereas dimer-dimer association occurs through large hydrophilic residues. These residues are laterally displaced in various tetramer conformations, which suggests an intermolecular sliding by 11 angstroms. We propose that circumferential sliding plays a role in adjusting the diameter of the central transport channel