Structure of Nup58/45 suggests flexible nuclear pore diameter by intermolecular sliding

Laboratory of Cell Biology, Howard Hughes Medical Institute, Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Science (Impact Factor: 31.48). 04/2007; 315(5819):1729-32. DOI: 10.1126/science.1135730
Source: PubMed

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 alpha-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.

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