Nuclear import factors importin α and importin β undergo mutually induced conformational changes upon association

Gino Cingolani, Hilal A. Lashuel, Larry Gerace, Christoph W. Müller

Research output: Contribution to journalArticle

44 Citations (Scopus)


A heterodimer of importin α and importin β accomplishes the nuclear import of proteins carrying classical nuclear localization signals (NLS). The interaction between the two import factors is mediated by the IBB domain of importin α and involves an extended recognition surface as shown by X-ray crystallography. Using a combination of biochemical and biophysical techniques we have investigated the formation of the importin β:IBB domain complex in solution. Our data suggest that upon binding to the IBB domain, importin β adopts a compact, proteolytically resistant conformation, while simultaneously the IBB domain folds into an α helix. We suggest a model to describe how these dual mutually induced conformational changes may orchestrate the nuclear import of NLS cargo in vivo. Copyright (C) 2000 Federation of European Biochemical Societies.

Original languageEnglish
Pages (from-to)291-298
Number of pages8
JournalFEBS Letters
Issue number3
Publication statusPublished - 10 Nov 2000



  • Conformational change
  • IBB domain
  • Importin β
  • Nuclear import

ASJC Scopus subject areas

  • Biophysics
  • Structural Biology
  • Biochemistry
  • Molecular Biology
  • Genetics
  • Cell Biology

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