12
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Conformational heterogeneity of karyopherin beta2 is segmental.

      Structure(London, England:1993)
      Binding Sites, Crystallography, X-Ray, Humans, Ligands, Models, Molecular, Protein Conformation, beta Karyopherins, chemistry

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Karyopherinbeta2 (Kap beta2) or transportin imports numerous RNA binding proteins into the nucleus. Kap beta2 binds substrates in the cytoplasm and targets them through the nuclear pore complex, where RanGTP dissociates them in the nucleus. Here we report the 3.0 A crystal structure of unliganded Kap beta2, which consists of a superhelix of 20 HEAT repeats. Together with previously reported structures of NLS and Ran complexes, this structure provides understanding of conformational heterogeneity that accompanies ligand binding. The Kap beta2 superhelix is divided into three major segments. Two of them (HEAT repeats 9-13 and 14-18), which constitute the substrate binding site, are rigid elements that rotate relative to each other about a flexible hinge. The third (HEAT repeats 1-8), which constitutes the Ran binding site, exhibits conformational changes throughout its length. An analogous segmental architecture is also observed in Importin beta, suggesting that it is functionally significant and may be conserved in other import karyopherins.

          Related collections

          Author and article information

          Journal
          17997969
          3437625
          10.1016/j.str.2007.09.009

          Chemistry
          Binding Sites,Crystallography, X-Ray,Humans,Ligands,Models, Molecular,Protein Conformation,beta Karyopherins,chemistry

          Comments

          Comment on this article