The crystal structure of the Ran-Nup153ZnF2 complex: a general Ran docking site at the nuclear pore complex

Structure. 2008 Jul;16(7):1116-25. doi: 10.1016/j.str.2008.03.014.

Abstract

Nucleoporin (Nup) 153 is a highly mobile, multifunctional, and essential nuclear pore protein. It contains four zinc finger motifs that are thought to be crucial for the regulation of transport-receptor/cargo interactions via their binding to the small guanine nucleotide binding protein, Ran. We found this interaction to be independent of the phoshorylation state of the nucleotide. Ran binds with the highest affinity to the second zinc finger motif of Nup153 (Nup153ZnF2). Here we present the crystal structure of this complex, revealing a new type of Ran-Ran interaction partner interface together with the solution structure of Nup153ZnF2. According to our complex structure, Nup153ZnF2 binding to Ran excludes the formation of a Ran-importin-beta complex. This finding suggests a local Nup153-mediated Ran reservoir at the nucleoplasmic distal ring of the nuclear pore, where nucleotide exchange may take place in a ternary Nup153-Ran-RCC1 complex, so that import complexes are efficiently terminated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Cell Nucleus / metabolism
  • Crystallography, X-Ray
  • Guanosine Diphosphate / chemistry
  • Guanosine Triphosphate / chemistry
  • Models, Molecular
  • Molecular Sequence Data
  • Nuclear Magnetic Resonance, Biomolecular
  • Nuclear Pore / metabolism
  • Nuclear Pore Complex Proteins / chemistry*
  • Nuclear Pore Complex Proteins / metabolism
  • Rats
  • Sequence Homology, Amino Acid
  • Zinc Fingers*
  • ran GTP-Binding Protein / chemistry*
  • ran GTP-Binding Protein / metabolism

Substances

  • Nuclear Pore Complex Proteins
  • Nup153 protein, rat
  • Guanosine Diphosphate
  • Guanosine Triphosphate
  • ran GTP-Binding Protein

Associated data

  • PDB/2K0C
  • PDB/3CH5