Crystal structures of the human G3BP1 NTF2-like domain visualize FxFG Nup repeat specificity

PLoS One. 2013 Dec 4;8(12):e80947. doi: 10.1371/journal.pone.0080947. eCollection 2013.

Abstract

Ras GTPase Activating Protein SH3 Domain Binding Protein (G3BP) is a potential anti-cancer drug target implicated in several cellular functions. We have used protein crystallography to solve crystal structures of the human G3BP1 NTF2-like domain both alone and in complex with an FxFG Nup repeat peptide. Despite high structural similarity, the FxFG binding site is located between two alpha helices in the G3BP1 NTF2-like domain and not at the dimer interface as observed for nuclear transport factor 2. ITC studies showed specificity towards the FxFG motif but not FG and GLFG motifs. The unliganded form of the G3BP1 NTF2-like domain was solved in two crystal forms to resolutions of 1.6 and 3.3 Å in space groups P212121 and P6322 based on two different constructs, residues 1-139 and 11-139, respectively. Crystal packing of the N-terminal residues against a symmetry related molecule in the P212121 crystal form might indicate a novel ligand binding site that, however, remains to be validated. The crystal structures give insight into the nuclear transportation mechanisms of G3BP and provide a basis for future structure based drug design.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Binding Sites
  • Carrier Proteins / chemistry*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • Cell Cycle Proteins / chemistry*
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Crystallography, X-Ray
  • DNA Helicases
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression
  • Humans
  • Ligands
  • Models, Molecular
  • Molecular Sequence Data
  • Nucleocytoplasmic Transport Proteins / chemistry*
  • Nucleocytoplasmic Transport Proteins / genetics
  • Nucleocytoplasmic Transport Proteins / metabolism
  • Poly-ADP-Ribose Binding Proteins
  • Pregnancy Proteins / chemistry*
  • Pregnancy Proteins / genetics
  • Pregnancy Proteins / metabolism
  • Protein Binding
  • Protein Multimerization
  • RNA Helicases
  • RNA Recognition Motif Proteins
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Repetitive Sequences, Amino Acid
  • Saccharomyces cerevisiae / chemistry
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism

Substances

  • CAPRIN1 protein, human
  • Carrier Proteins
  • Cell Cycle Proteins
  • Ligands
  • NTF2 protein, S cerevisiae
  • NUTF2 protein, human
  • Nucleocytoplasmic Transport Proteins
  • Poly-ADP-Ribose Binding Proteins
  • Pregnancy Proteins
  • RNA Recognition Motif Proteins
  • Recombinant Proteins
  • Saccharomyces cerevisiae Proteins
  • DNA Helicases
  • G3BP1 protein, human
  • RNA Helicases

Grants and funding

The study was supported by University of Copenhagen (DANSCATT), the Alfred Benzon Foundation, the Lundbeck Foundation, Brdr. Hartmanns Foundation, Aase and Ejnar Danielsens Foundation and a University of Copenhagen Ph.D. stipend. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.