Mapping of interaction sites of the Schizosaccharomyces pombe protein Translin with nucleic acids and proteins: a combined molecular genetics and bioinformatics study

Nucleic Acids Res. 2010 May;38(9):2975-89. doi: 10.1093/nar/gkp1230. Epub 2010 Jan 15.

Abstract

Translin is a single-stranded RNA- and DNA-binding protein, which has been highly conserved in eukaryotes, from man to Schizosaccharomyces pombe. TRAX is a Translin paralog associated with Translin, which has coevolved with it. We generated structural models of the S. pombe Translin (spTranslin), based on the solved 3D structure of the human ortholog. Using several bioinformatics computation tools, we identified in the equatorial part of the protein a putative nucleic acids interaction surface, which includes many polar and positively charged residues, mostly arginines, surrounding a shallow cavity. Experimental verification of the bioinformatics predictions was obtained by assays of nucleic acids binding to amino acid substitution variants made in this region. Bioinformatics combined with yeast two-hybrid assays and proteomic analyses of deletion variants, also identified at the top of the spTranslin structure a region required for interaction with spTRAX, and for spTranslin dimerization. In addition, bioinformatics predicted the presence of a second protein-protein interaction site at the bottom of the spTranslin structure. Similar nucleic acid and protein interaction sites were also predicted for the human Translin. Thus, our results appear to generally apply to the Translin family of proteins, and are expected to contribute to a further elucidation of their functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Binding Sites
  • Carrier Proteins / metabolism
  • Computational Biology
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Interaction Domains and Motifs
  • RNA-Binding Proteins / chemistry*
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism
  • Schizosaccharomyces pombe Proteins / chemistry*
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism
  • Sequence Alignment
  • Two-Hybrid System Techniques

Substances

  • Carrier Proteins
  • DNA-Binding Proteins
  • RNA-Binding Proteins
  • Schizosaccharomyces pombe Proteins
  • TRAX protein, S pombe
  • TSN protein, human
  • tsn1 protein, S pombe