Peroxisome targeting signal 1: is it really a simple tripeptide?

Biochim Biophys Acta. 2006 Dec;1763(12):1565-73. doi: 10.1016/j.bbamcr.2006.08.022. Epub 2006 Aug 24.


Originally, the peroxisomal targeting signal 1 (PTS1) was defined as a tripeptide at the C-terminus of proteins prone to be imported into the peroxisomal matrix. The corresponding receptor PEX5 initiates the translocation of proteins by identifying potential substrates via their C-termini and trapping PTS1s through remodeling of its TPR domain. Thorough studies on the interaction between PEX5 and PTS1 as well as sequence-analytic tools revealed the influence of amino acid residues further upstream of the ultimate tripeptide. Altogether, PTS1s should be defined as dodecamer sequences at the C-terminal ends of proteins. These sequences accommodate physical contacts with both the surface and the binding cavity of PEX5 and ensure accessibility of the extreme C-terminus. Knowledge-based approaches in applied Bioinformatics provide reliable tools to accurately predict the peroxisomal location of proteins not yet determined experimentally.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Motifs
  • Animals
  • Humans
  • Knowledge Bases
  • Oligopeptides / metabolism
  • Peroxisome-Targeting Signal 1 Receptor
  • Peroxisomes / metabolism*
  • Protein Sorting Signals*
  • Protein Structure, Tertiary
  • Protein Transport*
  • Receptors, Cytoplasmic and Nuclear / metabolism*
  • Species Specificity


  • Oligopeptides
  • PEX5 protein, human
  • Peroxisome-Targeting Signal 1 Receptor
  • Protein Sorting Signals
  • Receptors, Cytoplasmic and Nuclear