Peroxisome targeting signal 1: is it really a simple tripeptide?
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.
Brocard
Cécile
C
Max F Perutz Laboratories, University of Vienna, Department of Biochemistry, Dr. Bohrgasse 9, 1030 Vienna, Austria. Cecile.Brocard@univie.ac.at
Hartig
Andreas
A
D020816:Amino Acid Motifs; D000818:Animals; D006801:Humans; D051188:Knowledge Bases; D009842:Oligopeptides / Q000378:metabolism; D000074435:Peroxisome-Targeting Signal 1 Receptor; D020675:Peroxisomes / Q000378:metabolism*; D021382:Protein Sorting Signals; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D013045:Species Specificity
D009842:Oligopeptides; C000614264:PEX5 protein, human; D000074435:Peroxisome-Targeting Signal 1 Receptor; D021382:Protein Sorting Signals; D018160:Receptors, Cytoplasmic and Nuclear