Send to

Choose Destination
See comment in PubMed Commons below
Mol Biol Cell. 2004 Jul;15(7):3406-17. Epub 2004 May 7.

Peroxisomal membrane proteins contain common Pex19p-binding sites that are an integral part of their targeting signals.

Author information

  • 1Institut für Physiologische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.


Targeting of peroxisomal membrane proteins (PMPs) is a multistep process that requires not only recognition of PMPs in the cytosol but also their insertion into the peroxisomal membrane. As a consequence, targeting signals of PMPs (mPTS) are rather complex. A candidate protein for the PMP recognition event is Pex19p, which interacts with most PMPs. However, the respective Pex19p-binding sites are ill-defined and it is currently disputed whether these sites are contained within mPTS. By using synthetic peptide scans and yeast two-hybrid analyses, we determined and characterized Pex19p-binding sites in Pex11p and Pex13p, two PMPs from Saccharomyces cerevisiae. The sites turned out to be composed of a short helical motif with a minimal length of 11 amino acids. With the acquired data, it proved possible to predict and experimentally verify Pex19p-binding sites in several other PMPs by applying a pattern search and a prediction matrix. A peroxisomally targeted Pex13p fragment became mislocalized to the endoplasmic reticulum in the absence of its Pex19p-binding site. By adding the heterologous binding site of Pex11p, peroxisomal targeting of the Pex13p fragment was restored. We conclude that Pex19p-binding sites are well-defined entities that represent an essential part of the mPTS.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk