Send to

Choose Destination
Nat Cell Biol. 2010 Mar;12(3):273-7. doi: 10.1038/ncb2027. Epub 2010 Feb 14.

The peroxisomal importomer constitutes a large and highly dynamic pore.

Author information

Biophysik, FB Biologie/Chemie, Universität Osnabrück, Germany.


The peroxisomal protein import machinery differs fundamentally from known translocons (endoplasmic reticulum, mitochondria, chloroplasts, bacteria) as it allows membrane passage of folded, even oligomerized proteins. However, the mechanistic principles of protein translocation across the peroxisomal membrane remain unknown. There are various models that consider membrane invagination events, vesicle fusion or the existence of large import pores. Current data show that a proteinaceous peroxisomal importomer enables docking of the cytosolic cargo-loaded receptors, cargo translocation and receptor recycling. Remarkably, the cycling import receptor Pex5p changes its topology from a soluble cytosolic form to an integral membrane-bound form. According to the transient pore hypothesis, the membrane-bound receptor is proposed to form the core component of the peroxisomal import pore. Here, we demonstrate that the membrane-associated import receptor Pex5p together with its docking partner Pex14p forms a gated ion-conducting channel which can be opened to a diameter of about 9 nm by the cytosolic receptor-cargo complex. The newly identified pore shows striking dynamics, as expected for an import machinery translocating proteins of variable sizes.

[Indexed for MEDLINE]

Publication type, MeSH terms, Substances

Publication type

MeSH terms


Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center