Good things come to those who bait: the peroxisomal docking complex

Rüttermann M; Gatsogiannis C

Abstract

Peroxisomal integrity and function are highly dependent on its membrane and soluble (matrix) components. Matrix enzymes are imported post-translationally in a folded or even oligomeric state, via a still mysterious protein translocation mechanism. They are guided to peroxisomes via the Peroxisomal Targeting Signal (PTS) sequences which are recognized by specific cytosolic receptors, Pex5, Pex7 and Pex9. Subsequently, cargo-loaded receptors bind to the docking complex in an initial step, followed by channel formation, cargo-release, receptor-recycling and -quality control. The docking complexes of different species share Pex14 as their core component but differ in composition and oligomeric state of Pex14. Here we review and highlight the latest insights on the structure and function of the peroxisomal docking complex. We summarize differences between yeast and mammals and then we integrate this knowledge into our current understanding of the import machinery.