Identification of a novel, intraperoxisomal pex14-binding site in pex13: association of pex13 with the docking

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Peroxisome Staining in Mammalian Cells Using Peroxisome-Specific Probes
05:57

Peroxisome Staining in Mammalian Cells Using Peroxisome-Specific Probes

Published on: December 19, 2025

Annette Schell-Steven1, Katharina Stein, Mara Amoros

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

Molecular and Cellular Biology
|March 31, 2005
PubMed

Insights

The peroxisomal docking complex

Area of Science:

  • Cell Biology
  • Molecular Biology

Background:

  • The peroxisomal docking complex is crucial for importing matrix proteins.
  • Pex14 is the core protein, serving as the docking site for Pex5 and Pex7 import receptors.
  • Pex13 is another essential component associated with this complex.

Purpose of the Study:

  • To investigate the interaction between Pex13 and Pex14.
  • To elucidate the role of Pex5 in the Pex13-Pex14 association.
  • To understand the functional significance of these interactions in peroxisomal protein import.

Main Methods:

  • Investigated direct binding sites between Pex13 and Pex14 using biochemical assays.
  • Utilized mutant strains to assess the impact of altered interactions on peroxisome function.
  • Analyzed peroxisomal protein import pathways (PTS1 and PTS2) and growth phenotypes.

Main Results:

  • Pex13 binds Pex14 directly via its SH3 domain and a novel intraperoxisomal site.
  • Pex5 also contributes to Pex13's association with Pex14.
  • Combined mutations severely impaired PTS1 import and oleic acid growth, while blocking SH3 interaction abolished PTS2 import.

Conclusions:

  • The Pex13-Pex14 association is essential for peroxisomal protein import, involving multiple interaction modes.
  • Pex5 plays a role in this association, suggesting a novel receptor-independent function.
  • Understanding these interactions provides insights into peroxisome biogenesis and function.

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