Related Experiment Video
Updated: Jun 28, 2025

Monitoring Stub1-Mediated Pexophagy
Published on: May 12, 2023
Modulation of peroxisomal import by the PEX13 SH3 domain and a proximal FxxxF binding motif
Stefan Gaussmann1,2, Rebecca Peschel3, Julia Ott3
1Technical University of Munich, TUM School of Natural Sciences, Bavarian NMR Center and Department of Bioscience, Lichtenbergstr. 4, 85747, Garching, Germany.
Abstract:
Import of proteins into peroxisomes depends on PEX5, PEX13 and PEX14. By combining biochemical methods and structural biology, we show that the C-terminal SH3 domain of PEX13 mediates intramolecular interactions with a proximal FxxxF motif. The SH3 domain also binds WxxxF peptide motifs in the import receptor PEX5, demonstrating evolutionary conservation of such interactions from yeast to human. Strikingly, intramolecular interaction of the PEX13 FxxxF motif regulates binding of PEX5 WxxxF/Y motifs to the PEX13 SH3 domain. Crystal structures reveal how FxxxF and WxxxF/Y motifs are recognized by a non-canonical surface on the SH3 domain. The PEX13 FxxxF motif also mediates binding to PEX14. Surprisingly, the potential PxxP binding surface of the SH3 domain does not recognize PEX14 PxxP motifs, distinct from its yeast ortholog. Our data show that the dynamic network of PEX13 interactions with PEX5 and PEX14, mediated by diaromatic peptide motifs, modulates peroxisomal matrix import.
More Related Videos
08:27Visualization and Quantification of Endogenous Intra-Organelle Protein Interactions at ER-Mitochondria Contact Sites by Proximity Ligation Assays
Published on: October 20, 2023
07:35Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
Related Concept Videos
Protein Import into the Peroxisomes
Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...
Peroxisomes
Regulation of Nuclear Protein Sorting
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Structure of Porins
Protein Modifications in the RER
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...