Pex13p: docking or cargo handling protein?

Chris Williams; Ben Distel

doi:10.1016/j.bbamcr.2006.09.007

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PubMed · 17056133

Pex13p: docking or cargo handling protein?

Chris Williams·Ben Distel

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Abstract

The Src homology 3 (SH3) domain-containing peroxisomal membrane protein Pex13p is an essential component of the import machinery for matrix proteins and forms a binding site for the peroxisomal targeting type I (PTS1) receptor Pex5p. The interaction between these two proteins can be described as novel in several ways. In the yeasts Saccharomyces cerevisiae and Pichia pastoris, the SH3 domain itself is responsible for the interaction but not via the typical P-x-x-P motifs that are common to SH3 ligands as Pex5p lacks such a motif. Instead, a region of Pex5p containing a W-x-x-x-F/Y motif is crucial for this binding. In mammals, again W-x-x-x-F/Y motifs appear to be important for the interaction but the SH3 domain seems not to be the site for Pex5p binding, this being located in the N-terminus of Pex13p. Despite these differences in the details of the Pex13p-Pex5p interaction, the association of the two proteins is a crucial step in Pex5p-mediated protein import into peroxisomes in both yeasts and mammals.

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Amino Acid Motifs Amino Acid Sequence Animals Binding Sites Mammals Membrane Proteins Membrane Transport Proteins Models, Molecular Molecular Sequence Data Peroxisome-Targeting Signal 1 Receptor Pichia Protein Binding Protein Transport Saccharomyces cerevisiae Proteins Sequence Homology, Amino Acid src Homology Domains Journal Article Research Support, Non-U.S. Gov't Review

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Chris Williams, Ben Distel. 2006-09-14. Pex13p: docking or cargo handling protein?. https://doi.org/10.1016/j.bbamcr.2006.09.007

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