PDBsum entry 3w15

Protein transport

PDB id: 3w15

Contents

Protein chains

336 a.a.

72 a.a.

389 a.a.

Ligands

NO3 ×9

Metals

_MG ×6

Waters ×563

References listed in PDB file

Key reference

• Title: Crystal structure of peroxisomal targeting signal-2 bound to its receptor complex pex7p-Pex21p.
• Authors: D.Pan, T.Nakatsu, H.Kato.
• Ref.: Nat Struct Biol, 2013, 20, 987-993. [DOI no: 10.1038/nsmb.2618]
• PubMed id: 23812376

Abstract

Appropriate targeting of matrix proteins to peroxisomes is mainly directed by two types of peroxisomal targeting signals, PTS1 and PTS2. Although the basis of PTS1 recognition has been revealed by structural studies, that of PTS2 recognition remains elusive. Here we present the crystal structure of a heterotrimeric PTS2-recognition complex from Saccharomyces cerevisiae, containing Pex7p, the C-terminal region of Pex21p and the PTS2 of the peroxisomal 3-ketoacyl-CoA thiolase. Pex7p forms a β-propeller structure and provides a platform for cooperative interactions with both the amphipathic PTS2 helix and Pex21p. The C-terminal region of Pex21p directly covers the hydrophobic surfaces of both Pex7p and PTS2, and the resulting hydrophobic core is the primary determinant of stable complex formation. Together with in vivo and in vitro functional assays of Pex7p and Pex21p variants, our findings reveal the molecular mechanism of PTS2 recognition.