3MK4

X-Ray structure of human PEX3 in complex with a PEX19 derived peptide

Summary for 3MK4

• Entry DOI: 10.2210/pdb3mk4/pdb
• Descriptor: Peroxisomal biogenesis factor 3, Peroxisomal biogenesis factor 19 (3 entities in total)
• Functional Keywords: membrane, peroxisome, protein transport
• Biological source: Homo sapiens (human); More
• Cellular location: Peroxisome membrane; Multi-pass membrane protein: P56589; Cytoplasm: P40855
• Total number of polymer chains: 2
• Total formula weight: 39824.37

Authors

Schmidt, F.,Treiber, N.,Dodt, G.,Stehle, T. (deposition date: 2010-04-14, release date: 2010-06-30, Last modification date: 2024-04-03)

Primary citation

Schmidt, F.,Treiber, N.,Zocher, G.,Bjelic, S.,Steinmetz, M.O.,Kalbacher, H.,Stehle, T.,Dodt, G.
Insights into peroxisome function from the structure of PEX3 in complex with a soluble fragment of PEX19
J.Biol.Chem., 285:25410-25417, 2010

PubMed Abstract: The human peroxins PEX3 and PEX19 play a central role in peroxisomal membrane biogenesis. The membrane-anchored PEX3 serves as the receptor for cytosolic PEX19, which in turn recognizes newly synthesized peroxisomal membrane proteins. After delivering these proteins to the peroxisomal membrane, PEX19 is recycled to the cytosol. The molecular mechanisms underlying these processes are not well understood. Here, we report the crystal structure of the cytosolic domain of PEX3 in complex with a PEX19-derived peptide. PEX3 adopts a novel fold that is best described as a large helical bundle. A hydrophobic groove at the membrane-distal end of PEX3 engages the PEX19 peptide with nanomolar affinity. Mutagenesis experiments identify phenylalanine 29 in PEX19 as critical for this interaction. Because key PEX3 residues involved in complex formation are highly conserved across species, the observed binding mechanism is of general biological relevance.

PubMed: 20554521
DOI: 10.1074/jbc.M110.138503

Experimental method

X-RAY DIFFRACTION (2.42 Å)