Pex8p: an intraperoxisomal organizer of the peroxisomal import machinery.
Peroxisomes transport folded and oligomeric proteins across their membrane. Two cytosolic import receptors, Pex5p and Pex7p, along with approximately 12 membrane-bound peroxins participate in this process. While interactions among individual peroxins have been described, their organization into functional units has remained elusive. We have purified and defined two core complexes of the peroxisomal import machinery: the docking complex comprising Pex14p and Pex17p, with the loosely associated Pex13p, and the RING finger complex containing Pex2p, Pex10p, and Pex12p. Association of both complexes into a larger import complex requires Pex8p, an intraperoxisomal protein. We conclude that Pex8p organizes the formation of the larger import complex from the trans side of the peroxisomal membrane and thus might enable functional communication between both sides of the membrane.
Agne
Birgit
B
Abteilung für Zellbiochemie, Ruhr-Universität Bochum, D-44780, Bochum, Germany.
Meindl
Nadja M
NM
Niederhoff
Karsten
K
Einwächter
Henrik
H
Rehling
Peter
P
Sickmann
Albert
A
Meyer
Helmut E
HE
Girzalsky
Wolfgang
W
Kunau
Wolf H
WH
D002352:Carrier Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins; D008565:Membrane Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism / Q000502:physiology*; D008954:Models, Biological; D000074401:Peroxins; D000074428:Peroxisomal Biogenesis Factor 2; D000074435:Peroxisome-Targeting Signal 1 Receptor; D020675:Peroxisomes / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism / Q000502:physiology*; D044767:Ubiquitin-Protein Ligases
D002352:Carrier Proteins; D005656:Fungal Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C492057:PEX10 protein, S cerevisiae; C491335:PEX12 protein, S cerevisiae; C491105:PEX13 protein, S cerevisiae; C499195:PEX14 protein, S cerevisiae; C491361:PEX17 protein, S cerevisiae; D000074401:Peroxins; D000074435:Peroxisome-Targeting Signal 1 Receptor; C404515:Pex8 protein, S cerevisiae; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D000074428:Peroxisomal Biogenesis Factor 2; D044767:Ubiquitin-Protein Ligases