The BioGRID | PUBLICATION VIEW

	J. Cell Biol. Oct (1996); 135(1):85-95
Pex13p is an SH3 protein of the peroxisome membrane and a docking factor for the predominantly cytoplasmic PTs1 receptor.
Gould SJ, Kalish JE, Morrell JC, Bjorkman J, Urquhart AJ, Crane DI
Department of Biological Chemistry, Johns Hopkins University School of Medicine, Kennedy Krieger Institute, Baltimore, Maryland 21205, USA. Stephen.Gould@qmail.bs.jhu.edu
Abstract: Import of newly synthesized PTS1 proteins into the peroxisome requires the PTS1 receptor (Pex5p), a predominantly cytoplasmic protein that cycles between the cytoplasm and peroxisome. We have identified Pex13p, a novel integral peroxisomal membrane from both yeast and humans that binds the PTS1 receptor via a cytoplasmically oriented SH3 domain. Although only a small amount of Pex5p is bound to peroxisomes at steady state (< 5%), loss of Pex13p further reduces the amount of peroxisome-associated Pex5p by approximately 40-fold. Furthermore, loss of Pex13p eliminates import of peroxisomal matrix proteins that contain either the type-1 or type-2 peroxisomal targeting signal but does not affect targeting and insertion of integral peroxisomal membrane proteins. We conclude that Pex13p functions as a docking factor for the predominantly cytoplasmic PTS1 receptor.
[PUBMED: 8858165]