Pex13p Is an SH3 Protein of the Peroxisome Membrane and a Docking Factor for the Predominantly Cytoplasmic PTS1 Receptor
MetadataShow full item record
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.
Journal of Cell Biology
© 1996 Rockefeller University Press. Reproduced in accordance with the copyright policy of the publisher. Use hypertext link for access to the journal's website.
INFORMATION AND COMPUTING SCIENCES