Identification of Pex13p a peroxisomal membrane receptor for the PTS1 recognition factor.
We have identified an S. cerevisiae integral peroxisomal membrane protein of M of 42,705 (Pex13p) that is a component of the peroxisomal protein import apparatus. Pex13p's most striking feature is an src homology 3 (SH3) domain that interacts directly with yeast Pex5p (former Pas10p), the recognition factor for the COOH-terminal tripeptide signal sequence (PTS1), but not with Pex7p (former Pas7p), the recognition factor for the NH2-terminal nonapeptide signal (PTS2) of peroxisomal matrix proteins. Hence, Pex13p serves as peroxisomal membrane receptor for at least one of the two peroxisomal signal recognition factors. Cells deficient in Pex13p are unable to import peroxisomal matrix proteins containing PTS1 and, surprisingly, also those containing PTS2. Pex13p deficient cells retain membranes containing the peroxisomal membrane protein Pex11p (former Pmp27p), consistent with the existence of independent pathways for the integration of peroxisomal membrane proteins and for the translocation of peroxisomal matrix proteins.
Erdmann
R
R
Laboratory of Cell Biology, Howard Hughes Medical Institute, Rockefeller University, New York, New York 10021, USA. Erdmann@rzruhr-uni-bochum.de
Blobel
G
G
D000101:Acetyl-CoA C-Acetyltransferase / Q000032:analysis; D000595:Amino Acid Sequence; D001692:Biological Transport; D002374:Catalase / Q000032:analysis; D003001:Cloning, Molecular; D005649:Fumarate Hydratase / Q000032:analysis; D005656:Fungal Proteins / Q000032:analysis; D005800:Genes, Fungal / Q000235:genetics; D007425:Intracellular Membranes / Q000737:chemistry; D008565:Membrane Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism* / Q000502:physiology; D008830:Microbodies / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D019301:Oleic Acid; D000074401:Peroxins; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D017421:Sequence Analysis; D018909:src Homology Domains
D005656:Fungal Proteins; D008565:Membrane Proteins; C092128:PEX11 protein, S cerevisiae; C490455:PEX11A protein, human; C490453:PEX11B protein, human; C491105:PEX13 protein, S cerevisiae; D000074401:Peroxins; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D019301:Oleic Acid; D002374:Catalase; D000101:Acetyl-CoA C-Acetyltransferase; D005649:Fumarate Hydratase