Cytosolic factors mediate protein insertion into the peroxisomal membrane

FEBS Lett. 1997 Sep 1;414(1):95-8. doi: 10.1016/s0014-5793(97)00975-7.


Following in vitro translation of the 22 kDa peroxisomal membrane protein (Pmp22p), gel filtration analysis of the post-ribosomal supernatant revealed that Pmp22p forms two complexes. Complex I is of high molecular weight, results in a crosslinking product of 80 kDa, and by co-immunoprecipitation with anti-TCP1 antibody was identified as TRiC. In complex II Pmp22p was crosslinked to a yet unknown polypeptide of 40 kDa (P40). This complex exhibited much higher efficiency to insert Pmp22p into the peroxisomal membrane compared to complex I. In a model we suggest that newly synthesized Pmp22p is first bound to TRiC before being transferred to P40 which may function as a cytosolic Pmp22p receptor.

MeSH terms

  • Animals
  • Antibodies / immunology
  • Chaperonin Containing TCP-1
  • Chaperonins / immunology
  • Chromatography, Gel
  • Cytosol / chemistry
  • Cytosol / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Intracellular Membranes / metabolism*
  • Intracellular Signaling Peptides and Proteins*
  • Liver / metabolism
  • Male
  • Membrane Proteins / metabolism*
  • Microbodies / metabolism*
  • Microtubule-Associated Proteins*
  • Mitochondria, Liver / metabolism
  • Nuclear Proteins / metabolism
  • Precipitin Tests
  • Protein Biosynthesis
  • Rats
  • Rats, Wistar
  • Reticulocytes / metabolism
  • Ubiquitin-Protein Ligases
  • t-Complex Genome Region


  • Antibodies
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • Microtubule-Associated Proteins
  • Nuclear Proteins
  • PXMP2 protein, human
  • Pxmp2 protein, rat
  • TCP1 protein, human
  • Tcp1 protein, rat
  • PPP1R11 protein, human
  • Ubiquitin-Protein Ligases
  • Chaperonin Containing TCP-1
  • Chaperonins