Pex14p, more than just a docking protein.
After binding newly synthesized peroxisomal matrix proteins in the cytosol, the second task of Pex5p, the peroxisomal cycling receptor, is to carry these proteins to the peroxisomal membrane. Defining the nature of the events that occur at this membrane system and which ultimately result in the translocation of the cargo proteins into the matrix of the organelle and in the recycling of Pex5p back to the cytosol, is one of the major goals of the research in this field. Presently, it is generally accepted that all these steps are promoted by a large protein complex embedded in the peroxisomal membrane. This docking/translocation machinery or importomer, as it is often called, comprises many different peroxins of which one of the best characterized is Pex14p. Here, we review data regarding this membrane peroxin with emphasis on the interactions that it establishes with Pex5p. The available evidence suggests that the key to understand how folded proteins are capable of passing an apparently impermeable membrane may largely reside in this pair of peroxins.
Azevedo
Jorge E
JE
Instituto de Biologia Molecular e Celular (IBMC) and Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Univ. do Porto, Portugal. jazevedo@ibmc.up.pt
Schliebs
Wolfgang
W
D000818:Animals; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000502:physiology*; D026901:Membrane Transport Proteins; D000074401:Peroxins; D000074435:Peroxisome-Targeting Signal 1 Receptor; D020675:Peroxisomes / Q000378:metabolism*; D011485:Protein Binding; D017510:Protein Folding; D025941:Protein Interaction Mapping; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear / Q000502:physiology; D012097:Repressor Proteins / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology
D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C499195:PEX14 protein, S cerevisiae; C455539:PEX14 protein, human; D000074401:Peroxins; D000074435:Peroxisome-Targeting Signal 1 Receptor; C499193:Pex14 protein, mouse; C499194:Pex14 protein, rat; D018160:Receptors, Cytoplasmic and Nuclear; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins