title: Yeast pex1 cells contain peroxisomal ghosts that import matrix proteins upon reintroduction of Pex1.
abstract: Pex1 and Pex6 are two AAA-ATPases that play a crucial role in peroxisome biogenesis. We have characterized the ultrastructure of the Saccharomyces cerevisiae peroxisome-deficient mutants pex1 and pex6 by various high-resolution electron microscopy techniques. We observed that the cells contained peroxisomal membrane remnants, which in ultrathin cross sections generally appeared as double membrane rings. Electron tomography revealed that these structures consisted of one continuous membrane, representing an empty, flattened vesicle, which folds into a cup shape. Immunocytochemistry revealed that these structures lack peroxisomal matrix proteins but are the sole sites of the major peroxisomal membrane proteins Pex2, Pex10, Pex11, Pex13, and Pex14. Upon reintroduction of Pex1 in Pex1-deficient cells, these peroxisomal membrane remnants (ghosts) rapidly incorporated peroxisomal matrix proteins and developed into peroxisomes. Our data support earlier views that Pex1 and Pex6 play a role in peroxisomal matrix protein import.
authors.affiliation: Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, Netherlands.
authors.forename: Kèvin
authors.initials: K
authors.lastname: Knoops
authors.affiliation: Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, Netherlands.
authors.forename: Rinse
authors.initials: R
authors.lastname: de Boer
authors.affiliation: Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, Netherlands.
authors.forename: Anita
authors.initials: A
authors.lastname: Kram
authors.affiliation: Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, Netherlands i.j.van.der.klei@rug.nl.
authors.forename: Ida J
authors.initials: IJ
authors.lastname: van der Klei
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D004271:DNA, Fungal / Q000378:metabolism; D055032:Electron Microscope Tomography; D007150:Immunohistochemistry; D008027:Light; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism; D008854:Microscopy, Electron; D009154:Mutation; D000074401:Peroxins; D020675:Peroxisomes / Q000378:metabolism*; D021381:Protein Transport / Q000235:genetics; D012097:Repressor Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D004271:DNA, Fungal; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C092128:PEX11 protein, S cerevisiae; C499195:PEX14 protein, S cerevisiae; D000074401:Peroxins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D000251:Adenosine Triphosphatases; D000074183:ATPases Associated with Diverse Cellular Activities; C511586:PEX1 protein, S cerevisiae; C490760:PEX6 protein, S cerevisiae