title: Presence of small GTP-binding proteins in the peroxisomal membrane.
abstract: Highly purified peroxisomal membranes stripped from their peripheral membrane proteins and only minimally contaminated with other membranes, contained three GTP-binding proteins of 29, 27 and 25 kDa, respectively. Bound radioactive GTP was displaced by unlabelled GTP, GTP analogs and GDP but not by GMP or other nucleotides. GTP binding was markedly decreased by trypsin treatment of intact purified peroxisomes; it increased 2-3-fold after pretreatment of the animals with a peroxisome proliferator. We conclude that the peroxisomal membrane contains small GTP-binding proteins that are exposed to the cytosol and that are firmly anchored in the membrane. We speculate that these proteins are involved in peroxisome multiplication by fission or budding during peroxisome biogenesis and proliferation.
authors.affiliation: Katholieke Universiteit Leuven, Afdeling Farmacologie, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Verheyden
authors.forename: M
authors.initials: M
authors.lastname: Fransen
authors.forename: P P
authors.initials: PP
authors.lastname: Van Veldhoven
authors.forename: G P
authors.initials: GP
authors.lastname: Mannaerts
mesh_terms: D000818:Animals; D002458:Cell Fractionation; D019204:GTP-Binding Proteins / Q000032:analysis*; D006153:Guanosine Diphosphate / Q000737:chemistry; D006160:Guanosine Triphosphate / Q000737:chemistry; D007425:Intracellular Membranes / Q000737:chemistry*; D008297:Male; D008830:Microbodies / Q000737:chemistry* / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate; D019204:GTP-Binding Proteins