title: Sorting signals in the cytosolic tail of plant p24 proteins involved in the interaction with the COPII coat.
abstract: The ability of the cytosolic tail of a plant p24 protein to bind COPI and COPII subunits from plant and animal sources in vitro has been examined. We have found that a dihydrophobic motif in the -7,-8 position (relative to the cytosolic carboxy-terminus), which strongly cooperates with a dilysine motif in the -3,-4 position for COPI binding, is required for COPII binding. In addition, we show that COPI and COPII coat proteins from plant cytosol compete for binding to the sorting motifs in these tails. Only in the absence of the dilysine motif in the -3,-4 position or after COPI depletion could we observe COPII binding to the p24 tail. This competition is not observed when using rat liver cytosol.
authors.affiliation: Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Valencia. Avda Vicente Andrés Estellés, s/n, E-46100 Burjassot, Valencia. Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Contreras
authors.forename: Yaodong
authors.initials: Y
authors.lastname: Yang
authors.forename: David G
authors.initials: DG
authors.lastname: Robinson
authors.forename: Fernando
authors.initials: F
authors.lastname: Aniento
mesh_terms: D020816:Amino Acid Motifs / Q000502:physiology; D000818:Animals; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology; D001665:Binding Sites / Q000502:physiology; D022181:COP-Coated Vesicles / Q000378:metabolism*; D020755:Coat Protein Complex I / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D021381:Protein Transport / Q000502:physiology; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D020755:Coat Protein Complex I; D010446:Peptide Fragments; D018160:Receptors, Cytoplasmic and Nuclear