title: A conserved alpha helical domain at the N-terminus of Pex14p is required for PTS1 and PTS2 protein import in Hansenula polymorpha.
abstract: We have analyzed the highly conserved N-terminus of Hansenula polymorpha Pex14p for its function in peroxisomal matrix protein import. The region comprising aa 10-54 of HpPex14p is predicted to contain three alpha-helices. Its alpha-helical structure was confirmed by CD analysis of a synthetic peptide, corresponding to residues 8-58. Deletion of aa 1-21 of HpPex14p, but not of aa 1-9, completely abolished PTS1 and PTS2 matrix protein import. An extensive mutational analysis of the first alpha-helix (aa 10-21) demonstrated that its secondary structure, as well as residues Phe20 and Leu21, are essential for PTS1 and PTS2 matrix protein import.
authors.affiliation: Molecular Cell Biology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, 9750 AA, Haren, The Netherlands.
authors.forename: Bart
authors.initials: B
authors.lastname: de Vries
authors.forename: Jan A K W
authors.initials: JA
authors.lastname: Kiel
authors.forename: Ruud
authors.initials: R
authors.lastname: Scheek
authors.forename: Marten
authors.initials: M
authors.lastname: Veenhuis
authors.forename: Ida J
authors.initials: IJ
authors.lastname: van der Klei
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D010843:Pichia / Q000254:growth & development / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D008565:Membrane Proteins; D000074437:Peroxisomal Targeting Signal 2 Receptor; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear