title: The role of the N-terminal domain of chloroplast targeting peptides in organellar protein import and miss-sorting.
abstract: We have analysed 385 mitochondrial and 567 chloroplastic signal sequences of proteins found in the organellar proteomes of Arabidopsis thaliana. Despite overall similarities, the first 16 residues of transit peptides differ remarkably. To test the hypothesis that the N-terminally truncated transit peptides would redirect chloroplastic precursor proteins to mitochondria, we studied import of the N-terminal deletion mutants of ELIP, PetC and Lhcb2.1. The results show that the deletion mutants were neither imported into chloroplasts nor miss-targeted to mitochondria in vitro and in vivo, showing that the entire transit peptide is necessary for correct targeting as well as miss-sorting.
authors.affiliation: Department of Biochemistry and Biophysics, Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Shashi
authors.initials: S
authors.lastname: Bhushan
authors.forename: Claus
authors.initials: C
authors.lastname: Kuhn
authors.forename: Anna-Karin
authors.initials: AK
authors.lastname: Berglund
authors.forename: Christian
authors.initials: C
authors.lastname: Roth
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Glaser
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology; D010940:Plant Proteins / Q000737:chemistry; D030821:Plants, Genetically Modified; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D020543:Proteome / Q000737:chemistry; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D020539:Sequence Analysis, Protein; D014026:Nicotiana / Q000166:cytology
chemical_list: D010455:Peptides; D010940:Plant Proteins; D020543:Proteome; D011993:Recombinant Fusion Proteins