title: Protein import into cyanelles.
abstract: "Cyanelles" are peptidoglycan-armored plastids of glaucocystophyte algae with close morphological and biochemical resemblance to endosymbiotic cyanobacteria. Genome sequencing and phylogenetic analysis have placed cyanelles on the earliest branch of phototrophic eukaryotes after the singular primary endosymbiotic event, the closest relatives to cyanobacteria among extant plastids. This model is supported by similar mechanisms for the targeting of nucleus-encoded cyanelle and chloroplast precursor proteins whose genes were transferred to the nucleus after the endosymbiotic event. As in chloroplasts, a prokaryote-type Sec preprotein translocase is shown to operate in cyanelle thylakoid membranes.
authors.affiliation: Institut für Biochemie und Molekulare Zellbiologie, Universität Wien und Ludwig-Boltzmann-Forschungsstelle für Biochemie, Dr. Bohrgasse 9, A-1030 Vienna, Austria.
authors.forename: Jürgen M
authors.initials: JM
authors.lastname: Steiner
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Löffelhardt
mesh_terms: D020418:Algal Proteins / Q000235:genetics / Q000502:physiology; D000595:Amino Acid Sequence; D001692:Biological Transport; D056890:Eukaryota / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D008954:Models, Biological; D008969:Molecular Sequence Data; D015388:Organelles / Q000502:physiology*; D021381:Protein Transport / Q000502:physiology*; D017386:Sequence Homology, Amino Acid
chemical_list: D020418:Algal Proteins