title: Protein targeting into secondary plastids.
abstract: Most of the coding capacity of primary plastids is reserved for expressing some central components of the photosynthesis machinery and the translation apparatus. Thus, for the bulk of biochemical and cell biological reactions performed within the primary plastids, many nucleus-encoded components have to be transported posttranslationally into the organelle. The same is true for plastids surrounded by more than two membranes, where additional cellular compartments have to be supplied with nucleus-encoded proteins, leading to a corresponding increase in complexity of topogenic signals, transport and sorting machineries. In this review, we summarize recent progress in elucidating protein transport across up to five plastid membranes in plastids evolved in secondary endosymbiosis. Current data indicate that the mechanisms for protein transport across multiple membranes have evolved by altering pre-existing ones to new requirements in secondary plastids.
authors.affiliation: Laboratory for Cell Biology, Philipps-University of Marburg, Karl-von-Frisch Strasse 8, D-35032 Marburg, Germany.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Bolte
authors.forename: Lars
authors.initials: L
authors.lastname: Bullmann
authors.forename: Franziska
authors.initials: F
authors.lastname: Hempel
authors.forename: Andrew
authors.initials: A
authors.lastname: Bozarth
authors.forename: Stefan
authors.initials: S
authors.lastname: Zauner
authors.forename: Uwe-G
authors.initials: UG
authors.lastname: Maier