Plastid protein import and sorting: different paths to the same compartments.
Chloroplasts contain several thousand different proteins, of which more than 95% are encoded on nuclear genes, synthesized in the cytosol as precursor proteins, and imported into the organelle. The major pathways for import and routing have been described; a general import apparatus in the chloroplast envelope and several ancestral translocases in the thylakoid membranes. In this update we focus on some interesting and emerging areas: the Tat translocase, which operates in parallel with the Sec system but transports folded proteins; different routes to the envelope membranes, which promises an understanding of the ways the Tic apparatus sorts transmembrane domains (TMDs) and may also uncover developmental relationships between envelope and thylakoids; and novel routes for proteins into chloroplasts including delivery from the secretory system.
Cline
Kenneth
K
Horticultural Sciences Department and Plant Molecular and Cellular Biology Graduate Program, 1109 Fifield Hall, University of Florida, Gainesville, FL 32611, United States.
Dabney-Smith
Carole
C
D002451:Cell Compartmentation; D007425:Intracellular Membranes / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D018087:Plastids / Q000378:metabolism*; D021381:Protein Transport; D020524:Thylakoids / Q000378:metabolism
D010940:Plant Proteins