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Updated: Jul 12, 2026

Analysis of Protein Import into Chloroplasts Isolated from Stressed Plants
Published on: November 1, 2016
Mechanism of protein import across the chloroplast envelope
1Department of Biological Sciences, Rutgers University, 101 Warren Street, Newark, NJ 07102, USA.
Abstract:
The development and maintenance of chloroplasts relies on the contribution of protein subunits from both plastid and nuclear genomes. Most chloroplast proteins are encoded by nuclear genes and are post-translationally imported into the organelle across the double membrane of the chloroplast envelope. Protein import into the chloroplast consists of two essential elements: the specific recognition of the targeting signals (transit sequences) of cytoplasmic preproteins by receptors at the outer envelope membrane and the subsequent translocation of preproteins simultaneously across the double membrane of the envelope. These processes are mediated via the co-ordinate action of protein translocon complexes in the outer (Toc apparatus) and inner (Tic apparatus) envelope membranes.
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