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Updated: Aug 20, 2026

Studying Protein Import into Chloroplasts Using Protoplasts
Published on: December 10, 2018
Mechanisms of protein import and routing in chloroplasts
1Department of Biology, University of Leicester, Leicester LE1 7RH, UK. rpj3@lec.ac.uk
Abstract:
The vast majority of the approximately 3000 different proteins required to build a fully functional chloroplast are encoded by the nuclear genome and translated on cytosolic ribosomes. As chloroplasts are each surrounded by a double-membrane system, or envelope, sophisticated mechanisms are necessary to mediate the import of these nucleus-encoded proteins into chloroplasts. Once inside the organelle, many chloroplast proteins engage one of four additional protein sorting mechanisms that direct targeting to the internal thylakoid membrane system.
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