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Updated: Aug 7, 2026

Studying Protein Import into Chloroplasts Using Protoplasts
Published on: December 10, 2018
Evidence for an ER to Golgi to chloroplast protein transport pathway
Resmi N Radhamony1, Steven M Theg
1Section of Plant Biology, University of California-Davis, Davis, CA 95616, USA.
Abstract:
Chloroplast protein import is generally believed to occur posttranslationally through the interaction of a precursor protein with the Toc and Tic transport apparatus in the plastid envelope membranes. The cleavable N-terminal transit peptide present on translocated proteins has been considered to be essential and sufficient for targeting. This idea was recently challenged when an analysis of the chloroplast proteome revealed many proteins without a predicted transit peptide. A recent study demonstrates the existence of a novel chloroplast targeting pathway, starting with protein entry into the endoplasmic reticulum and involving the Golgi apparatus.
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