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Updated: Aug 16, 2026

Studying Protein Import into Chloroplasts Using Protoplasts
Published on: December 10, 2018
Chloroplast outer membrane protein targeting and insertion
Nancy R Hofmann1, Steven M Theg
1Section of Plant Biology, University of California - Davis, Davis, CA 95616, USA.
Abstract:
Proteins in the chloroplast outer envelope membrane are nuclear encoded and post-translationally targeted to the chloroplast. The targeting and membrane insertion of these proteins is not well understood. Although early work suggested otherwise, the best-studied outer membrane proteins (OMPs) use both proteins within the chloroplast and NTPs for insertion. There have been conflicting reports in the field regarding protein targeting and insertion, which have probably arisen because of differences in experimental methodology and different interpretations of reduction (versus abolition) of integration. This review summarizes what is known to date about the mechanism of chloroplast OMP targeting.
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