Departmental Papers (Dental)
Document Type
Journal Article
Date of this Version
12-2008
Publication Source
The Plant Cell
Volume
20
Issue
12
Start Page
3405
Last Page
3417
DOI
10.1105/tpc.108.063172
Abstract
The chloroplast inner envelope membrane (IM) plays essential roles in lipid synthesis, metabolite transport, and cellular signaling in plants. We have targeted a model nucleus-encoded IM protein from Arabidopsis thaliana, pre-Tic40-His, by relocating its expression from the nucleus to the chloroplast genome. Pre-Tic40-His was properly targeted, processed, and inserted. It attained correct topology and was folded and assembled into a TIC complex, where it accounted for up to 15% of the total chloroplast protein. These results confirm the existence of a novel pathway for protein targeting to the IM. Tic40-His overexpression resulted in a massive proliferation of the IM (up to 19 layers in electron micrographs) without significant effects on plant growth or reproduction. Consistent with IM proliferation, the expression levels of other endogenous IM proteins (IEP37, PPT, Tic110) were significantly (10-fold) upregulated but those of outer envelope membrane (Toc159), stromal (hsp93, cpn60), or thylakoid (LHCP, OE23) proteins were not increased, suggesting retrograde signal transduction between chloroplast and nuclear genomes to increase lipid and protein components for accommodation of increased accumulation of Tic40. This study opens the door for understanding the regulation of membrane biogenesis within the organelle and the utilization of transgenic chloroplasts as bioreactors for hyperaccumulation of membrane proteins for biotechnological applications.
Copyright/Permission Statement
© American Society of Plant Biologists.
Recommended Citation
Singh, N. D., Li, M., Lee, S., Schnell, D., & Daniell, H. (2008). Arabidopsis Tic40 Expression in Tobacco Chloroplasts Results in Massive Proliferation of the Inner Envelope Membrane and Upregulation of Associated Proteins. The Plant Cell, 20 (12), 3405-3417. http://dx.doi.org/10.1105/tpc.108.063172
Date Posted: 01 March 2022
This document has been peer reviewed.
Comments
At the time of publication, author Henry Daniell was affiliated with the University of Central Florida. Currently, (s)he is a faculty member at the School of Dental Medicine at the University of Pennsylvania.