このエントリーをはてなブックマークに追加
ID 53419
FullText URL
Author
Kuromori, Takashi
Takeuchi, Yu
Shimazawa, Atsushi
Sugimoto, Eriko
Shinozaki, Kazuo
Abstract
Ascorbate is an antioxidant and coenzyme for various metabolic reactions in vivo. In plant chloroplasts, high ascorbate levels are required to overcome photoinhibition caused by strong light. However, ascorbate is synthesized in the mitochondria and the molecular mechanisms underlying ascorbate transport into chloroplasts are unknown. Here we show that AtPHT4;4, a member of the phosphate transporter 4 family of Arabidopsis thaliana, functions as an ascorbate transporter. In vitro analysis shows that proteoliposomes containing the purified AtPHT4;4 protein exhibit membrane potential- and Cl-dependent ascorbate uptake. The AtPHT4;4 protein is abundantly expressed in the chloroplast envelope membrane. Knockout of AtPHT4;4 results in decreased levels of the reduced form of ascorbate in the leaves and the heat dissipation process of excessive energy during photosynthesis is compromised. Taken together, these observations indicate that the AtPHT4;4 protein is an ascorbate transporter at the chloroplast envelope membrane, which may be required for tolerance to strong light stress.
Published Date
2015-01-05
Publication Title
Nature Communications
Volume
volume6
Publisher
Nature Publishing Group
ISSN
2041-1723
Content Type
Journal Article
Official Url
http://dx.doi.org/10.1038/ncomms6928
language
英語
Copyright Holders
© 2015 Macmillan Publishers Limited. All rights reserved. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
File Version
publisher
Refereed
True
DOI
PubMed ID
Web of Science KeyUT