Plant homologs of the Plasmodium falciparum chloroquine-resistance transporter, PfCRT, are required for glutathione homeostasis and stress responses
In Arabidopsis thaliana, biosynthesis of the essential thiol antioxidant, glutathione (GSH), is plastid-regulated, but many GSH functions, including heavy metal detoxification and plant defense activation, depend on cytosolic GSH. This finding suggests that plastid and cytosol thiol pools are closel...
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| Main Authors: | , , , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
February 2, 2010
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| In: |
Proceedings of the National Academy of Sciences of the United States of America
Year: 2010, Volume: 107, Issue: 5, Pages: 2331-2336 |
| ISSN: | 1091-6490 |
| DOI: | 10.1073/pnas.0913689107 |
| Online Access: | Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1073/pnas.0913689107 Verlag, kostenfrei, Volltext: http://www.pnas.org/content/107/5/2331 
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| Author Notes: | Spencer C. Maughan, Maciej Pasternak, Narelle Cairns, Guy Kiddle, Thorsten Brach, Renee Jarvis, Florian Haas, Jeroen Nieuwland, Benson Lim, Christopher Müller, Enrique Salcedo-Sora, Cordula Kruse, Mathilde Orsel, Rüdiger Hell, Anthony J. Miller, Patrick Bray, Christine H. Foyer, James A. H. Murray, Andreas J. Meyer, and Christopher S. Cobbett |
| Summary: | In Arabidopsis thaliana, biosynthesis of the essential thiol antioxidant, glutathione (GSH), is plastid-regulated, but many GSH functions, including heavy metal detoxification and plant defense activation, depend on cytosolic GSH. This finding suggests that plastid and cytosol thiol pools are closely integrated and we show that in Arabidopsis this integration requires a family of three plastid thiol transporters homologous to the Plasmodium falciparum chloroquine-resistance transporter, PfCRT. Arabidopsis mutants lacking these transporters are heavy metal-sensitive, GSH-deficient, and hypersensitive to Phytophthora infection, confirming a direct requirement for correct GSH homeostasis in defense responses. Compartment-specific measurements of the glutathione redox potential using redox-sensitive GFP showed that knockout of the entire transporter family resulted in a more oxidized glutathione redox potential in the cytosol, but not in the plastids, indicating the GSH-deficient phenotype is restricted to the cytosolic compartment. Expression of the transporters in Xenopus oocytes confirmed that each can mediate GSH uptake. We conclude that these transporters play a significant role in regulating GSH levels and the redox potential of the cytosol. |
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| Item Description: | Gesehen am 30.05.2017 |
| Physical Description: | Online Resource |
| ISSN: | 1091-6490 |
| DOI: | 10.1073/pnas.0913689107 |