The expression of BrMDHAR gene in chloroplasts and mitochondria enhances tolerance to freezing stress in Arabidopsis thaliana

Autor: S. Y. Shin, Y. S. Kim, I. S. Kim, Y. H. Kim, H. M. Park, H. S. Yoon
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Biologia Plantarum, Vol 58, Iss 3, Pp 456-468 (2014)
Druh dokumentu: article
ISSN: 1573-8264
DOI: 10.1007/s10535-014-0416-7
Popis: In chloroplasts and mitochondria, antioxidant mechanisms include the ascorbate-glutathione cycle, and monodehydroascorbate reductase (MDHAR) is important for regeneration of ascorbate (AsA) from monodehydroascorbate (MDHA). To improve detoxification of reactive oxygen species (ROS), we established a construct of the MDHAR gene from Brassica rapa fused to the targeting signal peptides of Pisum sativum glutathione reductase (GR), which was controlled by a stress-inducible SWPA2 promoter, and introduced this expression system into Arabidopsis thaliana. Transgenic (TG) plants overexpressing BrMDHAR targeted to chloroplasts and mitochondria through signal peptides showed an elevated MDHAR activity and an increased ratio of AsA to dehydroascorbate (DHA) when compared to wild-type (WT) plants under a freezing stress. These led to increased photosynthetic parameters, redox homeostasis, and biomass in TG plants when compared to the WT plants. Our results suggest that the overexpression of the BrMDHAR gene targeted to chloroplasts and mitochondria conferred an enhanced tolerance against the freezing stress, and a stress adaptation of dual-targeted BrMDHAR was better than that of single BrMDHAR.
Databáze: Directory of Open Access Journals